[SDC-28] JTOSCA initial commit

Change-Id: Ic0ede56c1cc513e632c36954a4227317ae357020
Signed-off-by: Pavel Aharoni <pa0916@att.com>

76 files changed, 19271 insertions, 0 deletions

diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/Capability.java b/src/main/java/org/openecomp/sdc/toscaparser/api/Capability.java
new file mode 100644
index 0000000..09571db
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/Capability.java
@@ -0,0 +1,121 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.elements.CapabilityTypeDef;
+import org.openecomp.sdc.toscaparser.api.elements.PropertyDef;
+
+public class Capability {
+	
+	private String name;
+	private LinkedHashMap<String,Object> _properties;
+	private CapabilityTypeDef _definition;
+
+	public Capability(String cname, 
+				 	  LinkedHashMap<String,Object> cproperties,
+				 	 CapabilityTypeDef cdefinition) {
+		name = cname;
+		_properties = cproperties;
+		_definition = cdefinition;
+	}
+	
+	public ArrayList<Property> getPropertiesObjects() {
+		// Return a list of property objects
+		ArrayList<Property> properties = new ArrayList<Property>();
+		LinkedHashMap<String,Object> props = _properties;
+		if(props != null) {
+			for(Map.Entry<String,Object> me: props.entrySet()) {
+				String pname = me.getKey();
+				Object pvalue = me.getValue();
+				
+				LinkedHashMap<String,PropertyDef> propsDef = _definition.getPropertiesDef();
+				if(propsDef != null) {
+					PropertyDef pd = (PropertyDef)propsDef.get(pname);
+					if(pd != null) {
+						properties.add(new Property(pname,pvalue,pd.getSchema(),null));
+					}
+				}
+			}
+		}
+		return properties;
+	}
+	
+	public LinkedHashMap<String,Property> getProperties() {
+        // Return a dictionary of property name-object pairs
+		LinkedHashMap<String,Property> npps = new LinkedHashMap<>();
+		for(Property p: getPropertiesObjects()) {
+			npps.put(p.getName(),p);
+		}
+		return npps;
+	}
+
+	public Object getPropertyValue(String pname) {
+        // Return the value of a given property name
+		LinkedHashMap<String,Property> props = getProperties();
+        if(props != null && props.get(pname) != null) {
+            return props.get(name).getValue();
+        }
+        return null;
+	}
+
+	 public String getName() {
+		 return name;
+	 }
+	 
+	 public CapabilityTypeDef getDefinition() {
+		 return _definition;
+	 }
+	 
+	 // setter
+	 public void setProperty(String pname,Object pvalue) {
+		 _properties.put(pname,pvalue);
+	 }
+
+    @Override
+    public String toString() {
+        return "Capability{" +
+                "name='" + name + '\'' +
+                ", _properties=" + _properties +
+                ", _definition=" + _definition +
+                '}';
+    }
+}
+
+/*python
+
+from toscaparser.properties import Property
+
+
+class Capability(object):
+    '''TOSCA built-in capabilities type.'''
+
+    def __init__(self, name, properties, definition):
+        self.name = name
+        self._properties = properties
+        self.definition = definition
+
+    def get_properties_objects(self):
+        '''Return a list of property objects.'''
+        properties = []
+        props = self._properties
+        if props:
+            for name, value in props.items():
+                props_def = self.definition.get_properties_def()
+                if props_def and name in props_def:
+                    properties.append(Property(name, value,
+                                               props_def[name].schema))
+        return properties
+
+    def get_properties(self):
+        '''Return a dictionary of property name-object pairs.'''
+        return {prop.name: prop
+                for prop in self.get_properties_objects()}
+
+    def get_property_value(self, name):
+        '''Return the value of a given property name.'''
+        props = self.get_properties()
+        if props and name in props:
+            return props[name].value
+*/ 
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/DataEntity.java b/src/main/java/org/openecomp/sdc/toscaparser/api/DataEntity.java
new file mode 100644
index 0000000..350068b
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/DataEntity.java
@@ -0,0 +1,450 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedHashMap;
+import java.util.List;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.*;
+import org.openecomp.sdc.toscaparser.api.elements.constraints.Constraint;
+import org.openecomp.sdc.toscaparser.api.elements.constraints.Schema;
+import org.openecomp.sdc.toscaparser.api.functions.Function;
+import org.openecomp.sdc.toscaparser.api.utils.TOSCAVersionProperty;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.openecomp.sdc.toscaparser.api.utils.ValidateUtils;
+
+public class DataEntity {
+    // A complex data value entity
+	
+	private LinkedHashMap<String,Object> customDef;
+	private DataType dataType;
+	private LinkedHashMap<String,PropertyDef> schema;
+	private Object value;
+	private String propertyName;
+	
+	public DataEntity(String _dataTypeName,Object _valueDict,
+					  LinkedHashMap<String,Object> _customDef,String _propName) {
+		
+        customDef = _customDef;
+        dataType = new DataType(_dataTypeName,_customDef);
+        schema = dataType.getAllProperties();
+        value = _valueDict;
+        propertyName = _propName;
+	}
+	
+	@SuppressWarnings("unchecked")
+	public Object validate() {
+		// Validate the value by the definition of the datatype
+
+        // A datatype can not have both 'type' and 'properties' definitions.
+        // If the datatype has 'type' definition
+        if(dataType.getValueType() != null) {
+            value = DataEntity.validateDatatype(dataType.getValueType(),value,null,customDef,null);
+            Schema schemaCls = new Schema(propertyName,dataType.getDefs());
+            for(Constraint constraint: schemaCls.getConstraints()) {
+                constraint.validate(value);
+            }
+        }
+        // If the datatype has 'properties' definition
+        else {
+            if(!(value instanceof LinkedHashMap)) {
+            	//ERROR under investigation
+                ThreadLocalsHolder.getCollector().appendWarning(String.format(
+                    "TypeMismatchError: \"%s\" is not a map. The type is \"%s\"",
+                    value.toString(),dataType.getType()));
+                
+				if (value instanceof List && ((List) value).size() > 0)  {
+					value = ((List) value).get(0);
+				}
+
+				if (!(value instanceof LinkedHashMap))  {
+					return value;
+				}
+			}
+
+
+
+			LinkedHashMap<String,Object> valueDict = (LinkedHashMap<String,Object>)value;
+            ArrayList<String> allowedProps = new ArrayList<>();
+            ArrayList<String> requiredProps = new ArrayList<>();
+            LinkedHashMap<String,Object> defaultProps = new LinkedHashMap<>();
+            if(schema != null) {
+            	allowedProps.addAll(schema.keySet());
+            	for(String name: schema.keySet()) {
+            		PropertyDef propDef = schema.get(name);
+            		if(propDef.isRequired()) {
+            			requiredProps.add(name);
+            		}
+            		if(propDef.getDefault() != null) {
+            			defaultProps.put(name,propDef.getDefault());
+            		}
+            	}
+            }
+            
+            // check allowed field
+            for(String valueKey: valueDict.keySet()) {
+            	//1710 devlop JSON validation
+            	if(!("json").equals(dataType.getType()) && !allowedProps.contains(valueKey)) {
+                    ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "UnknownFieldError: Data value of type \"%s\" contains unknown field \"%s\"",
+                        dataType.getType(),valueKey));
+            	}
+            }
+
+            // check default field
+            for(String defKey: defaultProps.keySet()) {
+            	Object defValue = defaultProps.get(defKey);
+            	if(valueDict.get(defKey) == null) {
+            		valueDict.put(defKey, defValue);            		
+            	}
+            	
+            }
+            
+            // check missing field
+            ArrayList<String> missingProp = new ArrayList<>();
+            for(String reqKey: requiredProps) {
+                if(!valueDict.keySet().contains(reqKey)) {
+                    missingProp.add(reqKey);
+                }
+            }
+            if(missingProp.size() > 0) {
+                ThreadLocalsHolder.getCollector().appendWarning(String.format(
+                    "MissingRequiredFieldError: Data value of type \"%s\" is missing required field(s) \"%s\"",
+                    dataType.getType(),missingProp.toString()));
+            }
+            
+            // check every field
+            for(String vname: valueDict.keySet()) {
+            	Object vvalue = valueDict.get(vname);
+            	LinkedHashMap<String,Object> schemaName = _findSchema(vname);
+            	if(schemaName == null) {
+            		continue;
+            	}
+            	Schema propSchema = new Schema(vname,schemaName);
+                // check if field value meets type defined
+                DataEntity.validateDatatype(propSchema.getType(), 
+                							vvalue,
+                                            propSchema.getEntrySchema(),
+                                            customDef,
+                                            null);
+            	
+                // check if field value meets constraints defined
+                if(propSchema.getConstraints() != null) {
+                    for(Constraint constraint: propSchema.getConstraints()) {
+                        if(vvalue instanceof ArrayList) {
+                            for(Object val: (ArrayList<Object>)vvalue) {
+                                constraint.validate(val);
+                            }
+                        }
+                        else {
+                            constraint.validate(vvalue);
+                        }
+                    }
+                }
+            }
+        }
+        return value;
+	}
+
+	private LinkedHashMap<String,Object> _findSchema(String name) {
+		if(schema != null && schema.get(name) != null) {
+			return schema.get(name).getSchema();
+		}
+		return null;
+	}
+	
+	public static Object validateDatatype(String type, 
+										  Object value, 
+										  LinkedHashMap<String,Object> entrySchema, 
+										  LinkedHashMap<String,Object> customDef,
+										  String propName) {
+		// Validate value with given type
+
+        // If type is list or map, validate its entry by entry_schema(if defined)
+        // If type is a user-defined complex datatype, custom_def is required.
+
+		if(Function.isFunction(value)) {
+			return value;
+		}
+		else if (type == null)  {
+			//NOT ANALYZED
+			 ThreadLocalsHolder.getCollector().appendWarning(String.format(
+	                    "MissingType: Type is missing for value \"%s\"",
+	                    value.toString()));
+			 return value;
+		}
+		else if(type.equals(Schema.STRING)) {
+            return ValidateUtils.validateString(value);
+		}
+		else if(type.equals(Schema.INTEGER)) {
+            return ValidateUtils.validateInteger(value);
+		}
+		else if(type.equals(Schema.FLOAT)) {
+            return ValidateUtils.validateFloat(value);
+		}
+		else if(type.equals(Schema.NUMBER)) {
+            return ValidateUtils.validateNumeric(value);
+		}
+		else if(type.equals(Schema.BOOLEAN)) {
+            return ValidateUtils.validateBoolean(value);
+		}
+		else if(type.equals(Schema.RANGE)) {
+            return ValidateUtils.validateRange(value);
+		}
+		else if(type.equals(Schema.TIMESTAMP)) {
+            ValidateUtils.validateTimestamp(value);
+            return value;
+		}
+		else if(type.equals(Schema.LIST)) {
+            ValidateUtils.validateList(value);
+            if(entrySchema != null) {
+            	DataEntity.validateEntry(value,entrySchema,customDef);
+            }
+            return value;
+		}
+		else if(type.equals(Schema.SCALAR_UNIT_SIZE)) {
+            return (new ScalarUnitSize(value)).validateScalarUnit();
+		}
+		else if(type.equals(Schema.SCALAR_UNIT_FREQUENCY)) {
+            return (new ScalarUnitFrequency(value)).validateScalarUnit();
+		}
+		else if(type.equals(Schema.SCALAR_UNIT_TIME)) {
+            return (new ScalarUnitTime(value)).validateScalarUnit();
+		}
+		else if(type.equals(Schema.VERSION)) {
+            return (new TOSCAVersionProperty(value)).getVersion();
+		}
+		else if(type.equals(Schema.MAP)) {
+            ValidateUtils.validateMap(value);
+            if(entrySchema != null) {
+            	DataEntity.validateEntry(value,entrySchema,customDef);
+            }
+            return value;
+		}
+		else if(type.equals(Schema.PORTSPEC)) {
+            // tODO(TBD) bug 1567063, validate source & target as PortDef type
+            // as complex types not just as integers
+            PortSpec.validateAdditionalReq(value,propName,customDef);
+		}
+        else {
+            DataEntity data = new DataEntity(type,value,customDef,null);
+            return data.validate();
+        }
+        
+		return value;
+	}
+	
+	@SuppressWarnings("unchecked")
+	public static Object validateEntry(Object value,
+			  						   LinkedHashMap<String,Object> entrySchema,
+									   LinkedHashMap<String,Object> customDef) {
+		
+        // Validate entries for map and list
+        Schema schema = new Schema(null,entrySchema);
+        Object valueob = value;
+        ArrayList<Object> valueList = null;
+        if(valueob  instanceof LinkedHashMap) {
+            valueList = new ArrayList<Object>(((LinkedHashMap<String,Object>)valueob).values());
+        }
+        else if(valueob instanceof ArrayList) {
+        	valueList = (ArrayList<Object>)valueob;
+        }
+        if(valueList != null) {
+	        for(Object v: valueList) {
+	            DataEntity.validateDatatype(schema.getType(),v,schema.getEntrySchema(),customDef,null);
+	            if(schema.getConstraints() !=  null) {
+	                for(Constraint constraint: schema.getConstraints()) {
+	                    constraint.validate(v);
+	                }
+	            }
+	        }
+        }
+		return value;
+	}
+
+	@Override
+	public String toString() {
+		return "DataEntity{" +
+				"customDef=" + customDef +
+				", dataType=" + dataType +
+				", schema=" + schema +
+				", value=" + value +
+				", propertyName='" + propertyName + '\'' +
+				'}';
+	}
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import MissingRequiredFieldError
+from toscaparser.common.exception import TypeMismatchError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.elements.constraints import Schema
+from toscaparser.elements.datatype import DataType
+from toscaparser.elements.portspectype import PortSpec
+from toscaparser.elements.scalarunit import ScalarUnit_Frequency
+from toscaparser.elements.scalarunit import ScalarUnit_Size
+from toscaparser.elements.scalarunit import ScalarUnit_Time
+from toscaparser.utils.gettextutils import _
+from toscaparser.utils import validateutils
+
+
+class DataEntity(object):
+    '''A complex data value entity.'''
+
+    def __init__(self, datatypename, value_dict, custom_def=None,
+                 prop_name=None):
+        self.custom_def = custom_def
+        self.datatype = DataType(datatypename, custom_def)
+        self.schema = self.datatype.get_all_properties()
+        self.value = value_dict
+        self.property_name = prop_name
+
+    def validate(self):
+        '''Validate the value by the definition of the datatype.'''
+
+        # A datatype can not have both 'type' and 'properties' definitions.
+        # If the datatype has 'type' definition
+        if self.datatype.value_type:
+            self.value = DataEntity.validate_datatype(self.datatype.value_type,
+                                                      self.value,
+                                                      None,
+                                                      self.custom_def)
+            schema = Schema(self.property_name, self.datatype.defs)
+            for constraint in schema.constraints:
+                constraint.validate(self.value)
+        # If the datatype has 'properties' definition
+        else:
+            if not isinstance(self.value, dict):
+                ExceptionCollector.appendException(
+                    TypeMismatchError(what=self.value,
+                                      type=self.datatype.type))
+            allowed_props = []
+            required_props = []
+            default_props = {}
+            if self.schema:
+                allowed_props = self.schema.keys()
+                for name, prop_def in self.schema.items():
+                    if prop_def.required:
+                        required_props.append(name)
+                    if prop_def.default:
+                        default_props[name] = prop_def.default
+
+            # check allowed field
+            for value_key in list(self.value.keys()):
+                if value_key not in allowed_props:
+                    ExceptionCollector.appendException(
+                        UnknownFieldError(what=(_('Data value of type "%s"')
+                                                % self.datatype.type),
+                                          field=value_key))
+
+            # check default field
+            for def_key, def_value in list(default_props.items()):
+                if def_key not in list(self.value.keys()):
+                    self.value[def_key] = def_value
+
+            # check missing field
+            missingprop = []
+            for req_key in required_props:
+                if req_key not in list(self.value.keys()):
+                    missingprop.append(req_key)
+            if missingprop:
+                ExceptionCollector.appendException(
+                    MissingRequiredFieldError(
+                        what=(_('Data value of type "%s"')
+                              % self.datatype.type), required=missingprop))
+
+            # check every field
+            for name, value in list(self.value.items()):
+                schema_name = self._find_schema(name)
+                if not schema_name:
+                    continue
+                prop_schema = Schema(name, schema_name)
+                # check if field value meets type defined
+                DataEntity.validate_datatype(prop_schema.type, value,
+                                             prop_schema.entry_schema,
+                                             self.custom_def)
+                # check if field value meets constraints defined
+                if prop_schema.constraints:
+                    for constraint in prop_schema.constraints:
+                        if isinstance(value, list):
+                            for val in value:
+                                constraint.validate(val)
+                        else:
+                            constraint.validate(value)
+
+        return self.value
+
+    def _find_schema(self, name):
+        if self.schema and name in self.schema.keys():
+            return self.schema[name].schema
+
+    @staticmethod
+    def validate_datatype(type, value, entry_schema=None, custom_def=None,
+                          prop_name=None):
+        '''Validate value with given type.
+
+        If type is list or map, validate its entry by entry_schema(if defined)
+        If type is a user-defined complex datatype, custom_def is required.
+        '''
+        from toscaparser.functions import is_function
+        if is_function(value):
+            return value
+        if type == Schema.STRING:
+            return validateutils.validate_string(value)
+        elif type == Schema.INTEGER:
+            return validateutils.validate_integer(value)
+        elif type == Schema.FLOAT:
+            return validateutils.validate_float(value)
+        elif type == Schema.NUMBER:
+            return validateutils.validate_numeric(value)
+        elif type == Schema.BOOLEAN:
+            return validateutils.validate_boolean(value)
+        elif type == Schema.RANGE:
+            return validateutils.validate_range(value)
+        elif type == Schema.TIMESTAMP:
+            validateutils.validate_timestamp(value)
+            return value
+        elif type == Schema.LIST:
+            validateutils.validate_list(value)
+            if entry_schema:
+                DataEntity.validate_entry(value, entry_schema, custom_def)
+            return value
+        elif type == Schema.SCALAR_UNIT_SIZE:
+            return ScalarUnit_Size(value).validate_scalar_unit()
+        elif type == Schema.SCALAR_UNIT_FREQUENCY:
+            return ScalarUnit_Frequency(value).validate_scalar_unit()
+        elif type == Schema.SCALAR_UNIT_TIME:
+            return ScalarUnit_Time(value).validate_scalar_unit()
+        elif type == Schema.VERSION:
+            return validateutils.TOSCAVersionProperty(value).get_version()
+        elif type == Schema.MAP:
+            validateutils.validate_map(value)
+            if entry_schema:
+                DataEntity.validate_entry(value, entry_schema, custom_def)
+            return value
+        elif type == Schema.PORTSPEC:
+            # tODO(TBD) bug 1567063, validate source & target as PortDef type
+            # as complex types not just as integers
+            PortSpec.validate_additional_req(value, prop_name, custom_def)
+        else:
+            data = DataEntity(type, value, custom_def)
+            return data.validate()
+
+    @staticmethod
+    def validate_entry(value, entry_schema, custom_def=None):
+        '''Validate entries for map and list.'''
+        schema = Schema(None, entry_schema)
+        valuelist = value
+        if isinstance(value, dict):
+            valuelist = list(value.values())
+        for v in valuelist:
+            DataEntity.validate_datatype(schema.type, v, schema.entry_schema,
+                                         custom_def)
+            if schema.constraints:
+                for constraint in schema.constraints:
+                    constraint.validate(v)
+        return value
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/DataEntity.java.orig b/src/main/java/org/openecomp/sdc/toscaparser/api/DataEntity.java.orig
new file mode 100644
index 0000000..c3f8fb5
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/DataEntity.java.orig
@@ -0,0 +1,453 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedHashMap;
+import java.util.List;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.*;
+import org.openecomp.sdc.toscaparser.api.elements.constraints.Constraint;
+import org.openecomp.sdc.toscaparser.api.elements.constraints.Schema;
+import org.openecomp.sdc.toscaparser.api.functions.Function;
+import org.openecomp.sdc.toscaparser.api.utils.TOSCAVersionProperty;
+import org.openecomp.sdc.toscaparser.api.utils.ValidateUtils;
+
+public class DataEntity {
+    // A complex data value entity
+	
+	private LinkedHashMap<String,Object> customDef;
+	private DataType dataType;
+	private LinkedHashMap<String,PropertyDef> schema;
+	private Object value;
+	private String propertyName;
+	
+	public DataEntity(String _dataTypeName,Object _valueDict,
+					  LinkedHashMap<String,Object> _customDef,String _propName) {
+		
+        customDef = _customDef;
+        dataType = new DataType(_dataTypeName,_customDef);
+        schema = dataType.getAllProperties();
+        value = _valueDict;
+        propertyName = _propName;
+	}
+	
+	@SuppressWarnings("unchecked")
+	public Object validate() {
+		// Validate the value by the definition of the datatype
+
+        // A datatype can not have both 'type' and 'properties' definitions.
+        // If the datatype has 'type' definition
+        if(dataType.getValueType() != null) {
+            value = DataEntity.validateDatatype(dataType.getValueType(),value,null,customDef,null);
+            Schema schemaCls = new Schema(propertyName,dataType.getDefs());
+            for(Constraint constraint: schemaCls.getConstraints()) {
+                constraint.validate(value);
+            }
+        }
+        // If the datatype has 'properties' definition
+        else {
+            if(!(value instanceof LinkedHashMap)) {
+            	//ERROR under investigation
+                ExceptionCollector.appendWarning(String.format(
+                    "TypeMismatchError: \"%s\" is not a map. The type is \"%s\"",
+                    value.toString(),dataType.getType()));
+<<<<<<< HEAD
+                return value;
+            }
+            LinkedHashMap<String,Object> valueDict = (LinkedHashMap<String,Object>)value;
+=======
+
+				if (value instanceof List)
+					value = ((List) value).get(0);
+
+				if (!(value instanceof LinkedHashMap))
+					return value;
+			}
+
+
+
+			LinkedHashMap<String,Object> valueDict = (LinkedHashMap<String,Object>)value;
+>>>>>>> master
+            ArrayList<String> allowedProps = new ArrayList<>();
+            ArrayList<String> requiredProps = new ArrayList<>();
+            LinkedHashMap<String,Object> defaultProps = new LinkedHashMap<>();
+            if(schema != null) {
+            	allowedProps.addAll(schema.keySet());
+            	for(String name: schema.keySet()) {
+            		PropertyDef propDef = schema.get(name);
+            		if(propDef.isRequired()) {
+            			requiredProps.add(name);
+            		}
+            		if(propDef.getDefault() != null) {
+            			defaultProps.put(name,propDef.getDefault());
+            		}
+            	}
+            }
+            
+            // check allowed field
+            for(String valueKey: valueDict.keySet()) {
+            	//1710 devlop JSON validation
+            	if(!("json").equals(dataType.getType()) && !allowedProps.contains(valueKey)) {
+                    ExceptionCollector.appendException(String.format(
+                        "UnknownFieldError: Data value of type \"%s\" contains unknown field \"%s\"",
+                        dataType.getType(),valueKey));
+            	}
+            }
+
+            // check default field
+            for(String defKey: defaultProps.keySet()) {
+            	Object defValue = defaultProps.get(defKey);
+            	if(valueDict.get(defKey) == null) {
+            		valueDict.put(defKey, defValue);            		
+            	}
+            	
+            }
+            
+            // check missing field
+            ArrayList<String> missingProp = new ArrayList<>();
+            for(String reqKey: requiredProps) {
+                if(!valueDict.keySet().contains(reqKey)) {
+                    missingProp.add(reqKey);
+                }
+            }
+            if(missingProp.size() > 0) {
+                ExceptionCollector.appendWarning(String.format(
+                    "MissingRequiredFieldError: Data value of type \"%s\" is missing required field(s) \"%s\"",
+                    dataType.getType(),missingProp.toString()));
+            }
+            
+            // check every field
+            for(String vname: valueDict.keySet()) {
+            	Object vvalue = valueDict.get(vname);
+            	LinkedHashMap<String,Object> schemaName = _findSchema(vname);
+            	if(schemaName == null) {
+            		continue;
+            	}
+            	Schema propSchema = new Schema(vname,schemaName);
+                // check if field value meets type defined
+                DataEntity.validateDatatype(propSchema.getType(), 
+                							vvalue,
+                                            propSchema.getEntrySchema(),
+                                            customDef,
+                                            null);
+            	
+                // check if field value meets constraints defined
+                if(propSchema.getConstraints() != null) {
+                    for(Constraint constraint: propSchema.getConstraints()) {
+                        if(vvalue instanceof ArrayList) {
+                            for(Object val: (ArrayList<Object>)vvalue) {
+                                constraint.validate(val);
+                            }
+                        }
+                        else {
+                            constraint.validate(vvalue);
+                        }
+                    }
+                }
+            }
+        }
+        return value;
+	}
+
+	private LinkedHashMap<String,Object> _findSchema(String name) {
+		if(schema != null && schema.get(name) != null) {
+			return schema.get(name).getSchema();
+		}
+		return null;
+	}
+	
+	public static Object validateDatatype(String type, 
+										  Object value, 
+										  LinkedHashMap<String,Object> entrySchema, 
+										  LinkedHashMap<String,Object> customDef,
+										  String propName) {
+		// Validate value with given type
+
+        // If type is list or map, validate its entry by entry_schema(if defined)
+        // If type is a user-defined complex datatype, custom_def is required.
+
+		if(Function.isFunction(value)) {
+			return value;
+		}
+		else if (type == null)  {
+			//NOT ANALYZED
+			 ExceptionCollector.appendWarning(String.format(
+	                    "MissingType: Type is missing for value \"%s\"",
+	                    value.toString()));
+			 return value;
+		}
+		else if(type.equals(Schema.STRING)) {
+            return ValidateUtils.validateString(value);
+		}
+		else if(type.equals(Schema.INTEGER)) {
+            return ValidateUtils.validateInteger(value);
+		}
+		else if(type.equals(Schema.FLOAT)) {
+            return ValidateUtils.validateFloat(value);
+		}
+		else if(type.equals(Schema.NUMBER)) {
+            return ValidateUtils.validateNumeric(value);
+		}
+		else if(type.equals(Schema.BOOLEAN)) {
+            return ValidateUtils.validateBoolean(value);
+		}
+		else if(type.equals(Schema.RANGE)) {
+            return ValidateUtils.validateRange(value);
+		}
+		else if(type.equals(Schema.TIMESTAMP)) {
+            ValidateUtils.validateTimestamp(value);
+            return value;
+		}
+		else if(type.equals(Schema.LIST)) {
+            ValidateUtils.validateList(value);
+            if(entrySchema != null) {
+            	DataEntity.validateEntry(value,entrySchema,customDef);
+            }
+            return value;
+		}
+		else if(type.equals(Schema.SCALAR_UNIT_SIZE)) {
+            return (new ScalarUnitSize(value)).validateScalarUnit();
+		}
+		else if(type.equals(Schema.SCALAR_UNIT_FREQUENCY)) {
+            return (new ScalarUnitFrequency(value)).validateScalarUnit();
+		}
+		else if(type.equals(Schema.SCALAR_UNIT_TIME)) {
+            return (new ScalarUnitTime(value)).validateScalarUnit();
+		}
+		else if(type.equals(Schema.VERSION)) {
+            return (new TOSCAVersionProperty(value)).getVersion();
+		}
+		else if(type.equals(Schema.MAP)) {
+            ValidateUtils.validateMap(value);
+            if(entrySchema != null) {
+            	DataEntity.validateEntry(value,entrySchema,customDef);
+            }
+            return value;
+		}
+		else if(type.equals(Schema.PORTSPEC)) {
+            // tODO(TBD) bug 1567063, validate source & target as PortDef type
+            // as complex types not just as integers
+            PortSpec.validateAdditionalReq(value,propName,customDef);
+		}
+        else {
+            DataEntity data = new DataEntity(type,value,customDef,null);
+            return data.validate();
+        }
+        
+		return value;
+	}
+	
+	@SuppressWarnings("unchecked")
+	public static Object validateEntry(Object value,
+			  						   LinkedHashMap<String,Object> entrySchema,
+									   LinkedHashMap<String,Object> customDef) {
+		
+        // Validate entries for map and list
+        Schema schema = new Schema(null,entrySchema);
+        Object valueob = value;
+        ArrayList<Object> valueList = null;
+        if(valueob  instanceof LinkedHashMap) {
+            valueList = new ArrayList<Object>(((LinkedHashMap<String,Object>)valueob).values());
+        }
+        else if(valueob instanceof ArrayList) {
+        	valueList = (ArrayList<Object>)valueob;
+        }
+        if(valueList != null) {
+	        for(Object v: valueList) {
+	            DataEntity.validateDatatype(schema.getType(),v,schema.getEntrySchema(),customDef,null);
+	            if(schema.getConstraints() !=  null) {
+	                for(Constraint constraint: schema.getConstraints()) {
+	                    constraint.validate(v);
+	                }
+	            }
+	        }
+        }
+		return value;
+	}
+
+	@Override
+	public String toString() {
+		return "DataEntity{" +
+				"customDef=" + customDef +
+				", dataType=" + dataType +
+				", schema=" + schema +
+				", value=" + value +
+				", propertyName='" + propertyName + '\'' +
+				'}';
+	}
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import MissingRequiredFieldError
+from toscaparser.common.exception import TypeMismatchError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.elements.constraints import Schema
+from toscaparser.elements.datatype import DataType
+from toscaparser.elements.portspectype import PortSpec
+from toscaparser.elements.scalarunit import ScalarUnit_Frequency
+from toscaparser.elements.scalarunit import ScalarUnit_Size
+from toscaparser.elements.scalarunit import ScalarUnit_Time
+from toscaparser.utils.gettextutils import _
+from toscaparser.utils import validateutils
+
+
+class DataEntity(object):
+    '''A complex data value entity.'''
+
+    def __init__(self, datatypename, value_dict, custom_def=None,
+                 prop_name=None):
+        self.custom_def = custom_def
+        self.datatype = DataType(datatypename, custom_def)
+        self.schema = self.datatype.get_all_properties()
+        self.value = value_dict
+        self.property_name = prop_name
+
+    def validate(self):
+        '''Validate the value by the definition of the datatype.'''
+
+        # A datatype can not have both 'type' and 'properties' definitions.
+        # If the datatype has 'type' definition
+        if self.datatype.value_type:
+            self.value = DataEntity.validate_datatype(self.datatype.value_type,
+                                                      self.value,
+                                                      None,
+                                                      self.custom_def)
+            schema = Schema(self.property_name, self.datatype.defs)
+            for constraint in schema.constraints:
+                constraint.validate(self.value)
+        # If the datatype has 'properties' definition
+        else:
+            if not isinstance(self.value, dict):
+                ExceptionCollector.appendException(
+                    TypeMismatchError(what=self.value,
+                                      type=self.datatype.type))
+            allowed_props = []
+            required_props = []
+            default_props = {}
+            if self.schema:
+                allowed_props = self.schema.keys()
+                for name, prop_def in self.schema.items():
+                    if prop_def.required:
+                        required_props.append(name)
+                    if prop_def.default:
+                        default_props[name] = prop_def.default
+
+            # check allowed field
+            for value_key in list(self.value.keys()):
+                if value_key not in allowed_props:
+                    ExceptionCollector.appendException(
+                        UnknownFieldError(what=(_('Data value of type "%s"')
+                                                % self.datatype.type),
+                                          field=value_key))
+
+            # check default field
+            for def_key, def_value in list(default_props.items()):
+                if def_key not in list(self.value.keys()):
+                    self.value[def_key] = def_value
+
+            # check missing field
+            missingprop = []
+            for req_key in required_props:
+                if req_key not in list(self.value.keys()):
+                    missingprop.append(req_key)
+            if missingprop:
+                ExceptionCollector.appendException(
+                    MissingRequiredFieldError(
+                        what=(_('Data value of type "%s"')
+                              % self.datatype.type), required=missingprop))
+
+            # check every field
+            for name, value in list(self.value.items()):
+                schema_name = self._find_schema(name)
+                if not schema_name:
+                    continue
+                prop_schema = Schema(name, schema_name)
+                # check if field value meets type defined
+                DataEntity.validate_datatype(prop_schema.type, value,
+                                             prop_schema.entry_schema,
+                                             self.custom_def)
+                # check if field value meets constraints defined
+                if prop_schema.constraints:
+                    for constraint in prop_schema.constraints:
+                        if isinstance(value, list):
+                            for val in value:
+                                constraint.validate(val)
+                        else:
+                            constraint.validate(value)
+
+        return self.value
+
+    def _find_schema(self, name):
+        if self.schema and name in self.schema.keys():
+            return self.schema[name].schema
+
+    @staticmethod
+    def validate_datatype(type, value, entry_schema=None, custom_def=None,
+                          prop_name=None):
+        '''Validate value with given type.
+
+        If type is list or map, validate its entry by entry_schema(if defined)
+        If type is a user-defined complex datatype, custom_def is required.
+        '''
+        from toscaparser.functions import is_function
+        if is_function(value):
+            return value
+        if type == Schema.STRING:
+            return validateutils.validate_string(value)
+        elif type == Schema.INTEGER:
+            return validateutils.validate_integer(value)
+        elif type == Schema.FLOAT:
+            return validateutils.validate_float(value)
+        elif type == Schema.NUMBER:
+            return validateutils.validate_numeric(value)
+        elif type == Schema.BOOLEAN:
+            return validateutils.validate_boolean(value)
+        elif type == Schema.RANGE:
+            return validateutils.validate_range(value)
+        elif type == Schema.TIMESTAMP:
+            validateutils.validate_timestamp(value)
+            return value
+        elif type == Schema.LIST:
+            validateutils.validate_list(value)
+            if entry_schema:
+                DataEntity.validate_entry(value, entry_schema, custom_def)
+            return value
+        elif type == Schema.SCALAR_UNIT_SIZE:
+            return ScalarUnit_Size(value).validate_scalar_unit()
+        elif type == Schema.SCALAR_UNIT_FREQUENCY:
+            return ScalarUnit_Frequency(value).validate_scalar_unit()
+        elif type == Schema.SCALAR_UNIT_TIME:
+            return ScalarUnit_Time(value).validate_scalar_unit()
+        elif type == Schema.VERSION:
+            return validateutils.TOSCAVersionProperty(value).get_version()
+        elif type == Schema.MAP:
+            validateutils.validate_map(value)
+            if entry_schema:
+                DataEntity.validate_entry(value, entry_schema, custom_def)
+            return value
+        elif type == Schema.PORTSPEC:
+            # tODO(TBD) bug 1567063, validate source & target as PortDef type
+            # as complex types not just as integers
+            PortSpec.validate_additional_req(value, prop_name, custom_def)
+        else:
+            data = DataEntity(type, value, custom_def)
+            return data.validate()
+
+    @staticmethod
+    def validate_entry(value, entry_schema, custom_def=None):
+        '''Validate entries for map and list.'''
+        schema = Schema(None, entry_schema)
+        valuelist = value
+        if isinstance(value, dict):
+            valuelist = list(value.values())
+        for v in valuelist:
+            DataEntity.validate_datatype(schema.type, v, schema.entry_schema,
+                                         custom_def)
+            if schema.constraints:
+                for constraint in schema.constraints:
+                    constraint.validate(v)
+        return value
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/EntityTemplate.java b/src/main/java/org/openecomp/sdc/toscaparser/api/EntityTemplate.java
new file mode 100644
index 0000000..e896905
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/EntityTemplate.java
@@ -0,0 +1,832 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.*;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public abstract class EntityTemplate {
+    // Base class for TOSCA templates
+
+	protected static final String DERIVED_FROM = "derived_from";
+	protected static final String PROPERTIES = "properties";
+	protected static final String REQUIREMENTS = "requirements";
+	protected static final String INTERFACES = "interfaces";
+	protected static final String CAPABILITIES = "capabilities";
+	protected static final String TYPE = "type";
+	protected static final String DESCRIPTION = "description";
+	protected static final String DIRECTIVES = "directives";
+	protected static final String ATTRIBUTES = "attributes";
+	protected static final String ARTIFACTS = "artifacts";
+	protected static final String NODE_FILTER = "node_filter";
+	protected static final String COPY = "copy";
+	
+	protected static final String SECTIONS[] = {
+			DERIVED_FROM, PROPERTIES, REQUIREMENTS,INTERFACES, 
+			CAPABILITIES, TYPE, DESCRIPTION, DIRECTIVES,
+			ATTRIBUTES, ARTIFACTS, NODE_FILTER, COPY};
+
+	private static final String NODE = "node";
+	private static final String CAPABILITY = "capability";
+	private static final String RELATIONSHIP = "relationship";
+	private static final String OCCURRENCES = "occurrences";
+	
+	protected static final String REQUIREMENTS_SECTION[] = {
+				NODE, CAPABILITY, RELATIONSHIP, OCCURRENCES, NODE_FILTER};
+    
+	//# Special key names
+	private static final String METADATA = "metadata";
+	protected static final String SPECIAL_SECTIONS[] = {METADATA};
+	
+	protected String name;
+	protected LinkedHashMap<String,Object> entityTpl;
+	protected LinkedHashMap<String,Object> customDef; 
+	protected StatefulEntityType typeDefinition;
+	private ArrayList<Property> _properties;
+	private ArrayList<InterfacesDef> _interfaces; 
+	private ArrayList<Object> _requirements;
+	private ArrayList<Capability> _capabilities;
+
+	// dummy constructor for subclasses that don't want super
+	public EntityTemplate() {
+		return;
+	}
+
+    @SuppressWarnings("unchecked")
+	public EntityTemplate(String _name, 
+    					  LinkedHashMap<String,Object> _template, 
+    					  String _entityName, 
+    					  LinkedHashMap<String,Object> _customDef) {
+        name = _name;
+        entityTpl = _template;
+        customDef = _customDef;
+        _validateField(entityTpl);
+        String type = (String)entityTpl.get("type");
+       	UnsupportedType.validateType(type);
+        if(_entityName.equals("node_type")) {
+        	if(type != null) {
+        		typeDefinition = new NodeType(type, customDef);
+        	}
+        	else {
+        		typeDefinition = null;
+        	}
+        }
+        if(_entityName.equals("relationship_type")) {
+			Object relationship = _template.get("relationship");
+            type = null;
+            if(relationship != null && relationship instanceof LinkedHashMap) {
+                type = (String)((LinkedHashMap<String,Object>)relationship).get("type");
+            }
+            else if(relationship instanceof String) {
+                type = (String)entityTpl.get("relationship");
+            }
+            else {
+                type = (String)entityTpl.get("type");
+            }
+            UnsupportedType.validateType(type);
+            typeDefinition = new RelationshipType(type,null, customDef);
+        }
+        if(_entityName.equals("policy_type")) {
+            if(type == null) {
+                //msg = (_('Policy definition of "%(pname)s" must have'
+                //       ' a "type" ''attribute.') % dict(pname=name))
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"ValidationError: Policy definition of \"%s\" must have a \"type\" attribute",name));
+            }
+            typeDefinition = new PolicyType(type, customDef);
+        }
+        if(_entityName.equals("group_type")) {
+        	if(type != null) {
+        		typeDefinition = new GroupType(type, customDef);
+        	}
+        	else { 
+                typeDefinition = null;
+        	}
+        }
+        _properties = null;
+        _interfaces = null;
+        _requirements = null;
+        _capabilities = null;
+    }
+
+    public String getType() {
+    	if(typeDefinition != null) {
+    		String clType = typeDefinition.getClass().getSimpleName();
+    		if(clType.equals("NodeType")) {
+    			return (String)((NodeType)typeDefinition).getType();
+    		}
+    		else if(clType.equals("PolicyType")) {
+    			return (String)((PolicyType)typeDefinition).getType();
+    		}
+    		else if(clType.equals("GroupType")) {
+    			return (String)((GroupType)typeDefinition).getType();
+    		}
+    		else if(clType.equals("RelationshipType")) {
+    			return (String)((RelationshipType)typeDefinition).getType();
+    		}
+    	}
+    	return null;
+    }
+
+    public Object getParentType() {
+    	if(typeDefinition != null) {
+    		String clType = typeDefinition.getClass().getSimpleName();
+    		if(clType.equals("NodeType")) {
+    			return ((NodeType)typeDefinition).getParentType();
+    		}
+    		else if(clType.equals("PolicyType")) {
+    			return ((PolicyType)typeDefinition).getParentType();
+    		}
+    		else if(clType.equals("GroupType")) {
+    			return ((GroupType)typeDefinition).getParentType();
+    		}
+    		else if(clType.equals("RelationshipType")) {
+    			return ((RelationshipType)typeDefinition).getParentType();
+    		}
+    	}
+    	return null;
+    }
+    
+     @SuppressWarnings("unchecked")
+	public ArrayList<Object> getRequirements() {
+    	if(_requirements == null) {
+    		_requirements = new ArrayList<Object>();
+    		Object ob = ((EntityType)typeDefinition).getValue(REQUIREMENTS,entityTpl,false);
+    		if(ob != null) {
+    			_requirements.addAll((ArrayList<Object>)ob);
+    		}
+    				
+    	}
+    	return _requirements;
+    }
+
+    public ArrayList<Property> getPropertiesObjects() {
+        // Return properties objects for this template
+        if(_properties ==null) {
+            _properties = _createProperties();
+        }
+    	return _properties;
+    }
+    
+    public LinkedHashMap<String,Property> getProperties() {
+    	LinkedHashMap<String,Property> props = new LinkedHashMap<>();
+    	for(Property po: getPropertiesObjects()) {
+    		props.put(((Property)po).getName(),po);
+    	}
+    	return props;
+    }
+    
+    public Object getPropertyValue(String name) {
+    	LinkedHashMap<String,Property> props = getProperties();
+    	Property p = (Property)props.get(name);
+    	return p != null ? p.getValue() : null;
+    }
+
+    public ArrayList<InterfacesDef> getInterfaces() {
+    	if(_interfaces == null) {
+    		_interfaces = _createInterfaces();
+    	}
+    	return _interfaces;
+    }
+    
+    public ArrayList<Capability> getCapabilitiesObjects() {
+        // Return capabilities objects for this template
+    	if(_capabilities == null) {
+    		_capabilities = _createCapabilities();
+    	}
+    	return _capabilities;
+   	
+    }
+    
+    public LinkedHashMap<String,Capability> getCapabilities() {
+    	LinkedHashMap<String,Capability> caps = new LinkedHashMap<String,Capability>();
+    	for(Capability cap: getCapabilitiesObjects()) {
+    		caps.put(cap.getName(),cap);
+    	}
+    	return caps;
+    }
+
+    public boolean isDerivedFrom(String typeStr) {
+    	// Returns true if this object is derived from 'type_str'.
+        // False otherwise
+    	
+    	if(getType() == null) {
+    		return false;
+    	}
+    	else if(getType().equals(typeStr)) {
+    		return true;
+    	}
+    	else if(getParentType() != null) {
+    		return ((EntityType)getParentType()).isDerivedFrom(typeStr);
+    	}
+   		return false;
+    }
+    
+    @SuppressWarnings("unchecked")
+	private ArrayList<Capability> _createCapabilities() {
+    	ArrayList<Capability> capability = new ArrayList<Capability>();
+		LinkedHashMap<String,Object> caps = (LinkedHashMap<String,Object>)
+							((EntityType)typeDefinition).getValue(CAPABILITIES,entityTpl,true);
+		if(caps != null) {
+			//?!? getCapabilities defined only for NodeType...
+			LinkedHashMap<String,CapabilityTypeDef> capabilities = ((NodeType)typeDefinition).getCapabilities();
+			for(Map.Entry<String,Object> me: caps.entrySet()) {
+				String name = me. getKey();
+				LinkedHashMap<String,Object> props = (LinkedHashMap<String,Object>)me.getValue();
+				if(capabilities.get(name) != null) {
+					CapabilityTypeDef c = capabilities.get(name);  // a CapabilityTypeDef
+					LinkedHashMap<String,Object> properties = new LinkedHashMap<String,Object>();
+					// first use the definition default value
+					LinkedHashMap<String,Object> cprops = c.getProperties();
+					if(cprops != null) {
+						for(Map.Entry<String,Object> cpe: cprops.entrySet()) {
+							String propertyName = cpe.getKey();
+							LinkedHashMap<String,Object> propertyDef = (LinkedHashMap<String,Object>)cpe.getValue();
+							Object dob = propertyDef.get("default");
+							if(dob != null) {
+								properties.put(propertyName, dob);
+								
+							}
+						}
+					}
+                    // then update (if available) with the node properties
+					LinkedHashMap<String,Object> pp = (LinkedHashMap<String,Object>)props.get("properties");
+					if(pp != null) {
+						properties.putAll(pp);
+					}
+                    Capability cap = new Capability(name, properties, c);
+                    capability.add(cap);
+				}
+			}
+		}
+		return capability;
+     }
+
+    protected void _validateProperties(LinkedHashMap<String,Object> template,StatefulEntityType entityType) {
+    	@SuppressWarnings("unchecked")
+		LinkedHashMap<String,Object> properties = (LinkedHashMap<String,Object>)entityType.getValue(PROPERTIES,template,false);
+    	_commonValidateProperties(entityType,properties);
+    }
+
+    protected void _validateCapabilities() {
+    	//BUG??? getCapabilities only defined in NodeType...
+    	LinkedHashMap<String,CapabilityTypeDef> typeCapabilities = ((NodeType)typeDefinition).getCapabilities();
+    	ArrayList<String> allowedCaps = new ArrayList<String>();
+    	if(typeCapabilities != null) {
+    		allowedCaps.addAll(typeCapabilities.keySet());
+    	}
+    	@SuppressWarnings("unchecked")
+		LinkedHashMap<String,Object> capabilities = (LinkedHashMap<String,Object>)
+    			((EntityType)typeDefinition).getValue(CAPABILITIES, entityTpl, false);
+    	if(capabilities != null) {
+            _commonValidateField(capabilities, allowedCaps, "capabilities");
+            _validateCapabilitiesProperties(capabilities);
+    	}
+    }
+    
+	@SuppressWarnings("unchecked")
+    private void _validateCapabilitiesProperties(LinkedHashMap<String,Object> capabilities) {
+    	for(Map.Entry<String,Object> me: capabilities.entrySet()) {
+    		String cap = me.getKey();
+			LinkedHashMap<String,Object> props = (LinkedHashMap<String,Object>)me.getValue();
+    		Capability capability = getCapability(cap);
+    		if(capability == null) {
+    			continue;
+    		}
+    		CapabilityTypeDef capabilitydef = capability.getDefinition();
+    		_commonValidateProperties(capabilitydef,(LinkedHashMap<String,Object>)props.get(PROPERTIES));
+    		
+            // validating capability properties values
+    		for(Property prop: getCapability(cap).getPropertiesObjects()) {
+                prop.validate();
+    		               
+                if(cap.equals("scalable") && prop.getName().equals("default_instances")) {
+					LinkedHashMap<String,Object> propDict = (LinkedHashMap<String,Object>)props.get(PROPERTIES);
+                    int minInstances = (int)propDict.get("min_instances");
+                    int maxInstances = (int)propDict.get("max_instances");
+                    int defaultInstances = (int)propDict.get("default_instances");
+                    if(defaultInstances < minInstances || defaultInstances > maxInstances) {
+                        //err_msg = ('"properties" of template "%s": '
+                        //           '"default_instances" value is not between '
+                        //           '"min_instances" and "max_instances".' %
+                        //           self.name)
+                        ThreadLocalsHolder.getCollector().appendException(String.format(
+                            "ValidationError: \"properties\" of template \"%s\": \"default_instances\" value is not between \"min_instances\" and \"max_instances\"",
+                            name));
+                    }
+                }
+    		}
+    	}
+    }
+
+	private void _commonValidateProperties(StatefulEntityType entityType,LinkedHashMap<String,Object> properties) {
+    	ArrayList<String> allowedProps = new ArrayList<String>();
+    	ArrayList<String> requiredProps = new ArrayList<String>();
+    	for(PropertyDef p: entityType.getPropertiesDefObjects()) {
+    		allowedProps.add(p.getName());
+    		// If property is 'required' and has no 'default' value then record
+    		if(p.isRequired() && p.getDefault() == null) {
+    			requiredProps.add(p.getName());
+    		}
+    	}
+        // validate all required properties have values
+        if(properties != null) {
+            ArrayList<String> reqPropsNoValueOrDefault = new ArrayList<String>();
+            _commonValidateField(properties, allowedProps, "properties");
+            // make sure it's not missing any property required by a tosca type
+            for(String r: requiredProps) {
+            	if(properties.get(r) == null) {
+            		reqPropsNoValueOrDefault.add(r);
+            	}
+            }
+            // Required properties found without value or a default value
+            if(!reqPropsNoValueOrDefault.isEmpty()) {
+                ThreadLocalsHolder.getCollector().appendWarning(String.format(
+                    "MissingRequiredFieldError: properties of template \"%s\" are missing field(s): %s",
+                    name,reqPropsNoValueOrDefault.toString()));
+            }
+        }
+        else {
+            // Required properties in schema, but not in template
+            if(!requiredProps.isEmpty()) {
+                ThreadLocalsHolder.getCollector().appendWarning(String.format(
+                        "MissingRequiredFieldError2: properties of template \"%s\" are missing field(s): %s",
+                        name,requiredProps.toString()));
+            }
+        }
+    }
+    
+    @SuppressWarnings("unchecked")
+	private void _validateField(LinkedHashMap<String,Object> template) {
+        if(!(template instanceof LinkedHashMap)) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+            		"MissingRequiredFieldError: Template \"%s\" is missing required field \"%s\"",name,TYPE));
+            return;//???
+        }
+        boolean bBad = false;
+        Object relationship = ((LinkedHashMap<String,Object>)template).get("relationship");
+        if(relationship != null) {
+        	if(!(relationship instanceof String)) {
+        		bBad = (((LinkedHashMap<String,Object>)relationship).get(TYPE) == null);
+        	}
+        	else if(relationship instanceof String) {
+        		bBad = (template.get("relationship") == null);
+        	}
+        }
+        else {
+       		bBad = (template.get(TYPE) == null);
+        }
+        if(bBad) {
+        	ThreadLocalsHolder.getCollector().appendException(String.format(
+            		"MissingRequiredFieldError: Template \"%s\" is missing required field \"%s\"",name,TYPE));
+        }
+    }
+    
+    protected void _commonValidateField(LinkedHashMap<String,Object> schema, ArrayList<String> allowedList,String section) {
+    	for(String sname: schema.keySet()) {
+    		boolean bFound = false;
+    		for(String allowed: allowedList) {
+    			if(sname.equals(allowed)) {
+    				bFound = true;
+    				break;
+    			}
+    		}
+    		if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "UnknownFieldError: Section \"%s\" of template \"%s\" contains unknown field \"%s\"",section,name,sname));
+    		}
+    	}
+    	
+    }
+    
+    @SuppressWarnings("unchecked")
+	private ArrayList<Property> _createProperties() {
+    	ArrayList<Property> props = new ArrayList<Property>();
+    	LinkedHashMap<String,Object> properties = (LinkedHashMap<String,Object>)
+				((EntityType)typeDefinition).getValue(PROPERTIES,entityTpl,false);
+    	if(properties == null) {
+    		properties = new LinkedHashMap<String,Object>();
+    	}
+	   	for(Map.Entry<String,Object> me: properties.entrySet()) {
+	   		String pname = me.getKey();
+	   		Object pvalue = me.getValue();
+	   		LinkedHashMap<String,PropertyDef> propsDef = ((StatefulEntityType)typeDefinition).getPropertiesDef();
+	   		if(propsDef != null && propsDef.get(pname) != null) {
+	   			PropertyDef pd = (PropertyDef)propsDef.get(pname);
+	   			Property prop = new Property(pname,pvalue,pd.getSchema(),customDef);
+	   			props.add(prop);
+	   		}
+	   	}
+	   	ArrayList<PropertyDef> pds = ((StatefulEntityType)typeDefinition).getPropertiesDefObjects();
+	   	for(Object pdo: pds) {
+	   		PropertyDef pd = (PropertyDef)pdo;
+	   		if(pd.getDefault() != null && properties.get(pd.getName()) == null) {
+	   			Property prop = new Property(pd.getName(),pd.getDefault(),pd.getSchema(),customDef);
+	   			props.add(prop);
+	   		}
+	   	}
+	   	return props;
+    }
+
+    @SuppressWarnings("unchecked")
+	private ArrayList<InterfacesDef> _createInterfaces() {
+    	ArrayList<InterfacesDef> interfaces = new ArrayList<>();
+    	LinkedHashMap<String,Object> typeInterfaces = new LinkedHashMap<String,Object>();
+    	if(typeDefinition instanceof RelationshipType) {
+    		if(entityTpl instanceof LinkedHashMap) {
+    			typeInterfaces = (LinkedHashMap<String,Object>)entityTpl.get(INTERFACES);
+    			if(typeInterfaces == null) {
+        		   	for(String relName: entityTpl.keySet()) {
+        		   		Object relValue = entityTpl.get(relName);
+        		   		if(!relName.equals("type")) {
+        		   			Object relDef = relValue;
+        		   			LinkedHashMap<String,Object> rel = null;
+        		   			if(relDef instanceof LinkedHashMap) {
+        		   				Object relob = ((LinkedHashMap<String,Object>)relDef).get("relationship");
+        		   				if(relob instanceof LinkedHashMap) {
+        		   					rel = (LinkedHashMap<String,Object>)relob;
+        		   				}
+        		   			}
+        		   			if(rel != null) {
+        		   				if(rel.get(INTERFACES) != null) {
+        		   					typeInterfaces = (LinkedHashMap<String,Object>)rel.get(INTERFACES);
+        		   					break;
+        		   				}
+        		   			}
+        		   		}
+        		   	}
+    			}
+    		}
+    	}
+    	else {
+    		typeInterfaces = (LinkedHashMap<String,Object>)
+					((EntityType)typeDefinition).getValue(INTERFACES,entityTpl,false);
+    	}
+    	if(typeInterfaces != null) {
+    		for(Map.Entry<String,Object> me: typeInterfaces.entrySet()) {
+    			String interfaceType = me.getKey();
+    		   	LinkedHashMap<String,Object> value = (LinkedHashMap<String,Object>)me.getValue();
+    		   	for(Map.Entry<String,Object> ve: value.entrySet()) {
+    		   		String op = ve.getKey();
+    		   		Object opDef = ve.getValue();
+    		   		InterfacesDef iface = new InterfacesDef((EntityType)typeDefinition,
+    		   												interfaceType,
+    		   												this,
+    		   												op,
+    		   												opDef);
+    		   		interfaces.add(iface);
+    		   	}
+    			
+    		}
+    	}
+    	return interfaces;
+    }
+    
+	public Capability getCapability(String name) {
+        // Provide named capability
+    	// :param name: name of capability
+        // :return: capability object if found, None otherwise
+    	LinkedHashMap<String,Capability> caps = getCapabilities();
+    	if(caps != null) {
+    		return caps.get(name);
+    	}
+    	return null;
+    }
+    
+	// getter
+   public String getName() {
+    	return name;
+    }
+   
+    public StatefulEntityType getTypeDefinition() {
+    	return typeDefinition;
+    }
+   
+	public LinkedHashMap<String,Object> getCustomDef() {
+		return customDef;
+	}
+
+	@Override
+	public String toString() {
+		return "EntityTemplate{" +
+				"name='" + name + '\'' +
+				", entityTpl=" + entityTpl +
+				", customDef=" + customDef +
+				", typeDefinition=" + typeDefinition +
+				", _properties=" + _properties +
+				", _interfaces=" + _interfaces +
+				", _requirements=" + _requirements +
+				", _capabilities=" + _capabilities +
+				'}';
+	}
+}
+
+/*python
+
+class EntityTemplate(object):
+    '''Base class for TOSCA templates.'''
+
+    SECTIONS = (DERIVED_FROM, PROPERTIES, REQUIREMENTS,
+                INTERFACES, CAPABILITIES, TYPE, DESCRIPTION, DIRECTIVES,
+                ATTRIBUTES, ARTIFACTS, NODE_FILTER, COPY) = \
+               ('derived_from', 'properties', 'requirements', 'interfaces',
+                'capabilities', 'type', 'description', 'directives',
+                'attributes', 'artifacts', 'node_filter', 'copy')
+    REQUIREMENTS_SECTION = (NODE, CAPABILITY, RELATIONSHIP, OCCURRENCES, NODE_FILTER) = \
+                           ('node', 'capability', 'relationship',
+                            'occurrences', 'node_filter')
+    # Special key names
+    SPECIAL_SECTIONS = (METADATA) = ('metadata')
+
+    def __init__(self, name, template, entity_name, custom_def=None):
+        self.name = name
+        self.entity_tpl = template
+        self.custom_def = custom_def
+        self._validate_field(self.entity_tpl)
+        type = self.entity_tpl.get('type')
+        UnsupportedType.validate_type(type)
+        if entity_name == 'node_type':
+            self.type_definition = NodeType(type, custom_def) \
+                if type is not None else None
+        if entity_name == 'relationship_type':
+            relationship = template.get('relationship')
+            type = None
+            if relationship and isinstance(relationship, dict):
+                type = relationship.get('type')
+            elif isinstance(relationship, str):
+                type = self.entity_tpl['relationship']
+            else:
+                type = self.entity_tpl['type']
+            UnsupportedType.validate_type(type)
+            self.type_definition = RelationshipType(type,
+                                                    None, custom_def)
+        if entity_name == 'policy_type':
+            if not type:
+                msg = (_('Policy definition of "%(pname)s" must have'
+                       ' a "type" ''attribute.') % dict(pname=name))
+                ExceptionCollector.appendException(
+                    ValidationError(msg))
+
+            self.type_definition = PolicyType(type, custom_def)
+        if entity_name == 'group_type':
+            self.type_definition = GroupType(type, custom_def) \
+                if type is not None else None
+        self._properties = None
+        self._interfaces = None
+        self._requirements = None
+        self._capabilities = None
+
+    @property
+    def type(self):
+        if self.type_definition:
+            return self.type_definition.type
+
+    @property
+    def parent_type(self):
+        if self.type_definition:
+            return self.type_definition.parent_type
+
+    @property
+    def requirements(self):
+        if self._requirements is None:
+            self._requirements = self.type_definition.get_value(
+                self.REQUIREMENTS,
+                self.entity_tpl) or []
+        return self._requirements
+
+    def get_properties_objects(self):
+        '''Return properties objects for this template.'''
+        if self._properties is None:
+            self._properties = self._create_properties()
+        return self._properties
+
+    def get_properties(self):
+        '''Return a dictionary of property name-object pairs.'''
+        return {prop.name: prop
+                for prop in self.get_properties_objects()}
+
+    def get_property_value(self, name):
+        '''Return the value of a given property name.'''
+        props = self.get_properties()
+        if props and name in props.keys():
+            return props[name].value
+
+    @property
+    def interfaces(self):
+        if self._interfaces is None:
+            self._interfaces = self._create_interfaces()
+        return self._interfaces
+
+    def get_capabilities_objects(self):
+        '''Return capabilities objects for this template.'''
+        if not self._capabilities:
+            self._capabilities = self._create_capabilities()
+        return self._capabilities
+
+    def get_capabilities(self):
+        '''Return a dictionary of capability name-object pairs.'''
+        return {cap.name: cap
+                for cap in self.get_capabilities_objects()}
+
+    def is_derived_from(self, type_str):
+        '''Check if object inherits from the given type.
+
+        Returns true if this object is derived from 'type_str'.
+        False otherwise.
+        '''
+        if not self.type:
+            return False
+        elif self.type == type_str:
+            return True
+        elif self.parent_type:
+            return self.parent_type.is_derived_from(type_str)
+        else:
+            return False
+
+    def _create_capabilities(self):
+        capability = []
+        caps = self.type_definition.get_value(self.CAPABILITIES,
+                                              self.entity_tpl, True)
+        if caps:
+            for name, props in caps.items():
+                capabilities = self.type_definition.get_capabilities()
+                if name in capabilities.keys():
+                    c = capabilities[name]
+                    properties = {}
+                    # first use the definition default value
+                    if c.properties:
+                        for property_name in c.properties.keys():
+                            prop_def = c.properties[property_name]
+                            if 'default' in prop_def:
+                                properties[property_name] = prop_def['default']
+                    # then update (if available) with the node properties
+                    if 'properties' in props and props['properties']:
+                        properties.update(props['properties'])
+
+                    cap = Capability(name, properties, c)
+                    capability.append(cap)
+        return capability
+
+    def _validate_properties(self, template, entitytype):
+        properties = entitytype.get_value(self.PROPERTIES, template)
+        self._common_validate_properties(entitytype, properties)
+
+    def _validate_capabilities(self):
+        type_capabilities = self.type_definition.get_capabilities()
+        allowed_caps = \
+            type_capabilities.keys() if type_capabilities else []
+        capabilities = self.type_definition.get_value(self.CAPABILITIES,
+                                                      self.entity_tpl)
+        if capabilities:
+            self._common_validate_field(capabilities, allowed_caps,
+                                        'capabilities')
+            self._validate_capabilities_properties(capabilities)
+
+    def _validate_capabilities_properties(self, capabilities):
+        for cap, props in capabilities.items():
+            capability = self.get_capability(cap)
+            if not capability:
+                continue
+            capabilitydef = capability.definition
+            self._common_validate_properties(capabilitydef,
+                                             props[self.PROPERTIES])
+
+            # validating capability properties values
+            for prop in self.get_capability(cap).get_properties_objects():
+                prop.validate()
+
+                # tODO(srinivas_tadepalli): temporary work around to validate
+                # default_instances until standardized in specification
+                if cap == "scalable" and prop.name == "default_instances":
+                    prop_dict = props[self.PROPERTIES]
+                    min_instances = prop_dict.get("min_instances")
+                    max_instances = prop_dict.get("max_instances")
+                    default_instances = prop_dict.get("default_instances")
+                    if not (min_instances <= default_instances
+                            <= max_instances):
+                        err_msg = ('"properties" of template "%s": '
+                                   '"default_instances" value is not between '
+                                   '"min_instances" and "max_instances".' %
+                                   self.name)
+                        ExceptionCollector.appendException(
+                            ValidationError(message=err_msg))
+
+    def _common_validate_properties(self, entitytype, properties):
+        allowed_props = []
+        required_props = []
+        for p in entitytype.get_properties_def_objects():
+            allowed_props.append(p.name)
+            # If property is 'required' and has no 'default' value then record
+            if p.required and p.default is None:
+                required_props.append(p.name)
+        # validate all required properties have values
+        if properties:
+            req_props_no_value_or_default = []
+            self._common_validate_field(properties, allowed_props,
+                                        'properties')
+            # make sure it's not missing any property required by a tosca type
+            for r in required_props:
+                if r not in properties.keys():
+                    req_props_no_value_or_default.append(r)
+            # Required properties found without value or a default value
+            if req_props_no_value_or_default:
+                ExceptionCollector.appendException(
+                    MissingRequiredFieldError(
+                        what='"properties" of template "%s"' % self.name,
+                        required=req_props_no_value_or_default))
+        else:
+            # Required properties in schema, but not in template
+            if required_props:
+                ExceptionCollector.appendException(
+                    MissingRequiredFieldError(
+                        what='"properties" of template "%s"' % self.name,
+                        required=required_props))
+
+    def _validate_field(self, template):
+        if not isinstance(template, dict):
+            ExceptionCollector.appendException(
+                MissingRequiredFieldError(
+                    what='Template "%s"' % self.name, required=self.TYPE))
+        try:
+            relationship = template.get('relationship')
+            if relationship and not isinstance(relationship, str):
+                relationship[self.TYPE]
+            elif isinstance(relationship, str):
+                template['relationship']
+            else:
+                template[self.TYPE]
+        except KeyError:
+            ExceptionCollector.appendException(
+                MissingRequiredFieldError(
+                    what='Template "%s"' % self.name, required=self.TYPE))
+
+    def _common_validate_field(self, schema, allowedlist, section):
+        for name in schema:
+            if name not in allowedlist:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(
+                        what=('"%(section)s" of template "%(nodename)s"'
+                              % {'section': section, 'nodename': self.name}),
+                        field=name))
+
+    def _create_properties(self):
+        props = []
+        properties = self.type_definition.get_value(self.PROPERTIES,
+                                                    self.entity_tpl) or {}
+        for name, value in properties.items():
+            props_def = self.type_definition.get_properties_def()
+            if props_def and name in props_def:
+                prop = Property(name, value,
+                                props_def[name].schema, self.custom_def)
+                props.append(prop)
+        for p in self.type_definition.get_properties_def_objects():
+            if p.default is not None and p.name not in properties.keys():
+                prop = Property(p.name, p.default, p.schema, self.custom_def)
+                props.append(prop)
+        return props
+
+    def _create_interfaces(self):
+        interfaces = []
+        type_interfaces = None
+        if isinstance(self.type_definition, RelationshipType):
+            if isinstance(self.entity_tpl, dict):
+                if self.INTERFACES in self.entity_tpl:
+                    type_interfaces = self.entity_tpl[self.INTERFACES]
+                else:
+                    for rel_def, value in self.entity_tpl.items():
+                        if rel_def != 'type':
+                            rel_def = self.entity_tpl.get(rel_def)
+                            rel = None
+                            if isinstance(rel_def, dict):
+                                rel = rel_def.get('relationship')
+                            if rel:
+                                if self.INTERFACES in rel:
+                                    type_interfaces = rel[self.INTERFACES]
+                                    break
+        else:
+            type_interfaces = self.type_definition.get_value(self.INTERFACES,
+                                                             self.entity_tpl)
+        if type_interfaces:
+            for interface_type, value in type_interfaces.items():
+                for op, op_def in value.items():
+                    iface = InterfacesDef(self.type_definition,
+                                          interfacetype=interface_type,
+                                          node_template=self,
+                                          name=op,
+                                          value=op_def)
+                    interfaces.append(iface)
+        return interfaces
+
+    def get_capability(self, name):
+        """Provide named capability
+
+        :param name: name of capability
+        :return: capability object if found, None otherwise
+        """
+        caps = self.get_capabilities()
+        if caps and name in caps.keys():
+            return caps[name]
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/Group.java b/src/main/java/org/openecomp/sdc/toscaparser/api/Group.java
new file mode 100644
index 0000000..8ed623f
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/Group.java
@@ -0,0 +1,137 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.Metadata;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.openecomp.sdc.toscaparser.api.utils.ValidateUtils;
+
+public class Group extends EntityTemplate {
+	
+	private static final String TYPE = "type";
+	private static final String METADATA = "metadata";
+	private static final String DESCRIPTION = "description";
+	private static final String PROPERTIES = "properties";
+	private static final String MEMBERS = "members";
+	private static final String INTERFACES = "interfaces";
+	private static final String SECTIONS[] = {
+			TYPE, METADATA, DESCRIPTION, PROPERTIES, MEMBERS, INTERFACES};
+
+	private String name;
+	LinkedHashMap<String,Object> tpl; 
+	ArrayList<NodeTemplate> memberNodes;
+	LinkedHashMap<String,Object> customDef;
+	Metadata metaData;
+	
+
+	public Group(String _name, LinkedHashMap<String, Object> _templates, 
+					ArrayList<NodeTemplate> _memberNodes,
+					LinkedHashMap<String, Object> _customDef) {
+		super(_name, _templates, "group_type", _customDef);
+
+		name = _name;
+        tpl = _templates;
+        if(tpl.get(METADATA) != null) {
+        	Object metadataObject = tpl.get(METADATA);
+        	ValidateUtils.validateMap(metadataObject);
+        	metaData = new Metadata((Map<String,Object>)metadataObject);
+        }
+        memberNodes = _memberNodes;
+        _validateKeys();
+	}
+
+	public Metadata getMetadata() {
+		return metaData;
+	}
+	
+	public ArrayList<String> getMembers() {
+		return (ArrayList<String>)entityTpl.get("members");
+	}
+ 
+	public String getDescription() {
+		return (String)entityTpl.get("description");
+		
+	}
+
+	public ArrayList<NodeTemplate> getMemberNodes() {
+		return memberNodes;
+	}
+
+	private void _validateKeys() {
+		for(String key: entityTpl.keySet()) {
+    		boolean bFound = false;
+    		for(String sect: SECTIONS) {
+    			if(key.equals(sect)) {
+    				bFound = true;
+    				break;
+    			}
+    		}
+    		if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "UnknownFieldError: Groups \"%s\" contains unknown field \"%s\"",
+                        name,key));
+    		}
+		}
+	}
+
+	@Override
+	public String toString() {
+		return "Group{" +
+				"name='" + name + '\'' +
+				", tpl=" + tpl +
+				", memberNodes=" + memberNodes +
+				", customDef=" + customDef +
+				", metaData=" + metaData +
+				'}';
+	}
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.entity_template import EntityTemplate
+from toscaparser.utils import validateutils
+
+SECTIONS = (TYPE, METADATA, DESCRIPTION, PROPERTIES, MEMBERS, INTERFACES) = \
+           ('type', 'metadata', 'description',
+            'properties', 'members', 'interfaces')
+
+
+class Group(EntityTemplate):
+
+    def __init__(self, name, group_templates, member_nodes, custom_defs=None):
+        super(Group, self).__init__(name,
+                                    group_templates,
+                                    'group_type',
+                                    custom_defs)
+        self.name = name
+        self.tpl = group_templates
+        self.meta_data = None
+        if self.METADATA in self.tpl:
+            self.meta_data = self.tpl.get(self.METADATA)
+            validateutils.validate_map(self.meta_data)
+        self.member_nodes = member_nodes
+        self._validate_keys()
+
+    @property
+    def members(self):
+        return self.entity_tpl.get('members')
+
+    @property
+    def description(self):
+        return self.entity_tpl.get('description')
+
+    def get_member_nodes(self):
+        return self.member_nodes
+
+    def _validate_keys(self):
+        for key in self.entity_tpl.keys():
+            if key not in SECTIONS:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Groups "%s"' % self.name,
+                                      field=key))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/ImportsLoader.java b/src/main/java/org/openecomp/sdc/toscaparser/api/ImportsLoader.java
new file mode 100644
index 0000000..a97a360
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/ImportsLoader.java
@@ -0,0 +1,728 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.TypeValidation;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.openecomp.sdc.toscaparser.api.utils.UrlUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.yaml.snakeyaml.Yaml;
+
+import java.io.*;
+import java.net.URL;
+import java.nio.file.Paths;
+import java.util.*;
+
+public class ImportsLoader {
+
+	private static Logger log = LoggerFactory.getLogger(ImportsLoader.class.getName());
+	private static final String FILE = "file";
+	private static final String REPOSITORY = "repository";
+	private static final String NAMESPACE_URI = "namespace_uri";
+	private static final String NAMESPACE_PREFIX = "namespace_prefix";
+    private String IMPORTS_SECTION[] = {FILE, REPOSITORY, NAMESPACE_URI, NAMESPACE_PREFIX};
+	
+	private ArrayList<Object> importslist;
+	private String path;
+	private ArrayList<String> typeDefinitionList;
+	
+	private LinkedHashMap<String,Object> customDefs;
+	private ArrayList<LinkedHashMap<String,Object>> nestedToscaTpls;
+	private LinkedHashMap<String,Object> repositories;
+
+	@SuppressWarnings("unchecked")
+	public ImportsLoader(ArrayList<Object>_importslist,
+						 String _path,
+						 Object _typeDefinitionList,
+						 LinkedHashMap<String,Object> tpl) {
+		
+	        this.importslist = _importslist;
+	        customDefs = new LinkedHashMap<String,Object>();
+	        nestedToscaTpls = new ArrayList<LinkedHashMap<String,Object>>();
+	        if((_path == null || _path.isEmpty()) && tpl == null) {
+	            //msg = _('Input tosca template is not provided.')
+	            //log.warning(msg)
+	            ThreadLocalsHolder.getCollector().appendException("ValidationError: Input tosca template is not provided");
+	        }
+	        
+	        this.path = _path;
+	        this.repositories = new LinkedHashMap<String,Object>();
+
+	        if(tpl != null && tpl.get("repositories") != null) { 
+	        	this.repositories = (LinkedHashMap<String,Object>)tpl.get("repositories");
+	        }
+	        this.typeDefinitionList = new ArrayList<String>();
+	        if(_typeDefinitionList != null) {
+	            if(_typeDefinitionList instanceof ArrayList) {
+	                this.typeDefinitionList = (ArrayList<String>)_typeDefinitionList;
+	            } 
+	            else {
+	                this.typeDefinitionList.add((String)_typeDefinitionList);
+	            }
+	        }
+	        _validateAndLoadImports();
+	}
+
+	public LinkedHashMap<String,Object> getCustomDefs() {
+	        return customDefs;
+	}
+
+    public ArrayList<LinkedHashMap<String,Object>> getNestedToscaTpls() {
+	        return nestedToscaTpls;
+    }
+    
+    @SuppressWarnings({ "unchecked", "unused" })
+	public void _validateAndLoadImports() {
+    	Set<String> importNames = new HashSet<String>();
+    	
+    	if(importslist == null) {
+            //msg = _('"imports" keyname is defined without including templates.')
+            //log.error(msg)
+            ThreadLocalsHolder.getCollector().appendException(
+            		"ValidationError: \"imports\" keyname is defined without including templates");
+            return;
+    	}
+    	
+    	for(Object importDef: importslist) {
+    		String fullFileName = null;
+    		LinkedHashMap<String,Object> customType = null;
+    		if(importDef instanceof LinkedHashMap) {
+    			for(Map.Entry<String,Object> me: ((LinkedHashMap<String,Object>)importDef).entrySet()) {
+    				String importName = me.getKey();
+    				Object importUri = me.getValue();
+    				if(importNames.contains(importName)) {
+                        //msg = (_('Duplicate import name "%s" was found.') % import_name)
+                        //log.error(msg)
+                        ThreadLocalsHolder.getCollector().appendException(String.format(
+                        		"ValidationError: Duplicate import name \"%s\" was found",importName));
+    				}
+    				importNames.add(importName); //???
+
+    				// _loadImportTemplate returns 2 objects
+    				Object ffnct[] = _loadImportTemplate(importName, importUri);
+    				fullFileName = (String)ffnct[0];
+    				customType = (LinkedHashMap<String,Object>)ffnct[1];
+    				String namespacePrefix = "";
+    				if(importUri instanceof LinkedHashMap) {
+    					namespacePrefix = (String)
+    							((LinkedHashMap<String,Object>)importUri).get(NAMESPACE_PREFIX);
+    				}
+    				
+    				if(customType != null) {
+    					TypeValidation tv = new TypeValidation(customType, importDef);
+                        _updateCustomDefs(customType, namespacePrefix);
+					}
+    			}
+    		}
+    		else { // old style of imports
+				// _loadImportTemplate returns 2 objects
+				Object ffnct[] = _loadImportTemplate(null,importDef);
+				fullFileName = (String)ffnct[0];
+				customType = (LinkedHashMap<String,Object>)ffnct[1];
+                if(customType != null) {
+                	TypeValidation tv = new TypeValidation(customType,importDef);
+                    _updateCustomDefs(customType,null);
+                }
+    		}
+            _updateNestedToscaTpls(fullFileName, customType);
+
+    		
+    	}
+    }
+
+    @SuppressWarnings("unchecked")
+	private void _updateCustomDefs(LinkedHashMap<String,Object> customType, String namespacePrefix) {
+    	LinkedHashMap<String,Object> outerCustomTypes;// = new LinkedHashMap<String,Object>();
+    	for(String typeDef: typeDefinitionList) {
+    		if(typeDef.equals("imports")) {
+    			// imports are ArrayList...
+    			customDefs.put("imports",(ArrayList<Object>)customType.get(typeDef));
+    		}
+    		else {
+	    		outerCustomTypes = (LinkedHashMap<String,Object>)customType.get(typeDef);
+	    		if(outerCustomTypes != null) {
+    				if(namespacePrefix != null && !namespacePrefix.isEmpty()) {
+    			    	LinkedHashMap<String,Object> prefixCustomTypes = new LinkedHashMap<String,Object>();
+    	    			for(Map.Entry<String,Object> me: outerCustomTypes.entrySet()) {
+    	    				String typeDefKey = me.getKey();
+    	    				String nameSpacePrefixToKey = namespacePrefix + "." + typeDefKey;
+    	    				prefixCustomTypes.put(nameSpacePrefixToKey, outerCustomTypes.get(typeDefKey));
+    	    			}
+    	    			customDefs.putAll(prefixCustomTypes);
+    				}
+    				else {
+    	    			customDefs.putAll(outerCustomTypes);
+    				}
+	    		}
+    		}
+    	}
+    }
+
+    private void _updateNestedToscaTpls(String fullFileName,LinkedHashMap<String,Object> customTpl) {
+    	if(fullFileName != null && customTpl != null) {
+    		LinkedHashMap<String,Object> tt = new LinkedHashMap<String,Object>();
+    		tt.put(fullFileName, customTpl);
+    		nestedToscaTpls.add(tt);
+    	}
+    }
+
+    private void _validateImportKeys(String importName, LinkedHashMap<String,Object> importUri) {
+    	if(importUri.get(FILE) == null) {
+            //log.warning(_('Missing keyname "file" in import "%(name)s".') % {'name': import_name})
+    		ThreadLocalsHolder.getCollector().appendException(String.format(
+    				"MissingRequiredFieldError: Import of template \"%s\" is missing field %s",importName,FILE));
+    	}
+    	for(String key: importUri.keySet()) {
+    		boolean bFound = false;
+    		for(String is: IMPORTS_SECTION) {
+    			if(is.equals(key)) {
+    				bFound = true;
+    				break;
+    			}
+    		}
+    		if(!bFound) {
+                //log.warning(_('Unknown keyname "%(key)s" error in '
+                //        'imported definition "%(def)s".')
+                //      % {'key': key, 'def': import_name})
+    			ThreadLocalsHolder.getCollector().appendException(String.format(
+    					"UnknownFieldError: Import of template \"%s\" has unknown fiels %s",importName,key));
+    		}
+    	}
+    }
+
+    @SuppressWarnings("unchecked")
+	private Object[] _loadImportTemplate(String importName, Object importUriDef) {
+    	/*
+        This method loads the custom type definitions referenced in "imports"
+        section of the TOSCA YAML template by determining whether each import
+        is specified via a file reference (by relative or absolute path) or a
+        URL reference.
+
+        Possibilities:
+        +----------+--------+------------------------------+
+        | template | import | comment                      |
+        +----------+--------+------------------------------+
+        | file     | file   | OK                           |
+        | file     | URL    | OK                           |
+        | preparsed| file   | file must be a full path     |
+        | preparsed| URL    | OK                           |
+        | URL      | file   | file must be a relative path |
+        | URL      | URL    | OK                           |
+        +----------+--------+------------------------------+
+    	*/
+    	Object al[] = new Object[2];
+
+        boolean shortImportNotation = false;
+        String fileName;
+        String repository;
+        if(importUriDef instanceof LinkedHashMap) {
+            _validateImportKeys(importName, (LinkedHashMap<String,Object>)importUriDef);
+            fileName = (String)((LinkedHashMap<String,Object>)importUriDef).get(FILE);
+            repository = (String)((LinkedHashMap<String,Object>)importUriDef).get(REPOSITORY);
+            if(repository != null) {
+            	if(!repositories.keySet().contains(repository)) {
+                    ThreadLocalsHolder.getCollector().appendException(String.format(
+                    		"InvalidPropertyValueError: Repository \"%s\" not found in \"%s\"",
+                    		repository,repositories.keySet().toString()));
+            	}
+            }
+        }
+        else {
+            fileName = (String)importUriDef;
+            repository = null;
+            shortImportNotation = true;
+        }
+
+        if(fileName == null || fileName.isEmpty()) {
+	        //msg = (_('A template file name is not provided with import '
+	        //         'definition "%(import_name)s".')
+	        //       % {'import_name': import_name})
+	        //log.error(msg)
+	        ThreadLocalsHolder.getCollector().appendException(String.format(
+	        		"ValidationError: A template file name is not provided with import definition \"%s\"",importName));
+	        al[0] = al[1] = null;
+	        return al;
+        }
+
+        if(UrlUtils.validateUrl(fileName)) {
+        	try {
+	            al[0] = fileName;
+        		InputStream input = new URL(fileName).openStream();
+				Yaml yaml = new Yaml();
+				al[1] = yaml.load(input);
+	            return al;
+        	}
+        	catch(IOException e) {
+    	        ThreadLocalsHolder.getCollector().appendException(String.format(
+    	        		"ImportError: \"%s\" loading YAML import from \"%s\"",e.getClass().getSimpleName(),fileName));
+    	        al[0] = al[1] = null;
+    	        return al;
+        	}
+        }
+        else if(repository == null || repository.isEmpty()) {
+        	boolean aFile = false;
+            String importTemplate = null;
+            if(path != null && !path.isEmpty()) {
+            	if(UrlUtils.validateUrl(path)) {
+            		File fp = new File(path);
+            		if(fp.isAbsolute()) {
+            			String msg = String.format(
+                            	"ImportError: Absolute file name \"%s\" cannot be used in the URL-based input template \"%s\"",
+                            	fileName,path);
+                        ThreadLocalsHolder.getCollector().appendException(msg);
+                        al[0] = al[1] = null;
+                        return al;
+            		}
+            		importTemplate = UrlUtils.joinUrl(path,fileName);
+            		aFile = false;
+            	}
+            	else {
+                
+                    aFile = true;
+            		File fp = new File(path);
+            		if(fp.isFile()) {
+                        File fn = new File(fileName);
+            			if(fn.isFile()) {
+                            importTemplate = fileName;
+            			}
+                        else {
+                        	String fullPath = Paths.get(path).toAbsolutePath().getParent().toString() + File.separator + fileName;
+                            File ffp = new File(fullPath);		
+                            if(ffp.isFile()) {
+                                importTemplate = fullPath;
+                            }
+                            else {
+                            	String dirPath = Paths.get(path).toAbsolutePath().getParent().toString();
+                            	String filePath;
+                            	if(Paths.get(fileName).getParent() != null) {
+                            		filePath = Paths.get(fileName).getParent().toString();
+                            	}
+                            	else {
+                            		filePath = "";
+                            	}
+                            	if(!filePath.isEmpty() && dirPath.endsWith(filePath)) {
+                            		String sFileName = Paths.get(fileName).getFileName().toString();
+                            		importTemplate = dirPath + File.separator + sFileName; 
+                            		File fit = new File(importTemplate);
+                            		if(!fit.isFile()) {
+                                        //msg = (_('"%(import_template)s" is'
+                                        //        'not a valid file')
+                                        //      % {'import_template':
+                                        //         import_template})
+                                        //log.error(msg)
+                            			String msg = String.format(
+                                        		"ValueError: \"%s\" is not a valid file",importTemplate);
+                                        ThreadLocalsHolder.getCollector().appendException(msg);
+                                        log.debug("ImportsLoader - _loadImportTemplate - {}", msg);
+                            		}
+                            	}
+                            }
+                        }
+            		}
+            	}	
+            }
+            else {  // template is pre-parsed
+            	File fn = new File(fileName);
+            	if(fn.isAbsolute() && fn.isFile()) {
+            		aFile = true;
+            		importTemplate = fileName;
+            	}
+            	else {
+            		String msg = String.format(
+            			"Relative file name \"%s\" cannot be used in a pre-parsed input template",fileName);
+                   ThreadLocalsHolder.getCollector().appendException("ImportError: " + msg);
+                   al[0] = al[1] = null;
+                   return al;
+            	}
+        	}
+            
+            if(importTemplate == null || importTemplate.isEmpty()) {
+                //log.error(_('Import "%(name)s" is not valid.') %
+                //          {'name': import_uri_def})
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"ImportError: Import \"%s\" is not valid",importUriDef));
+    	        al[0] = al[1] = null;
+    	        return al;
+            }
+            
+            // for now, this must be a file
+            if(!aFile) {
+            	log.error("ImportsLoader - _loadImportTemplate - Error!! Expected a file. importUriDef = {}, importTemplate = {}", importUriDef, importTemplate);
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"ImportError: Import \"%s\" is not a file",importName));
+    	        al[0] = al[1] = null;
+    	        return al;
+            }
+            try {
+	            al[0] = importTemplate;
+				InputStream input = new FileInputStream(new File(importTemplate));
+				Yaml yaml = new Yaml();
+				al[1] = yaml.load(input);
+	            return al;
+            }
+            catch(FileNotFoundException e) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"ImportError: Failed to load YAML from \"%s\"",importName));
+    	        al[0] = al[1] = null;
+    	        return al;
+            }
+            catch(Exception e) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"ImportError: Exception from SnakeYAML file = \"%s\"",importName));
+    	        al[0] = al[1] = null;
+    	        return al;
+            }
+        }
+            	
+        if(shortImportNotation) {
+            //log.error(_('Import "%(name)s" is not valid.') % import_uri_def)
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+            		"ImportError: Import \"%s\" is not valid",importName));
+	        al[0] = al[1] = null;
+	        return al;
+        }
+        
+        String fullUrl = "";
+		String repoUrl = "";
+        if(repository != null && !repository.isEmpty()) {
+        	if(repositories != null) {
+        		for(String repoName: repositories.keySet()) {
+        			if(repoName.equals(repository)) {
+	        			Object repoDef = repositories.get(repoName);
+	        			if(repoDef instanceof String) {
+	        				repoUrl = (String)repoDef;
+	        			}
+	        			else if(repoDef instanceof LinkedHashMap) {
+	        				repoUrl = (String)((LinkedHashMap<String,Object>)repoDef).get("url");
+	        			}
+	                    // Remove leading, ending spaces and strip
+	                    // the last character if "/"
+	        			repoUrl = repoUrl.trim();
+	        			if(repoUrl.endsWith("/")) {
+	        				repoUrl = repoUrl.substring(0,repoUrl.length()-1);
+	        			}
+	        			fullUrl = repoUrl + "/" + fileName;
+	        			break;
+        			}
+        		}
+        	}
+        	if(fullUrl.isEmpty()) {
+                String msg = String.format(
+                	"referenced repository \"%s\" in import definition \"%s\" not found",
+                	repository,importName);
+                ThreadLocalsHolder.getCollector().appendException("ImportError: " + msg);
+   	        	al[0] = al[1] = null;
+   	        	return al;
+        	}
+        }
+        if(UrlUtils.validateUrl(fullUrl)) {
+        	try {
+	            al[0] = fullUrl;
+        		InputStream input = new URL(fullUrl).openStream();
+				Yaml yaml = new Yaml();
+				al[1] = yaml.load(input);
+	            return al;
+        	}
+        	catch(IOException e) {
+    	        ThreadLocalsHolder.getCollector().appendException(String.format(
+    	        		"ImportError: Exception loading YAML import from \"%s\"",fullUrl));
+    	        al[0] = al[1] = null;
+    	        return al;
+        	}
+        }
+        else {
+            String msg = String.format(
+                	"repository URL \"%s\" in import definition \"%s\" is not valid",
+                	repoUrl,importName);
+               ThreadLocalsHolder.getCollector().appendException("ImportError: " + msg);
+        }
+          
+        // if we got here something is wrong with the flow...
+        log.error("ImportsLoader - _loadImportTemplate - got to dead end (importName {})", importName);
+        ThreadLocalsHolder.getCollector().appendException(String.format(
+        		"ImportError: _loadImportTemplate got to dead end (importName %s)\n",importName));
+        al[0] = al[1] = null;
+        return al;
+    }
+
+	@Override
+	public String toString() {
+		return "ImportsLoader{" +
+				"IMPORTS_SECTION=" + Arrays.toString(IMPORTS_SECTION) +
+				", importslist=" + importslist +
+				", path='" + path + '\'' +
+				", typeDefinitionList=" + typeDefinitionList +
+				", customDefs=" + customDefs +
+				", nestedToscaTpls=" + nestedToscaTpls +
+				", repositories=" + repositories +
+				'}';
+	}
+}
+
+/*python
+
+import logging
+import os
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidPropertyValueError
+from toscaparser.common.exception import MissingRequiredFieldError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.common.exception import ValidationError
+from toscaparser.elements.tosca_type_validation import TypeValidation
+from toscaparser.utils.gettextutils import _
+import org.openecomp.sdc.toscaparser.api.utils.urlutils
+import org.openecomp.sdc.toscaparser.api.utils.yamlparser
+
+YAML_LOADER = toscaparser.utils.yamlparser.load_yaml
+log = logging.getLogger("tosca")
+
+
+class ImportsLoader(object):
+
+    IMPORTS_SECTION = (FILE, REPOSITORY, NAMESPACE_URI, NAMESPACE_PREFIX) = \
+                      ('file', 'repository', 'namespace_uri',
+                       'namespace_prefix')
+
+    def __init__(self, importslist, path, type_definition_list=None,
+                 tpl=None):
+        self.importslist = importslist
+        self.custom_defs = {}
+        if not path and not tpl:
+            msg = _('Input tosca template is not provided.')
+            log.warning(msg)
+            ExceptionCollector.appendException(ValidationError(message=msg))
+        self.path = path
+        self.repositories = {}
+        if tpl and tpl.get('repositories'):
+            self.repositories = tpl.get('repositories')
+        self.type_definition_list = []
+        if type_definition_list:
+            if isinstance(type_definition_list, list):
+                self.type_definition_list = type_definition_list
+            else:
+                self.type_definition_list.append(type_definition_list)
+        self._validate_and_load_imports()
+
+    def get_custom_defs(self):
+        return self.custom_defs
+
+    def _validate_and_load_imports(self):
+        imports_names = set()
+
+        if not self.importslist:
+            msg = _('"imports" keyname is defined without including '
+                    'templates.')
+            log.error(msg)
+            ExceptionCollector.appendException(ValidationError(message=msg))
+            return
+
+        for import_def in self.importslist:
+            if isinstance(import_def, dict):
+                for import_name, import_uri in import_def.items():
+                    if import_name in imports_names:
+                        msg = (_('Duplicate import name "%s" was found.') %
+                               import_name)
+                        log.error(msg)
+                        ExceptionCollector.appendException(
+                            ValidationError(message=msg))
+                    imports_names.add(import_name)
+
+                    custom_type = self._load_import_template(import_name,
+                                                             import_uri)
+                    namespace_prefix = None
+                    if isinstance(import_uri, dict):
+                        namespace_prefix = import_uri.get(
+                            self.NAMESPACE_PREFIX)
+                    if custom_type:
+                        TypeValidation(custom_type, import_def)
+                        self._update_custom_def(custom_type, namespace_prefix)
+            else:  # old style of imports
+                custom_type = self._load_import_template(None,
+                                                         import_def)
+                if custom_type:
+                    TypeValidation(
+                        custom_type, import_def)
+                    self._update_custom_def(custom_type, None)
+
+    def _update_custom_def(self, custom_type, namespace_prefix):
+        outer_custom_types = {}
+        for type_def in self.type_definition_list:
+            outer_custom_types = custom_type.get(type_def)
+            if outer_custom_types:
+                if type_def == "imports":
+                    self.custom_defs.update({'imports': outer_custom_types})
+                else:
+                    if namespace_prefix:
+                        prefix_custom_types = {}
+                        for type_def_key in outer_custom_types.keys():
+                            namespace_prefix_to_key = (namespace_prefix +
+                                                       "." + type_def_key)
+                            prefix_custom_types[namespace_prefix_to_key] = \
+                                outer_custom_types[type_def_key]
+                        self.custom_defs.update(prefix_custom_types)
+                    else:
+                        self.custom_defs.update(outer_custom_types)
+
+    def _validate_import_keys(self, import_name, import_uri_def):
+        if self.FILE not in import_uri_def.keys():
+            log.warning(_('Missing keyname "file" in import "%(name)s".')
+                        % {'name': import_name})
+            ExceptionCollector.appendException(
+                MissingRequiredFieldError(
+                    what='Import of template "%s"' % import_name,
+                    required=self.FILE))
+        for key in import_uri_def.keys():
+            if key not in self.IMPORTS_SECTION:
+                log.warning(_('Unknown keyname "%(key)s" error in '
+                              'imported definition "%(def)s".')
+                            % {'key': key, 'def': import_name})
+                ExceptionCollector.appendException(
+                    UnknownFieldError(
+                        what='Import of template "%s"' % import_name,
+                        field=key))
+
+    def _load_import_template(self, import_name, import_uri_def):
+        """Handle custom types defined in imported template files
+
+        This method loads the custom type definitions referenced in "imports"
+        section of the TOSCA YAML template by determining whether each import
+        is specified via a file reference (by relative or absolute path) or a
+        URL reference.
+
+        Possibilities:
+        +----------+--------+------------------------------+
+        | template | import | comment                      |
+        +----------+--------+------------------------------+
+        | file     | file   | OK                           |
+        | file     | URL    | OK                           |
+        | preparsed| file   | file must be a full path     |
+        | preparsed| URL    | OK                           |
+        | URL      | file   | file must be a relative path |
+        | URL      | URL    | OK                           |
+        +----------+--------+------------------------------+
+        """
+        short_import_notation = False
+        if isinstance(import_uri_def, dict):
+            self._validate_import_keys(import_name, import_uri_def)
+            file_name = import_uri_def.get(self.FILE)
+            repository = import_uri_def.get(self.REPOSITORY)
+            repos = self.repositories.keys()
+            if repository is not None:
+                if repository not in repos:
+                    ExceptionCollector.appendException(
+                        InvalidPropertyValueError(
+                            what=_('Repository is not found in "%s"') % repos))
+        else:
+            file_name = import_uri_def
+            repository = None
+            short_import_notation = True
+
+        if not file_name:
+            msg = (_('A template file name is not provided with import '
+                     'definition "%(import_name)s".')
+                   % {'import_name': import_name})
+            log.error(msg)
+            ExceptionCollector.appendException(ValidationError(message=msg))
+            return
+
+        if toscaparser.utils.urlutils.UrlUtils.validate_url(file_name):
+            return YAML_LOADER(file_name, False)
+        elif not repository:
+            import_template = None
+            if self.path:
+                if toscaparser.utils.urlutils.UrlUtils.validate_url(self.path):
+                    if os.path.isabs(file_name):
+                        msg = (_('Absolute file name "%(name)s" cannot be '
+                                 'used in a URL-based input template '
+                                 '"%(template)s".')
+                               % {'name': file_name, 'template': self.path})
+                        log.error(msg)
+                        ExceptionCollector.appendException(ImportError(msg))
+                        return
+                    import_template = toscaparser.utils.urlutils.UrlUtils.\
+                        join_url(self.path, file_name)
+                    a_file = False
+                else:
+                    a_file = True
+                    main_a_file = os.path.isfile(self.path)
+
+                    if main_a_file:
+                        if os.path.isfile(file_name):
+                            import_template = file_name
+                        else:
+                            full_path = os.path.join(
+                                os.path.dirname(os.path.abspath(self.path)),
+                                file_name)
+                            if os.path.isfile(full_path):
+                                import_template = full_path
+                            else:
+                                file_path = file_name.rpartition("/")
+                                dir_path = os.path.dirname(os.path.abspath(
+                                    self.path))
+                                if file_path[0] != '' and dir_path.endswith(
+                                    file_path[0]):
+                                        import_template = dir_path + "/" +\
+                                            file_path[2]
+                                        if not os.path.isfile(import_template):
+                                            msg = (_('"%(import_template)s" is'
+                                                     'not a valid file')
+                                                   % {'import_template':
+                                                      import_template})
+                                            log.error(msg)
+                                            ExceptionCollector.appendException
+                                            (ValueError(msg))
+            else:  # template is pre-parsed
+                if os.path.isabs(file_name) and os.path.isfile(file_name):
+                    a_file = True
+                    import_template = file_name
+                else:
+                    msg = (_('Relative file name "%(name)s" cannot be used '
+                             'in a pre-parsed input template.')
+                           % {'name': file_name})
+                    log.error(msg)
+                    ExceptionCollector.appendException(ImportError(msg))
+                    return
+
+            if not import_template:
+                log.error(_('Import "%(name)s" is not valid.') %
+                          {'name': import_uri_def})
+                ExceptionCollector.appendException(
+                    ImportError(_('Import "%s" is not valid.') %
+                                import_uri_def))
+                return
+            return YAML_LOADER(import_template, a_file)
+
+        if short_import_notation:
+            log.error(_('Import "%(name)s" is not valid.') % import_uri_def)
+            ExceptionCollector.appendException(
+                ImportError(_('Import "%s" is not valid.') % import_uri_def))
+            return
+
+        full_url = ""
+        if repository:
+            if self.repositories:
+                for repo_name, repo_def in self.repositories.items():
+                    if repo_name == repository:
+                        # Remove leading, ending spaces and strip
+                        # the last character if "/"
+                        repo_url = ((repo_def['url']).strip()).rstrip("//")
+                        full_url = repo_url + "/" + file_name
+
+            if not full_url:
+                msg = (_('referenced repository "%(n_uri)s" in import '
+                         'definition "%(tpl)s" not found.')
+                       % {'n_uri': repository, 'tpl': import_name})
+                log.error(msg)
+                ExceptionCollector.appendException(ImportError(msg))
+                return
+
+        if toscaparser.utils.urlutils.UrlUtils.validate_url(full_url):
+            return YAML_LOADER(full_url, False)
+        else:
+            msg = (_('repository url "%(n_uri)s" is not valid in import '
+                     'definition "%(tpl)s".')
+                   % {'n_uri': repo_url, 'tpl': import_name})
+            log.error(msg)
+            ExceptionCollector.appendException(ImportError(msg))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/NodeTemplate.java b/src/main/java/org/openecomp/sdc/toscaparser/api/NodeTemplate.java
new file mode 100644
index 0000000..c8af559
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/NodeTemplate.java
@@ -0,0 +1,755 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.*;
+import org.openecomp.sdc.toscaparser.api.utils.CopyUtils;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class NodeTemplate extends EntityTemplate {
+	
+	private LinkedHashMap<String,Object> templates;
+	private LinkedHashMap<String,Object> customDef;
+	private ArrayList<RelationshipTemplate> availableRelTpls;
+	private LinkedHashMap<String,Object> availableRelTypes;
+	private LinkedHashMap<NodeTemplate,RelationshipType> related;
+	private ArrayList<RelationshipTemplate> relationshipTpl;
+	private LinkedHashMap<RelationshipType,NodeTemplate> _relationships;
+	private SubstitutionMappings subMappingToscaTemplate;
+	private SubstitutionMappings subMappingToscaTemplate2;
+	private Metadata metadata;
+
+	private static final String METADATA = "metadata";
+
+	@SuppressWarnings("unchecked")
+	public NodeTemplate(String name,
+						LinkedHashMap<String,Object> ntnodeTemplates,
+						LinkedHashMap<String,Object> ntcustomDef,
+						ArrayList<RelationshipTemplate> ntavailableRelTpls,
+						LinkedHashMap<String,Object> ntavailableRelTypes) {
+		
+       super(name, (LinkedHashMap<String,Object>)ntnodeTemplates.get(name), "node_type", ntcustomDef);
+
+       templates = ntnodeTemplates;
+       _validateFields((LinkedHashMap<String,Object>)templates.get(name));
+       customDef = ntcustomDef;
+       related = new LinkedHashMap<NodeTemplate,RelationshipType>();
+       relationshipTpl = new ArrayList<RelationshipTemplate>();
+       availableRelTpls = ntavailableRelTpls;
+       availableRelTypes = ntavailableRelTypes;
+       _relationships = new LinkedHashMap<RelationshipType,NodeTemplate>();
+       subMappingToscaTemplate = null;
+       subMappingToscaTemplate2 = null;
+       metadata = _metaData();
+	}
+
+	@SuppressWarnings("unchecked")
+	public LinkedHashMap<RelationshipType,NodeTemplate> getRelationships() {
+		if(_relationships.isEmpty()) {
+			ArrayList<Object> requires = getRequirements();
+			if(requires != null && requires instanceof ArrayList) {
+				for(Object ro: requires) {
+					LinkedHashMap<String,Object> r = (LinkedHashMap<String,Object>)ro;
+					for(Map.Entry<String,Object> me: r.entrySet()) {
+						LinkedHashMap<RelationshipType,NodeTemplate> explicit = _getExplicitRelationship(r,me.getValue());
+						if(explicit != null) {
+							// _relationships.putAll(explicit)...
+							for(Map.Entry<RelationshipType,NodeTemplate> ee: explicit.entrySet()) {
+								_relationships.put(ee.getKey(), ee.getValue());
+							}
+						}
+					}
+				}
+			}
+		}
+		return _relationships;
+	}
+
+	@SuppressWarnings("unchecked")
+	private LinkedHashMap<RelationshipType,NodeTemplate> _getExplicitRelationship(LinkedHashMap<String,Object> req,Object value) {
+        // Handle explicit relationship
+
+        // For example,
+        // - req:
+        //     node: DBMS
+        //     relationship: tosca.relationships.HostedOn
+		
+		LinkedHashMap<RelationshipType,NodeTemplate> explicitRelation = new LinkedHashMap<RelationshipType,NodeTemplate>();
+		String node;
+		if(value instanceof LinkedHashMap) {
+			node = (String)((LinkedHashMap<String,Object>)value).get("node");
+		}
+		else {
+			node = (String)value;
+		}
+		
+		if(node != null && !node.isEmpty()) {
+            //msg = _('Lookup by TOSCA types is not supported. '
+            //        'Requirement for "%s" can not be full-filled.') % self.name
+			boolean bFound = false;
+			for(String k: EntityType.TOSCA_DEF.keySet()) {
+				if(k.equals(node)) {
+					bFound = true;
+					break;
+				}
+			}
+			if(bFound || customDef.get(node) != null) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"NotImplementedError: Lookup by TOSCA types is not supported. Requirement for \"%s\" can not be full-filled",
+                		getName()));
+                return null;
+			}
+			if(templates.get(node) == null) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "KeyError: Node template \"%s\" was not found",node));
+                    return null;
+			}
+			NodeTemplate relatedTpl = new NodeTemplate(node,templates,customDef,null,null);
+			Object relationship = null;
+			String relationshipString = null;
+			if(value instanceof LinkedHashMap) {
+				relationship = ((LinkedHashMap<String,Object>)value).get("relationship");
+				// here relationship can be a string or a LHM with 'type':<relationship>
+			}
+            // check if its type has relationship defined
+			if(relationship == null) {
+				ArrayList<Object> parentReqs = ((NodeType)typeDefinition).getAllRequirements();
+				if(parentReqs == null) {
+                    ThreadLocalsHolder.getCollector().appendException("ValidationError: parent_req is null");
+				}
+				else {
+					for(String key: req.keySet()) {
+						boolean bFoundRel = false;
+						for(Object rdo: parentReqs) {
+							LinkedHashMap<String,Object> reqDict = (LinkedHashMap<String,Object>)rdo;
+							LinkedHashMap<String,Object> relDict = (LinkedHashMap<String,Object>)reqDict.get(key);
+							if(relDict != null) {
+								relationship = relDict.get("relationship");
+								//BUG-python??? need to break twice?
+								bFoundRel = true;
+								break;
+							}
+						}
+						if(bFoundRel) {
+							break;
+						}
+					}
+				}
+			}
+			
+			if(relationship != null) {
+				// here relationship can be a string or a LHM with 'type':<relationship>
+				if(relationship instanceof String) {
+					relationshipString = (String)relationship;
+				}
+				else if(relationship instanceof LinkedHashMap) {
+					relationshipString = (String)((LinkedHashMap<String,Object>)relationship).get("type");
+				}
+				
+				boolean foundRelationshipTpl = false;
+				// apply available relationship templates if found
+				if(availableRelTpls != null) {
+					for(RelationshipTemplate tpl: availableRelTpls) {
+						if(tpl.getName().equals(relationshipString)) {
+							RelationshipType rtype = new RelationshipType(tpl.getType(),null,customDef);
+							explicitRelation.put(rtype, relatedTpl);
+							tpl.setTarget(relatedTpl);
+							tpl.setSource(this);
+							relationshipTpl.add(tpl);
+							foundRelationshipTpl = true;
+						}
+					}
+				}
+				// create relationship template object.
+				String relPrfx = EntityType.RELATIONSHIP_PREFIX;
+				if(!foundRelationshipTpl) {
+					if(relationship instanceof LinkedHashMap) {
+            	   	   	relationshipString = (String)((LinkedHashMap<String,Object>)relationship).get("type");
+            	   	   	if(relationshipString != null) {
+            	   	   		if(availableRelTypes != null && !availableRelTypes.isEmpty() && 
+            	   	   				availableRelTypes.get(relationshipString) != null) {
+            	   	   			;
+            	   	   		}
+            	   	   		else if(!(relationshipString).startsWith(relPrfx)) {
+            	   	   			relationshipString = relPrfx + relationshipString;
+            	   	   		}
+            	   	   	}
+            	   	   	else {
+            	   	   			ThreadLocalsHolder.getCollector().appendException(String.format(
+            	   	   					"MissingRequiredFieldError: \"relationship\" used in template \"%s\" is missing required field \"type\"",
+            	   	   					relatedTpl.getName()));
+            		   	}
+            	   }
+            	   for(RelationshipType rtype: ((NodeType)typeDefinition).getRelationship().keySet()) {
+            		   if(rtype.getType().equals(relationshipString)) {
+            			   explicitRelation.put(rtype,relatedTpl);
+            			   relatedTpl._addRelationshipTemplate(req,rtype.getType(),this);
+            		   }
+            		   else if(availableRelTypes != null && !availableRelTypes.isEmpty()) {
+            			   LinkedHashMap<String,Object> relTypeDef = (LinkedHashMap<String,Object>)availableRelTypes.get(relationshipString);
+            			   if(relTypeDef != null) {
+            				   String superType = (String)relTypeDef.get("derived_from");
+            				   if(superType != null) {
+            					   if(!superType.startsWith(relPrfx)) {
+            						   superType = relPrfx + superType;
+            					   }
+            					   if(rtype.getType().equals(superType)) {
+                        			   explicitRelation.put(rtype,relatedTpl);
+                        			   relatedTpl._addRelationshipTemplate(req,rtype.getType(),this);
+            					   }
+            				   }
+            			   }
+            		   }
+            	   }
+               }
+			}
+		}
+		return explicitRelation;
+	}
+
+	@SuppressWarnings("unchecked")
+	private void _addRelationshipTemplate(LinkedHashMap<String,Object> requirement, String rtype, NodeTemplate source) {
+		LinkedHashMap<String,Object> req = (LinkedHashMap<String,Object>)CopyUtils.copyLhmOrAl(requirement);
+		req.put("type",rtype);
+		RelationshipTemplate tpl = new RelationshipTemplate(req, rtype, customDef, this, source);
+		relationshipTpl.add(tpl);
+	}
+
+	public ArrayList<RelationshipTemplate> getRelationshipTemplate() {
+		return relationshipTpl;
+	}
+
+	void _addNext(NodeTemplate nodetpl,RelationshipType relationship) {
+		related.put(nodetpl,relationship);
+	}
+	
+	public ArrayList<NodeTemplate> getRelatedNodes() {
+		if(related.isEmpty()) { 
+			for(Map.Entry<RelationshipType,NodeType> me: ((NodeType)typeDefinition).getRelationship().entrySet()) {
+				RelationshipType relation = me.getKey();
+				NodeType node = me.getValue();
+				for(String tpl: templates.keySet()) {
+					if(tpl.equals(node.getType())) {
+						//BUG.. python has
+						//    self.related[NodeTemplate(tpl)] = relation
+						// but NodeTemplate doesn't have a constructor with just name...
+						//????		
+						related.put(new NodeTemplate(tpl,null,null,null,null),relation);
+					}
+				}
+			}
+		}
+		return new ArrayList<NodeTemplate>(related.keySet());
+	}
+
+	public void validate(/*tosca_tpl=none is not used...*/) {
+        _validateCapabilities();
+        _validateRequirements();
+        _validateProperties(entityTpl,(NodeType)typeDefinition);
+        _validateInterfaces();
+        for(Property prop: getPropertiesObjects()) {
+        	prop.validate();
+        }
+	}
+
+	private Metadata _metaData() {
+		if(entityTpl.get(METADATA) != null) {
+			return new Metadata((Map<String,Object>)entityTpl.get(METADATA));
+		}
+		else {
+			return null;
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	private void _validateRequirements() {
+		ArrayList<Object> typeRequires = ((NodeType)typeDefinition).getAllRequirements();
+		ArrayList<String> allowedReqs = new ArrayList<>();
+		allowedReqs.add("template");
+		if(typeRequires != null) {
+			for(Object to: typeRequires) {
+				LinkedHashMap<String,Object> treq = (LinkedHashMap<String,Object>)to;
+				for(Map.Entry<String,Object> me: treq.entrySet()) {
+					String key = me.getKey();
+					Object  value = me.getValue();
+					allowedReqs.add(key);
+					if(value instanceof LinkedHashMap) {
+						allowedReqs.addAll(((LinkedHashMap<String,Object>)value).keySet());
+					}
+				}
+				
+			}
+		}
+		
+		ArrayList<Object> requires = (ArrayList<Object>)((NodeType)typeDefinition).getValue(REQUIREMENTS, entityTpl, false);
+		if(requires != null) {
+			if(!(requires instanceof ArrayList)) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "TypeMismatchError: \"requirements\" of template \"%s\" are not of type \"list\"",name));
+			}
+			else {
+                for(Object ro: requires) {
+                	LinkedHashMap<String,Object> req = (LinkedHashMap<String,Object>)ro;
+                	for(Map.Entry<String,Object> me: req.entrySet()) {
+                		String rl = me.getKey();
+                		Object vo = me.getValue();
+                		if(vo instanceof LinkedHashMap) {
+                    		LinkedHashMap<String,Object> value = (LinkedHashMap<String,Object>)vo;
+                			_validateRequirementsKeys(value);
+                			_validateRequirementsProperties(value);
+                			allowedReqs.add(rl);
+                		}
+                	}
+                	_commonValidateField(req,allowedReqs,"requirements");
+                }
+			}
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	private void _validateRequirementsProperties(LinkedHashMap<String,Object> reqs) {
+        // TO-DO(anyone): Only occurrences property of the requirements is
+        // validated here. Validation of other requirement properties are being
+        // validated in different files. Better to keep all the requirements
+        // properties validation here.
+		for(Map.Entry<String,Object> me: reqs.entrySet()) {
+			if(me.getKey().equals("occurrences")) {
+				ArrayList<Object> val = (ArrayList<Object>)me.getValue();
+				_validateOccurrences(val);
+			}
+			
+		}
+	}
+	
+	private void _validateOccurrences(ArrayList<Object> occurrences) {
+        DataEntity.validateDatatype("list",occurrences,null,null,null);
+        for(Object val: occurrences) {
+            DataEntity.validateDatatype("Integer",val,null,null,null);
+        }
+        if(occurrences.size() != 2 || 
+           !(0 <= (int)occurrences.get(0)  && (int)occurrences.get(0) <= (int)occurrences.get(1)) ||
+           (int)occurrences.get(1) == 0) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                "InvalidPropertyValueError: property has invalid value %s",occurrences.toString()));
+        }
+	}
+	
+	private void _validateRequirementsKeys(LinkedHashMap<String,Object> reqs) {
+		for(String key: reqs.keySet()) {
+			boolean bFound = false;
+			for(int i=0; i< REQUIREMENTS_SECTION.length; i++) {
+				if(key.equals(REQUIREMENTS_SECTION[i])) {
+					bFound = true;
+					break;
+				}
+			}
+			if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "UnknownFieldError: \"requirements\" of template \"%s\" contains unknown field \"%s\"",name,key));
+			}
+		}
+	}
+	
+	@SuppressWarnings("unchecked")
+	private void _validateInterfaces() {
+		LinkedHashMap<String,Object> ifaces = (LinkedHashMap<String,Object>)
+				((NodeType)typeDefinition).getValue(INTERFACES, entityTpl, false);
+		if(ifaces != null) {
+			for(Map.Entry<String,Object> me: ifaces.entrySet()) {
+				String iname = me.getKey();
+				LinkedHashMap<String,Object> value = (LinkedHashMap<String,Object>)me.getValue();
+				if(iname.equals(InterfacesDef.LIFECYCLE) || iname.equals(InterfacesDef.LIFECYCLE_SHORTNAME)) {
+					// maybe we should convert [] to arraylist???
+					ArrayList<String> inlo = new ArrayList<>();
+					for(int i=0; i<InterfacesDef.interfacesNodeLifecycleOperations.length; i++) {
+						inlo.add(InterfacesDef.interfacesNodeLifecycleOperations[i]);
+					}
+                    _commonValidateField(value,inlo,"interfaces");
+                }
+				else if(iname.equals(InterfacesDef.CONFIGURE) || iname.equals(InterfacesDef.CONFIGURE_SHORTNAME)) {
+					// maybe we should convert [] to arraylist???
+					ArrayList<String> irco = new ArrayList<>();
+					for(int i=0; i<InterfacesDef.interfacesRelationshipConfigureOperations.length; i++) {
+						irco.add(InterfacesDef.interfacesRelationshipConfigureOperations[i]);
+					}
+                    _commonValidateField(value,irco,"interfaces");
+                }
+				else if(((NodeType)typeDefinition).getInterfaces().keySet().contains(iname)) {
+					_commonValidateField(value,_collectCustomIfaceOperations(iname),"interfaces");
+				}
+				else {
+                    ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "UnknownFieldError: \"interfaces\" of template \"%s\" contains unknown field %s",name,iname));
+				}
+			}
+		}
+	}
+	
+	@SuppressWarnings("unchecked")
+	private ArrayList<String> _collectCustomIfaceOperations(String iname) {
+		ArrayList<String> allowedOperations = new ArrayList<>();
+		LinkedHashMap<String,Object> nodetypeIfaceDef = (LinkedHashMap<String,Object>)((NodeType)
+															typeDefinition).getInterfaces().get(iname);
+		allowedOperations.addAll(nodetypeIfaceDef.keySet());
+		String ifaceType = (String)nodetypeIfaceDef.get("type");
+		if(ifaceType != null) {
+			LinkedHashMap<String,Object> ifaceTypeDef = null;
+			if(((NodeType)typeDefinition).customDef != null) {
+				ifaceTypeDef = (LinkedHashMap<String,Object>)((NodeType)typeDefinition).customDef.get(ifaceType);
+			}
+			if(ifaceTypeDef == null) {
+				ifaceTypeDef = (LinkedHashMap<String,Object>)EntityType.TOSCA_DEF.get(ifaceType);
+			}
+			allowedOperations.addAll(ifaceTypeDef.keySet());
+		}
+		// maybe we should convert [] to arraylist???
+		ArrayList<String> idrw = new ArrayList<>();
+		for(int i=0; i<InterfacesDef.INTERFACE_DEF_RESERVED_WORDS.length; i++) {
+			idrw.add(InterfacesDef.INTERFACE_DEF_RESERVED_WORDS[i]);
+		}
+		allowedOperations.removeAll(idrw);
+		return allowedOperations;
+	}
+
+	private void _validateFields(LinkedHashMap<String,Object> nodetemplate) {
+		for(String ntname: nodetemplate.keySet()) {
+			boolean bFound = false;
+			for(int i=0; i< SECTIONS.length; i++) {
+				if(ntname.equals(SECTIONS[i])) {
+					bFound = true;
+					break;
+				}
+			}
+			if(!bFound) {
+				for(int i=0; i< SPECIAL_SECTIONS.length; i++) {
+					if(ntname.equals(SPECIAL_SECTIONS[i])) {
+						bFound = true;
+						break;
+					}
+				}
+				
+			}
+			if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+	                    "UnknownFieldError: Node template \"%s\" has unknown field \"%s\"",name,ntname));
+			}
+		}
+	}
+	
+	// getter/setter
+	
+	public SubstitutionMappings getSubMappingToscaTemplate() {
+		return subMappingToscaTemplate;
+	}
+	
+	public void setSubMappingToscaTemplate(SubstitutionMappings sm) {
+		subMappingToscaTemplate = sm;
+	}
+	
+	// **experimental** (multilevel nesting)
+	public SubstitutionMappings getSubMappingToscaTemplate2() {
+		return subMappingToscaTemplate2;
+	}
+	
+	public void setSubMappingToscaTemplate2(SubstitutionMappings sm) {
+		subMappingToscaTemplate2 = sm;
+	}
+	
+	public Metadata getMetaData() {
+		return metadata;
+	}
+
+	public void setMetaData(Metadata metadata) {
+		this.metadata = metadata;
+	}
+
+	@Override
+	public String toString() {
+		return getName();
+	}
+
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidPropertyValueError
+from toscaparser.common.exception import MissingRequiredFieldError
+from toscaparser.common.exception import TypeMismatchError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.common.exception import ValidationError
+from toscaparser.dataentity import DataEntity
+from toscaparser.elements.interfaces import CONFIGURE
+from toscaparser.elements.interfaces import CONFIGURE_SHORTNAME
+from toscaparser.elements.interfaces import INTERFACE_DEF_RESERVED_WORDS
+from toscaparser.elements.interfaces import InterfacesDef
+from toscaparser.elements.interfaces import LIFECYCLE
+from toscaparser.elements.interfaces import LIFECYCLE_SHORTNAME
+from toscaparser.elements.relationshiptype import RelationshipType
+from toscaparser.entity_template import EntityTemplate
+from toscaparser.relationship_template import RelationshipTemplate
+from toscaparser.utils.gettextutils import _
+
+log = logging.getLogger('tosca')
+
+
+class NodeTemplate(EntityTemplate):
+    '''Node template from a Tosca profile.'''
+    def __init__(self, name, node_templates, custom_def=None,
+                 available_rel_tpls=None, available_rel_types=None):
+        super(NodeTemplate, self).__init__(name, node_templates[name],
+                                           'node_type',
+                                           custom_def)
+        self.templates = node_templates
+        self._validate_fields(node_templates[name])
+        self.custom_def = custom_def
+        self.related = {}
+        self.relationship_tpl = []
+        self.available_rel_tpls = available_rel_tpls
+        self.available_rel_types = available_rel_types
+        self._relationships = {}
+        self.sub_mapping_tosca_template = None
+
+    @property
+    def relationships(self):
+        if not self._relationships:
+            requires = self.requirements
+            if requires and isinstance(requires, list):
+                for r in requires:
+                    for r1, value in r.items():
+                        explicit = self._get_explicit_relationship(r, value)
+                        if explicit:
+                            for key, value in explicit.items():
+                                self._relationships[key] = value
+        return self._relationships
+
+    def _get_explicit_relationship(self, req, value):
+        """Handle explicit relationship
+
+        For example,
+        - req:
+            node: DBMS
+            relationship: tosca.relationships.HostedOn
+        """
+        explicit_relation = {}
+        node = value.get('node') if isinstance(value, dict) else value
+
+        if node:
+            # TO-DO(spzala) implement look up once Glance meta data is available
+            # to find a matching TOSCA node using the TOSCA types
+            msg = _('Lookup by TOSCA types is not supported. '
+                    'Requirement for "%s" can not be full-filled.') % self.name
+            if (node in list(self.type_definition.TOSCA_DEF.keys())
+               or node in self.custom_def):
+                ExceptionCollector.appendException(NotImplementedError(msg))
+                return
+
+            if node not in self.templates:
+                ExceptionCollector.appendException(
+                    KeyError(_('Node template "%s" was not found.') % node))
+                return
+
+            related_tpl = NodeTemplate(node, self.templates, self.custom_def)
+            relationship = value.get('relationship') \
+                if isinstance(value, dict) else None
+            # check if it's type has relationship defined
+            if not relationship:
+                parent_reqs = self.type_definition.get_all_requirements()
+                if parent_reqs is None:
+                    ExceptionCollector.appendException(
+                        ValidationError(message='parent_req is ' +
+                                        str(parent_reqs)))
+                else:
+                    for key in req.keys():
+                        for req_dict in parent_reqs:
+                            if key in req_dict.keys():
+                                relationship = (req_dict.get(key).
+                                                get('relationship'))
+                                break
+            if relationship:
+                found_relationship_tpl = False
+                # apply available relationship templates if found
+                if self.available_rel_tpls:
+                    for tpl in self.available_rel_tpls:
+                        if tpl.name == relationship:
+                            rtype = RelationshipType(tpl.type, None,
+                                                     self.custom_def)
+                            explicit_relation[rtype] = related_tpl
+                            tpl.target = related_tpl
+                            tpl.source = self
+                            self.relationship_tpl.append(tpl)
+                            found_relationship_tpl = True
+                # create relationship template object.
+                rel_prfx = self.type_definition.RELATIONSHIP_PREFIX
+                if not found_relationship_tpl:
+                    if isinstance(relationship, dict):
+                        relationship = relationship.get('type')
+                        if relationship:
+                            if self.available_rel_types and \
+                               relationship in self.available_rel_types.keys():
+                                pass
+                            elif not relationship.startswith(rel_prfx):
+                                relationship = rel_prfx + relationship
+                        else:
+                            ExceptionCollector.appendException(
+                                MissingRequiredFieldError(
+                                    what=_('"relationship" used in template '
+                                           '"%s"') % related_tpl.name,
+                                    required=self.TYPE))
+                    for rtype in self.type_definition.relationship.keys():
+                        if rtype.type == relationship:
+                            explicit_relation[rtype] = related_tpl
+                            related_tpl._add_relationship_template(req,
+                                                                   rtype.type,
+                                                                   self)
+                        elif self.available_rel_types:
+                            if relationship in self.available_rel_types.keys():
+                                rel_type_def = self.available_rel_types.\
+                                    get(relationship)
+                                if 'derived_from' in rel_type_def:
+                                    super_type = \
+                                        rel_type_def.get('derived_from')
+                                    if not super_type.startswith(rel_prfx):
+                                        super_type = rel_prfx + super_type
+                                    if rtype.type == super_type:
+                                        explicit_relation[rtype] = related_tpl
+                                        related_tpl.\
+                                            _add_relationship_template(
+                                                req, rtype.type, self)
+        return explicit_relation
+
+    def _add_relationship_template(self, requirement, rtype, source):
+        req = requirement.copy()
+        req['type'] = rtype
+        tpl = RelationshipTemplate(req, rtype, self.custom_def, self, source)
+        self.relationship_tpl.append(tpl)
+
+    def get_relationship_template(self):
+        return self.relationship_tpl
+
+    def _add_next(self, nodetpl, relationship):
+        self.related[nodetpl] = relationship
+
+    @property
+    def related_nodes(self):
+        if not self.related:
+            for relation, node in self.type_definition.relationship.items():
+                for tpl in self.templates:
+                    if tpl == node.type:
+                        self.related[NodeTemplate(tpl)] = relation
+        return self.related.keys()
+
+    def validate(self, tosca_tpl=None):
+        self._validate_capabilities()
+        self._validate_requirements()
+        self._validate_properties(self.entity_tpl, self.type_definition)
+        self._validate_interfaces()
+        for prop in self.get_properties_objects():
+            prop.validate()
+
+    def _validate_requirements(self):
+        type_requires = self.type_definition.get_all_requirements()
+        allowed_reqs = ["template"]
+        if type_requires:
+            for treq in type_requires:
+                for key, value in treq.items():
+                    allowed_reqs.append(key)
+                    if isinstance(value, dict):
+                        for key in value:
+                            allowed_reqs.append(key)
+
+        requires = self.type_definition.get_value(self.REQUIREMENTS,
+                                                  self.entity_tpl)
+        if requires:
+            if not isinstance(requires, list):
+                ExceptionCollector.appendException(
+                    TypeMismatchError(
+                        what='"requirements" of template "%s"' % self.name,
+                        type='list'))
+            else:
+                for req in requires:
+                    for r1, value in req.items():
+                        if isinstance(value, dict):
+                            self._validate_requirements_keys(value)
+                            self._validate_requirements_properties(value)
+                            allowed_reqs.append(r1)
+                    self._common_validate_field(req, allowed_reqs,
+                                                'requirements')
+
+    def _validate_requirements_properties(self, requirements):
+        # TO-DO(anyone): Only occurrences property of the requirements is
+        # validated here. Validation of other requirement properties are being
+        # validated in different files. Better to keep all the requirements
+        # properties validation here.
+        for key, value in requirements.items():
+            if key == 'occurrences':
+                self._validate_occurrences(value)
+                break
+
+    def _validate_occurrences(self, occurrences):
+        DataEntity.validate_datatype('list', occurrences)
+        for value in occurrences:
+            DataEntity.validate_datatype('integer', value)
+        if len(occurrences) != 2 or not (0 <= occurrences[0] <= occurrences[1]) \
+                or occurrences[1] == 0:
+            ExceptionCollector.appendException(
+                InvalidPropertyValueError(what=(occurrences)))
+
+    def _validate_requirements_keys(self, requirement):
+        for key in requirement.keys():
+            if key not in self.REQUIREMENTS_SECTION:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(
+                        what='"requirements" of template "%s"' % self.name,
+                        field=key))
+
+    def _validate_interfaces(self):
+        ifaces = self.type_definition.get_value(self.INTERFACES,
+                                                self.entity_tpl)
+        if ifaces:
+            for name, value in ifaces.items():
+                if name in (LIFECYCLE, LIFECYCLE_SHORTNAME):
+                    self._common_validate_field(
+                        value, InterfacesDef.
+                        interfaces_node_lifecycle_operations,
+                        'interfaces')
+                elif name in (CONFIGURE, CONFIGURE_SHORTNAME):
+                    self._common_validate_field(
+                        value, InterfacesDef.
+                        interfaces_relationship_configure_operations,
+                        'interfaces')
+                elif name in self.type_definition.interfaces.keys():
+                    self._common_validate_field(
+                        value,
+                        self._collect_custom_iface_operations(name),
+                        'interfaces')
+                else:
+                    ExceptionCollector.appendException(
+                        UnknownFieldError(
+                            what='"interfaces" of template "%s"' %
+                            self.name, field=name))
+
+    def _collect_custom_iface_operations(self, name):
+        allowed_operations = []
+        nodetype_iface_def = self.type_definition.interfaces[name]
+        allowed_operations.extend(nodetype_iface_def.keys())
+        if 'type' in nodetype_iface_def:
+            iface_type = nodetype_iface_def['type']
+            if iface_type in self.type_definition.custom_def:
+                iface_type_def = self.type_definition.custom_def[iface_type]
+            else:
+                iface_type_def = self.type_definition.TOSCA_DEF[iface_type]
+            allowed_operations.extend(iface_type_def.keys())
+        allowed_operations = [op for op in allowed_operations if
+                              op not in INTERFACE_DEF_RESERVED_WORDS]
+        return allowed_operations
+
+    def _validate_fields(self, nodetemplate):
+        for name in nodetemplate.keys():
+            if name not in self.SECTIONS and name not in self.SPECIAL_SECTIONS:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Node template "%s"' % self.name,
+                                      field=name))*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/Policy.java b/src/main/java/org/openecomp/sdc/toscaparser/api/Policy.java
new file mode 100644
index 0000000..a59d9d5
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/Policy.java
@@ -0,0 +1,187 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.openecomp.sdc.toscaparser.api.utils.ValidateUtils;
+
+public class Policy extends EntityTemplate {
+	
+
+	private static final String TYPE = "type";
+	private static final String METADATA = "metadata";
+	private static final String DESCRIPTION = "description";
+	private static final String PROPERTIES = "properties";
+	private static final String TARGETS = "targets";
+	private static final String TRIGGERS = "triggers";
+	private static final String SECTIONS[] = {
+			TYPE, METADATA, DESCRIPTION, PROPERTIES, TARGETS, TRIGGERS};
+	
+	LinkedHashMap<String,Object> metaData;
+	ArrayList<Object> targetsList; // *** a list of NodeTemplate OR a list of Group ***
+	String targetsType;
+	ArrayList<Object> triggers;
+	LinkedHashMap<String,Object> properties;
+	
+	public Policy(String _name,
+				  LinkedHashMap<String,Object> _policy,
+//				  ArrayList<NodeTemplate> targetObjects,
+				  ArrayList<Object> targetObjects,
+				  String _targetsType,
+				  LinkedHashMap<String,Object> _customDef) {
+		super(_name,_policy,"policy_type",_customDef);
+
+        metaData = null;
+        if(_policy.get(METADATA) != null) {
+        	metaData = (LinkedHashMap<String,Object>)_policy.get(METADATA);
+        	ValidateUtils.validateMap(metaData);
+        }
+
+        targetsList = targetObjects;
+        targetsType = _targetsType;
+        triggers = _triggers((LinkedHashMap<String,Object>)_policy.get(TRIGGERS));
+        properties = null;
+        if(_policy.get("properties") != null) {
+        	properties = (LinkedHashMap<String,Object>)_policy.get("properties");
+        }
+        _validateKeys();
+	}
+
+	public ArrayList<String> getTargets() {
+		return (ArrayList<String>)entityTpl.get("targets");
+	}
+
+	public ArrayList<String> getDescription() {
+		return (ArrayList<String>)entityTpl.get("description");
+	}
+
+	public ArrayList<String> getmetadata() {
+		return (ArrayList<String>)entityTpl.get("metadata");
+	}
+
+	public String getTargetsType() {
+		return targetsType;
+	}
+ 
+//	public ArrayList<NodeTemplate> getTargetsList() {
+	public ArrayList<Object> getTargetsList() {
+		return targetsList;
+	}
+	
+	// entityTemplate already has a different getProperties...
+	// this is to access the local properties variable
+	public LinkedHashMap<String,Object> getPolicyProperties() {
+		return properties;
+	}
+	
+	private ArrayList<Object> _triggers(LinkedHashMap<String,Object> triggers) {
+		ArrayList<Object> triggerObjs = new ArrayList<>();
+		if(triggers != null) {
+			for(Map.Entry<String,Object> me: triggers.entrySet()) {
+				String tname = me.getKey();
+				LinkedHashMap<String,Object> ttriggerTpl = 
+						(LinkedHashMap<String,Object>)me.getValue();
+				Triggers triggersObj = new Triggers(tname,ttriggerTpl);
+                triggerObjs.add(triggersObj);
+			}
+		}
+		return triggerObjs;
+	}
+
+	private void _validateKeys() {	
+		for(String key: entityTpl.keySet()) {
+			boolean bFound = false;
+			for(int i=0; i<SECTIONS.length; i++) {
+				if(key.equals(SECTIONS[i])) {
+					bFound = true;
+					break;
+				}
+			}
+			if(!bFound) {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                    "UnknownFieldError: Policy \"%s\" contains unknown field \"%s\"",
+	                    name,key));
+			}
+		}
+	}
+
+	@Override
+	public String toString() {
+		return "Policy{" +
+				"metaData=" + metaData +
+				", targetsList=" + targetsList +
+				", targetsType='" + targetsType + '\'' +
+				", triggers=" + triggers +
+				", properties=" + properties +
+				'}';
+	}
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.entity_template import EntityTemplate
+from toscaparser.triggers import Triggers
+from toscaparser.utils import validateutils
+
+
+SECTIONS = (TYPE, METADATA, DESCRIPTION, PROPERTIES, TARGETS, TRIGGERS) = \
+           ('type', 'metadata', 'description',
+            'properties', 'targets', 'triggers')
+
+log = logging.getLogger('tosca')
+
+
+class Policy(EntityTemplate):
+    '''Policies defined in Topology template.'''
+    def __init__(self, name, policy, targets, targets_type, custom_def=None):
+        super(Policy, self).__init__(name,
+                                     policy,
+                                     'policy_type',
+                                     custom_def)
+        self.meta_data = None
+        if self.METADATA in policy:
+            self.meta_data = policy.get(self.METADATA)
+            validateutils.validate_map(self.meta_data)
+        self.targets_list = targets
+        self.targets_type = targets_type
+        self.triggers = self._triggers(policy.get(TRIGGERS))
+        self._validate_keys()
+
+    @property
+    def targets(self):
+        return self.entity_tpl.get('targets')
+
+    @property
+    def description(self):
+        return self.entity_tpl.get('description')
+
+    @property
+    def metadata(self):
+        return self.entity_tpl.get('metadata')
+
+    def get_targets_type(self):
+        return self.targets_type
+
+    def get_targets_list(self):
+        return self.targets_list
+
+    def _triggers(self, triggers):
+        triggerObjs = []
+        if triggers:
+            for name, trigger_tpl in triggers.items():
+                triggersObj = Triggers(name, trigger_tpl)
+                triggerObjs.append(triggersObj)
+        return triggerObjs
+
+    def _validate_keys(self):
+        for key in self.entity_tpl.keys():
+            if key not in SECTIONS:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Policy "%s"' % self.name,
+                                      field=key))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/Property.java b/src/main/java/org/openecomp/sdc/toscaparser/api/Property.java
new file mode 100644
index 0000000..731bc73
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/Property.java
@@ -0,0 +1,177 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.elements.constraints.Constraint;
+import org.openecomp.sdc.toscaparser.api.elements.constraints.Schema;
+import org.openecomp.sdc.toscaparser.api.functions.Function;
+
+public class Property {
+    // TOSCA built-in Property type
+
+	private static final String TYPE = "type";
+	private static final String REQUIRED = "required";
+	private static final String DESCRIPTION = "description";
+	private static final String DEFAULT = "default";
+	private static final String CONSTRAINTS = "constraints";
+	
+	private static final String[] PROPERTY_KEYS = {
+			TYPE, REQUIRED, DESCRIPTION, DEFAULT, CONSTRAINTS};
+
+	private static final String ENTRYTYPE = "type";
+	private static final String ENTRYPROPERTIES = "properties";
+	private static final String[] ENTRY_SCHEMA_KEYS = {
+        ENTRYTYPE, ENTRYPROPERTIES};
+	
+	private String name;
+	private Object value;
+	private Schema schema;
+	private LinkedHashMap<String,Object> customDef;
+
+	public Property(String propname,
+					Object propvalue,
+					LinkedHashMap<String,Object> propschemaDict,
+					LinkedHashMap<String,Object> propcustomDef) {
+		
+        name = propname;
+        value = propvalue;
+        customDef = propcustomDef;
+        schema = new Schema(propname, propschemaDict);
+	}
+	
+	public String getType() {
+		return schema.getType();
+	}
+
+	public boolean isRequired() {
+		return schema.isRequired();
+	}
+	
+	public String getDescription() {
+		return schema.getDescription();
+	}
+
+	public Object getDefault() {
+		return schema.getDefault();
+	}
+
+	public ArrayList<Constraint> getConstraints() {
+		return schema.getConstraints();
+	}
+
+	public LinkedHashMap<String,Object> getEntrySchema() {
+		return schema.getEntrySchema();
+	}
+ 
+
+	public String getName() {
+		return name;
+	}
+
+	public Object getValue() {
+		return value;
+	}
+	
+	// setter
+	public Object setValue(Object vob) {
+		value = vob;
+		return value;
+	}
+	
+	public void validate() {
+		// Validate if not a reference property
+		if(!Function.isFunction(value)) {
+			if(getType().equals(Schema.STRING)) {
+				value = value.toString();
+			}
+			value = DataEntity.validateDatatype(getType(),value,
+                    							 getEntrySchema(),
+                    							 customDef,
+                    							 name);
+			_validateConstraints();
+		}
+	}
+
+	private void _validateConstraints() {
+		if(getConstraints() != null) {
+			for(Constraint constraint: getConstraints()) {
+				constraint.validate(value);
+			}
+		}
+	}
+
+	@Override
+	public String toString() {
+		return "Property{" +
+				"name='" + name + '\'' +
+				", value=" + value +
+				", schema=" + schema +
+				", customDef=" + customDef +
+				'}';
+	}
+}
+
+/*python
+
+class Property(object):
+    '''TOSCA built-in Property type.'''
+
+    PROPERTY_KEYS = (
+        TYPE, REQUIRED, DESCRIPTION, DEFAULT, CONSTRAINTS
+    ) = (
+        'type', 'required', 'description', 'default', 'constraints'
+    )
+
+    ENTRY_SCHEMA_KEYS = (
+        ENTRYTYPE, ENTRYPROPERTIES
+    ) = (
+        'type', 'properties'
+    )
+
+    def __init__(self, property_name, value, schema_dict, custom_def=None):
+        self.name = property_name
+        self.value = value
+        self.custom_def = custom_def
+        self.schema = Schema(property_name, schema_dict)
+
+    @property
+    def type(self):
+        return self.schema.type
+
+    @property
+    def required(self):
+        return self.schema.required
+
+    @property
+    def description(self):
+        return self.schema.description
+
+    @property
+    def default(self):
+        return self.schema.default
+
+    @property
+    def constraints(self):
+        return self.schema.constraints
+
+    @property
+    def entry_schema(self):
+        return self.schema.entry_schema
+
+    def validate(self):
+        '''Validate if not a reference property.'''
+        if not is_function(self.value):
+            if self.type == Schema.STRING:
+                self.value = str(self.value)
+            self.value = DataEntity.validate_datatype(self.type, self.value,
+                                                      self.entry_schema,
+                                                      self.custom_def,
+                                                      self.name)
+            self._validate_constraints()
+
+    def _validate_constraints(self):
+        if self.constraints:
+            for constraint in self.constraints:
+                constraint.validate(self.value)
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/RelationshipTemplate.java b/src/main/java/org/openecomp/sdc/toscaparser/api/RelationshipTemplate.java
new file mode 100644
index 0000000..10d3ad9
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/RelationshipTemplate.java
@@ -0,0 +1,199 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.elements.EntityType;
+import org.openecomp.sdc.toscaparser.api.elements.PropertyDef;
+import org.openecomp.sdc.toscaparser.api.elements.StatefulEntityType;
+
+public class RelationshipTemplate extends EntityTemplate {
+	
+	private static final String DERIVED_FROM = "derived_from";
+	private static final String PROPERTIES = "properties";
+	private static final String REQUIREMENTS = "requirements";
+	private static final String INTERFACES = "interfaces";
+	private static final String CAPABILITIES = "capabilities";
+	private static final String TYPE = "type";
+	@SuppressWarnings("unused")
+	private static final String SECTIONS[] = {
+			DERIVED_FROM, PROPERTIES, REQUIREMENTS, INTERFACES, CAPABILITIES, TYPE};
+	
+	private String name;
+	private NodeTemplate target;
+	private NodeTemplate source;
+	private ArrayList<Property> _properties;
+	
+	public RelationshipTemplate(LinkedHashMap<String,Object> rtrelationshipTemplate,
+								String rtname,
+								LinkedHashMap<String,Object> rtcustomDef,
+								NodeTemplate rttarget,
+								NodeTemplate rtsource) {
+		super(rtname,rtrelationshipTemplate,"relationship_type",rtcustomDef);
+		
+		name = rtname;
+		target = rttarget;
+		source = rtsource;
+		_properties = null;
+	}
+
+	public ArrayList<Property> getPropertiesObjects() {
+		// Return properties objects for this template
+		if(_properties == null) {
+            _properties = _createRelationshipProperties();
+		}
+        return _properties;
+	}
+
+	@SuppressWarnings({ "unchecked", "unused" })
+	public ArrayList<Property> _createRelationshipProperties() {
+		ArrayList<Property> props = new ArrayList<Property> ();
+		LinkedHashMap<String,Object> properties = new LinkedHashMap<String,Object>();
+		LinkedHashMap<String,Object> relationship = (LinkedHashMap<String,Object>)entityTpl.get("relationship");
+		
+		if(relationship == null) {
+			for(Object val: entityTpl.values()) {
+				if(val instanceof LinkedHashMap) {
+					relationship = (LinkedHashMap<String,Object>)((LinkedHashMap<String,Object>)val).get("relationship");
+					break;
+				}
+			}
+		}
+		
+		if(relationship != null) {
+            properties = (LinkedHashMap<String,Object>)((EntityType)typeDefinition).getValue(PROPERTIES,relationship,false);
+		}
+		if(properties == null) {
+			properties = new LinkedHashMap<String,Object>();
+		}
+		if(properties == null) {
+			properties = (LinkedHashMap<String,Object>)entityTpl.get(PROPERTIES);
+		}
+		if(properties == null) {
+			properties = new LinkedHashMap<String,Object>();
+		}
+		
+		if(properties != null) {
+			for(Map.Entry<String,Object> me: properties.entrySet()) {
+				String pname = me.getKey();
+				Object pvalue = me.getValue();
+				LinkedHashMap<String,PropertyDef> propsDef = ((StatefulEntityType)typeDefinition).getPropertiesDef();
+				if(propsDef != null && propsDef.get(pname) != null) {
+					if(properties.get(pname) != null) {
+						pvalue = properties.get(name);
+					}
+					PropertyDef pd = (PropertyDef)propsDef.get(pname);
+					Property prop = new Property(pname,pvalue,pd.getSchema(),customDef);
+					props.add(prop);
+				}
+			}
+		}
+		ArrayList<PropertyDef> pds = ((StatefulEntityType)typeDefinition).getPropertiesDefObjects();
+		for(PropertyDef p: pds) {
+			if(p.getDefault() != null && properties.get(p.getName()) == null) {
+                Property prop = new Property(p.getName(), (LinkedHashMap<String,Object>)p.getDefault(), p.getSchema(), customDef);
+                props.add(prop);
+			}
+		}
+        return props;
+	}
+        
+    public void validate() {
+    	_validateProperties(entityTpl,(StatefulEntityType)typeDefinition);
+    }
+ 
+    // getters/setters
+    public NodeTemplate getTarget() {
+    	return target;
+    }
+    
+    public NodeTemplate getSource() {
+    	return source;
+    }
+    
+    public void setSource(NodeTemplate nt) {
+    	source = nt;
+    }
+    
+    public void setTarget(NodeTemplate nt) {
+    	target = nt;
+    }
+
+	@Override
+	public String toString() {
+		return "RelationshipTemplate{" +
+				"name='" + name + '\'' +
+				", target=" + target.getName() +
+				", source=" + source.getName() +
+				", _properties=" + _properties +
+				'}';
+	}
+
+}
+
+/*python
+
+from toscaparser.entity_template import EntityTemplate
+from toscaparser.properties import Property
+
+SECTIONS = (DERIVED_FROM, PROPERTIES, REQUIREMENTS,
+            INTERFACES, CAPABILITIES, TYPE) = \
+           ('derived_from', 'properties', 'requirements', 'interfaces',
+            'capabilities', 'type')
+
+log = logging.getLogger('tosca')
+
+
+class RelationshipTemplate(EntityTemplate):
+    '''Relationship template.'''
+    def __init__(self, relationship_template, name, custom_def=None,
+                 target=None, source=None):
+        super(RelationshipTemplate, self).__init__(name,
+                                                   relationship_template,
+                                                   'relationship_type',
+                                                   custom_def)
+        self.name = name.lower()
+        self.target = target
+        self.source = source
+
+    def get_properties_objects(self):
+        '''Return properties objects for this template.'''
+        if self._properties is None:
+            self._properties = self._create_relationship_properties()
+        return self._properties
+
+    def _create_relationship_properties(self):
+        props = []
+        properties = {}
+        relationship = self.entity_tpl.get('relationship')
+
+        if not relationship:
+            for value in self.entity_tpl.values():
+                if isinstance(value, dict):
+                    relationship = value.get('relationship')
+                    break
+
+        if relationship:
+            properties = self.type_definition.get_value(self.PROPERTIES,
+                                                        relationship) or {}
+        if not properties:
+            properties = self.entity_tpl.get(self.PROPERTIES) or {}
+
+        if properties:
+            for name, value in properties.items():
+                props_def = self.type_definition.get_properties_def()
+                if props_def and name in props_def:
+                    if name in properties.keys():
+                        value = properties.get(name)
+                    prop = Property(name, value,
+                                    props_def[name].schema, self.custom_def)
+                    props.append(prop)
+        for p in self.type_definition.get_properties_def_objects():
+            if p.default is not None and p.name not in properties.keys():
+                prop = Property(p.name, p.default, p.schema, self.custom_def)
+                props.append(prop)
+        return props
+
+    def validate(self):
+        self._validate_properties(self.entity_tpl, self.type_definition)*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/Repository.java b/src/main/java/org/openecomp/sdc/toscaparser/api/Repository.java
new file mode 100644
index 0000000..92a90af
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/Repository.java
@@ -0,0 +1,117 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.openecomp.sdc.toscaparser.api.utils.UrlUtils;
+
+public class Repository {
+	
+	private static final String DESCRIPTION = "description";
+	private static final String URL = "url";
+	private static final String CREDENTIAL = "credential";
+	private static final String SECTIONS[] ={DESCRIPTION, URL, CREDENTIAL};
+	
+	private String name;
+	private Object reposit;
+	private String url;
+	
+	@SuppressWarnings("unchecked")
+	public Repository(String repName,Object repValue) {
+		name = repName;
+		reposit = repValue;
+		if(reposit instanceof LinkedHashMap) {
+			url = (String)((LinkedHashMap<String,Object>)reposit).get("url");
+            if(url == null) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "MissingRequiredFieldError: Repository \"%s\" is missing required field \"url\"",
+                    name));
+            }
+		}
+        loadAndValidate(name,reposit);
+	}
+
+	@SuppressWarnings("unchecked")
+	private void loadAndValidate(String val,Object repositDef) {
+		String keyname = val;
+		if(repositDef instanceof LinkedHashMap) {
+			for(String key: ((LinkedHashMap<String,Object>)reposit).keySet()) {
+				boolean bFound = false;
+				for(String sect: SECTIONS) {
+					if(key.equals(sect)) {
+						bFound = true;
+						break;
+					}
+				}
+				if(!bFound) {
+                    ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "UnknownFieldError: repositories \"%s\" contains unknown field \"%s\"",
+                        keyname,key));
+				}
+			}
+			
+			String repositUrl = (String)((LinkedHashMap<String,Object>)repositDef).get("url");
+	        if(repositUrl != null) {
+	            boolean urlVal = UrlUtils.validateUrl(repositUrl);
+	            if(!urlVal) {
+	                ThreadLocalsHolder.getCollector().appendException(String.format(
+	                    "URLException: repsositories \"%s\" Invalid Url",keyname));
+	            }
+	        }
+		}
+	}
+
+	@Override
+	public String toString() {
+		return "Repository{" +
+				"name='" + name + '\'' +
+				", reposit=" + reposit +
+				", url='" + url + '\'' +
+				'}';
+	}
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import MissingRequiredFieldError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.common.exception import URLException
+from toscaparser.utils.gettextutils import _
+import org.openecomp.sdc.toscaparser.api.utils.urlutils
+
+SECTIONS = (DESCRIPTION, URL, CREDENTIAL) = \
+           ('description', 'url', 'credential')
+
+
+class Repository(object):
+    def __init__(self, repositories, values):
+        self.name = repositories
+        self.reposit = values
+        if isinstance(self.reposit, dict):
+            if 'url' not in self.reposit.keys():
+                ExceptionCollector.appendException(
+                    MissingRequiredFieldError(what=_('Repository "%s"')
+                                              % self.name, required='url'))
+            self.url = self.reposit['url']
+        self.load_and_validate(self.name, self.reposit)
+
+    def load_and_validate(self, val, reposit_def):
+        self.keyname = val
+        if isinstance(reposit_def, dict):
+            for key in reposit_def.keys():
+                if key not in SECTIONS:
+                    ExceptionCollector.appendException(
+                        UnknownFieldError(what=_('repositories "%s"')
+                                          % self.keyname, field=key))
+
+            if URL in reposit_def.keys():
+                reposit_url = reposit_def.get(URL)
+                url_val = toscaparser.utils.urlutils.UrlUtils.\
+                    validate_url(reposit_url)
+                if url_val is not True:
+                    ExceptionCollector.appendException(
+                        URLException(what=_('repsositories "%s" Invalid Url')
+                                     % self.keyname))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/SubstitutionMappings.java b/src/main/java/org/openecomp/sdc/toscaparser/api/SubstitutionMappings.java
new file mode 100644
index 0000000..b9c2238
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/SubstitutionMappings.java
@@ -0,0 +1,520 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.NodeType;
+import org.openecomp.sdc.toscaparser.api.elements.PropertyDef;
+import org.openecomp.sdc.toscaparser.api.parameters.Input;
+import org.openecomp.sdc.toscaparser.api.parameters.Output;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+
+public class SubstitutionMappings {
+    // SubstitutionMappings class declaration
+
+    // SubstitutionMappings exports the topology template as an
+    // implementation of a Node type.
+
+	private static final String NODE_TYPE = "node_type";
+	private static final String REQUIREMENTS = "requirements";
+	private static final String CAPABILITIES = "capabilities";
+
+	private static final String SECTIONS[] = {NODE_TYPE, REQUIREMENTS, CAPABILITIES};
+
+	private static final String OPTIONAL_OUTPUTS[] = {"tosca_id", "tosca_name", "state"};
+	
+	private LinkedHashMap<String,Object> subMappingDef;
+	private ArrayList<NodeTemplate> nodetemplates;
+	private ArrayList<Input> inputs;
+	private ArrayList<Output> outputs;
+	private ArrayList<Group> groups;
+	private NodeTemplate subMappedNodeTemplate;
+	private LinkedHashMap<String,Object> customDefs;
+	private LinkedHashMap<String,Object> _capabilities;
+	private LinkedHashMap<String,Object> _requirements;
+	
+	public SubstitutionMappings(LinkedHashMap<String,Object> smsubMappingDef,
+								ArrayList<NodeTemplate> smnodetemplates,
+								ArrayList<Input> sminputs,
+								ArrayList<Output> smoutputs,
+								ArrayList<Group> smgroups,
+								NodeTemplate smsubMappedNodeTemplate,
+								LinkedHashMap<String,Object> smcustomDefs) {
+		
+        subMappingDef = smsubMappingDef;
+        nodetemplates = smnodetemplates;
+        inputs = sminputs != null ? sminputs : new ArrayList<Input>();
+        outputs = smoutputs != null ? smoutputs : new ArrayList<Output>();
+        groups = smgroups != null ? smgroups : new ArrayList<Group>();
+        subMappedNodeTemplate = smsubMappedNodeTemplate;
+        customDefs = smcustomDefs != null ? smcustomDefs : new LinkedHashMap<String,Object>();
+        _validate();
+
+        _capabilities = null;
+        _requirements = null;
+	}
+
+	public String getType() {
+		if(subMappingDef != null) {
+			return (String)subMappingDef.get(NODE_TYPE);
+		}
+		return null;
+	}
+	
+	public ArrayList<NodeTemplate> getNodeTemplates() {
+		return nodetemplates;
+	}
+
+	/*
+    @classmethod
+    def get_node_type(cls, sub_mapping_def):
+        if isinstance(sub_mapping_def, dict):
+            return sub_mapping_def.get(cls.NODE_TYPE)
+	*/
+	
+	public static String stGetNodeType(LinkedHashMap<String,Object> _subMappingDef) {
+		if(_subMappingDef instanceof LinkedHashMap) {
+			return (String)_subMappingDef.get(NODE_TYPE);
+		}
+		return null;
+	}
+
+	public String getNodeType() {
+        return (String)subMappingDef.get(NODE_TYPE);
+	}
+	
+	public ArrayList<Input> getInputs() {
+		return inputs;
+	}
+	
+	public ArrayList<Group> getGroups() {
+		return groups;
+	}
+	
+	public LinkedHashMap<String,Object> getCapabilities() {
+		return (LinkedHashMap<String,Object>)subMappingDef.get(CAPABILITIES);
+	}
+
+	public LinkedHashMap<String,Object> getRequirements() {
+		return (LinkedHashMap<String,Object>)subMappingDef.get(REQUIREMENTS);
+	}
+
+	public NodeType getNodeDefinition() {
+		return new NodeType(getNodeType(), customDefs);
+	}
+
+	private void _validate() {
+        // Basic validation
+        _validateKeys();
+        _validateType();
+
+        // SubstitutionMapping class syntax validation
+        _validateInputs();
+        _validateCapabilities();
+        _validateRequirements();
+        _validateOutputs();
+	}
+	
+	private void _validateKeys() {
+		// validate the keys of substitution mappings
+		for(String key: subMappingDef.keySet()) {
+			boolean bFound = false;
+			for(String s: SECTIONS) {
+				if(s.equals(key)) {
+					bFound = true;
+					break;
+				}
+			}
+			if(!bFound) {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "UnknownFieldError: SubstitutionMappings contain unknown field \"%s\"",
+	                key));
+			}
+		}
+	}
+
+	private void _validateType() {
+        // validate the node_type of substitution mappings
+        String nodeType = (String)subMappingDef.get(NODE_TYPE);
+        if(nodeType == null) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                "MissingRequiredFieldError: SubstitutionMappings used in topology_template is missing required field \"%s\"",
+                NODE_TYPE));
+        }
+        Object nodeTypeDef = customDefs.get(nodeType);
+        if(nodeTypeDef == null) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                "InvalidNodeTypeError: \"%s\" is invalid",nodeType));
+        }
+	}
+
+	private void _validateInputs() {
+        // validate the inputs of substitution mappings.
+
+        // The inputs defined by the topology template have to match the
+        // properties of the node type or the substituted node. If there are
+        // more inputs than the substituted node has properties, default values
+        //must be defined for those inputs.
+		
+		HashSet<String> allInputs = new HashSet<>();
+		for(Input inp: inputs) {
+			allInputs.add(inp.getName());
+		}
+		HashSet<String> requiredProperties = new HashSet<>();
+		for(PropertyDef pd: getNodeDefinition().getPropertiesDefObjects()) {
+			if(pd.isRequired() && pd.getDefault() == null) {
+				requiredProperties.add(pd.getName());
+			}
+		}
+        // Must provide inputs for required properties of node type.
+        for(String property: requiredProperties) {
+            // Check property which is 'required' and has no 'default' value
+            if(!allInputs.contains(property)) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "MissingRequiredInputError: SubstitutionMappings with node_type \"%s\" is missing required input \"%s\"",
+                    getNodeType(),property));
+            }
+        }
+        // If the optional properties of node type need to be customized by
+        // substituted node, it also is necessary to define inputs for them,
+        // otherwise they are not mandatory to be defined.
+         HashSet<String> customizedParameters = new HashSet<>();
+         if(subMappedNodeTemplate != null) {
+        	 customizedParameters.addAll(subMappedNodeTemplate.getProperties().keySet());
+         }
+         HashSet<String> allProperties = new HashSet<String>(
+        		 getNodeDefinition().getPropertiesDef().keySet());
+         HashSet<String> diffset = customizedParameters;
+         diffset.removeAll(allInputs);
+         for(String parameter: diffset) {
+        	 if(allProperties.contains(parameter)) {
+                 ThreadLocalsHolder.getCollector().appendException(String.format(
+                     "MissingRequiredInputError: SubstitutionMappings with node_type \"%s\" is missing required input \"%s\"",
+                     getNodeType(),parameter));
+        	 }
+         }
+	    // Additional inputs are not in the properties of node type must
+	    // provide default values. Currently the scenario may not happen
+	    // because of parameters validation in nodetemplate, here is a
+	    // guarantee.
+	    for(Input inp: inputs) {
+	    	diffset = allInputs;
+	    	diffset.removeAll(allProperties);
+	    	if(diffset.contains(inp.getName()) && inp.getDefault() == null) {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                     "MissingRequiredInputError: SubstitutionMappings with node_type \"%s\" is missing rquired input \"%s\"",
+	                     getNodeType(),inp.getName()));
+	    	}
+	    }
+	}
+	
+	private void _validateCapabilities() {
+        // validate the capabilities of substitution mappings
+
+        // The capabilities must be in node template which be mapped.
+		LinkedHashMap<String,Object> tplsCapabilities = 
+				(LinkedHashMap<String,Object>)subMappingDef.get(CAPABILITIES);
+		LinkedHashMap<String,Capability> nodeCapabilities = null;
+		if(subMappedNodeTemplate != null) {
+			nodeCapabilities = subMappedNodeTemplate.getCapabilities();
+		}
+		if(nodeCapabilities != null) {
+			for(String cap: nodeCapabilities.keySet()) {
+				if(tplsCapabilities != null && tplsCapabilities.get(cap) == null) {
+	                ; //pass
+	                // ExceptionCollector.appendException(
+	                //    UnknownFieldError(what='SubstitutionMappings',
+	                //                      field=cap))
+				}
+			}
+		}
+	}
+ 
+	private void _validateRequirements() {
+        // validate the requirements of substitution mappings
+		//*****************************************************
+		//TO-DO - Different from Python code!! one is a bug...
+		//*****************************************************
+        // The requirements must be in node template which be mapped.
+		LinkedHashMap<String,Object> tplsRequirements = 
+				(LinkedHashMap<String,Object>)subMappingDef.get(REQUIREMENTS);
+		ArrayList<Object> nodeRequirements = null;
+		if(subMappedNodeTemplate != null) {
+			nodeRequirements = subMappedNodeTemplate.getRequirements();
+		}
+		if(nodeRequirements != null) {
+			for(Object ro: nodeRequirements) {
+				ArrayList<String> al = new ArrayList<String>(
+						((LinkedHashMap<String,Object>)ro).keySet());
+				String cap = al.get(0);
+				if(tplsRequirements != null && tplsRequirements.get(cap) == null) {
+	                ; //pass
+	                // ExceptionCollector.appendException(
+	                //    UnknownFieldError(what='SubstitutionMappings',
+	                //                      field=cap))
+				}
+			}
+		}
+	}
+	
+	private void _validateOutputs() {
+        // validate the outputs of substitution mappings.
+
+        // The outputs defined by the topology template have to match the
+        // attributes of the node type or the substituted node template,
+        // and the observable attributes of the substituted node template
+        // have to be defined as attributes of the node type or outputs in
+        // the topology template.
+
+        // The outputs defined by the topology template have to match the
+        // attributes of the node type according to the specification, but
+        // it's reasonable that there are more inputs than the node type
+        // has properties, the specification will be amended?
+		
+        for(Output output: outputs) {
+        	Object ado = getNodeDefinition().getAttributesDef();
+        	if(ado != null && ((LinkedHashMap<String,Object>)ado).get(output.getName()) == null) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "UnknownOutputError: Unknown output \"%s\" in SubstitutionMappings with node_type \"%s\"",
+                    output.getName(),getNodeType()));
+        	}
+        }
+ 	}
+
+	@Override
+	public String toString() {
+		return "SubstitutionMappings{" +
+//				"subMappingDef=" + subMappingDef +
+//				", nodetemplates=" + nodetemplates +
+//				", inputs=" + inputs +
+//				", outputs=" + outputs +
+//				", groups=" + groups +
+				", subMappedNodeTemplate=" + (subMappedNodeTemplate==null?"":subMappedNodeTemplate.getName()) +
+//				", customDefs=" + customDefs +
+//				", _capabilities=" + _capabilities +
+//				", _requirements=" + _requirements +
+				'}';
+	}
+
+	@Deprecated
+	public String toLimitedString() {
+		return "SubstitutionMappings{" +
+				"subMappingDef=" + subMappingDef +
+				", nodetemplates=" + nodetemplates +
+				", inputs=" + inputs +
+				", outputs=" + outputs +
+				", groups=" + groups +
+				", subMappedNodeTemplate=" + (subMappedNodeTemplate==null?"":subMappedNodeTemplate.getName()) +
+				", customDefs=" + customDefs +
+				", _capabilities=" + _capabilities +
+				", _requirements=" + _requirements +
+				'}';
+	}
+}
+
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidNodeTypeError
+from toscaparser.common.exception import MissingDefaultValueError
+from toscaparser.common.exception import MissingRequiredFieldError
+from toscaparser.common.exception import MissingRequiredInputError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.common.exception import UnknownOutputError
+from toscaparser.elements.nodetype import NodeType
+from toscaparser.utils.gettextutils import _
+
+log = logging.getLogger('tosca')
+
+
+class SubstitutionMappings(object):
+    '''SubstitutionMappings class declaration
+
+    SubstitutionMappings exports the topology template as an
+    implementation of a Node type.
+    '''
+
+    SECTIONS = (NODE_TYPE, REQUIREMENTS, CAPABILITIES) = \
+               ('node_type', 'requirements', 'capabilities')
+
+    OPTIONAL_OUTPUTS = ['tosca_id', 'tosca_name', 'state']
+
+    def __init__(self, sub_mapping_def, nodetemplates, inputs, outputs,
+                 sub_mapped_node_template, custom_defs):
+        self.nodetemplates = nodetemplates
+        self.sub_mapping_def = sub_mapping_def
+        self.inputs = inputs or []
+        self.outputs = outputs or []
+        self.sub_mapped_node_template = sub_mapped_node_template
+        self.custom_defs = custom_defs or {}
+        self._validate()
+
+        self._capabilities = None
+        self._requirements = None
+
+    @property
+    def type(self):
+        if self.sub_mapping_def:
+            return self.sub_mapping_def.get(self.NODE_TYPE)
+
+    @classmethod
+    def get_node_type(cls, sub_mapping_def):
+        if isinstance(sub_mapping_def, dict):
+            return sub_mapping_def.get(cls.NODE_TYPE)
+
+    @property
+    def node_type(self):
+        return self.sub_mapping_def.get(self.NODE_TYPE)
+
+    @property
+    def capabilities(self):
+        return self.sub_mapping_def.get(self.CAPABILITIES)
+
+    @property
+    def requirements(self):
+        return self.sub_mapping_def.get(self.REQUIREMENTS)
+
+    @property
+    def node_definition(self):
+        return NodeType(self.node_type, self.custom_defs)
+
+    def _validate(self):
+        # Basic validation
+        self._validate_keys()
+        self._validate_type()
+
+        # SubstitutionMapping class syntax validation
+        self._validate_inputs()
+        self._validate_capabilities()
+        self._validate_requirements()
+        self._validate_outputs()
+
+    def _validate_keys(self):
+        """validate the keys of substitution mappings."""
+        for key in self.sub_mapping_def.keys():
+            if key not in self.SECTIONS:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what=_('SubstitutionMappings'),
+                                      field=key))
+
+    def _validate_type(self):
+        """validate the node_type of substitution mappings."""
+        node_type = self.sub_mapping_def.get(self.NODE_TYPE)
+        if not node_type:
+            ExceptionCollector.appendException(
+                MissingRequiredFieldError(
+                    what=_('SubstitutionMappings used in topology_template'),
+                    required=self.NODE_TYPE))
+
+        node_type_def = self.custom_defs.get(node_type)
+        if not node_type_def:
+            ExceptionCollector.appendException(
+                InvalidNodeTypeError(what=node_type))
+
+    def _validate_inputs(self):
+        """validate the inputs of substitution mappings.
+
+        The inputs defined by the topology template have to match the
+        properties of the node type or the substituted node. If there are
+        more inputs than the substituted node has properties, default values
+        must be defined for those inputs.
+        """
+
+        all_inputs = set([input.name for input in self.inputs])
+        required_properties = set([p.name for p in
+                                   self.node_definition.
+                                   get_properties_def_objects()
+                                   if p.required and p.default is None])
+        # Must provide inputs for required properties of node type.
+        for property in required_properties:
+            # Check property which is 'required' and has no 'default' value
+            if property not in all_inputs:
+                ExceptionCollector.appendException(
+                    MissingRequiredInputError(
+                        what=_('SubstitutionMappings with node_type ')
+                        + self.node_type,
+                        input_name=property))
+
+        # If the optional properties of node type need to be customized by
+        # substituted node, it also is necessary to define inputs for them,
+        # otherwise they are not mandatory to be defined.
+        customized_parameters = set(self.sub_mapped_node_template
+                                    .get_properties().keys()
+                                    if self.sub_mapped_node_template else [])
+        all_properties = set(self.node_definition.get_properties_def())
+        for parameter in customized_parameters - all_inputs:
+            if parameter in all_properties:
+                ExceptionCollector.appendException(
+                    MissingRequiredInputError(
+                        what=_('SubstitutionMappings with node_type ')
+                        + self.node_type,
+                        input_name=parameter))
+
+        # Additional inputs are not in the properties of node type must
+        # provide default values. Currently the scenario may not happen
+        # because of parameters validation in nodetemplate, here is a
+        # guarantee.
+        for input in self.inputs:
+            if input.name in all_inputs - all_properties \
+               and input.default is None:
+                ExceptionCollector.appendException(
+                    MissingDefaultValueError(
+                        what=_('SubstitutionMappings with node_type ')
+                        + self.node_type,
+                        input_name=input.name))
+
+    def _validate_capabilities(self):
+        """validate the capabilities of substitution mappings."""
+
+        # The capabilites must be in node template wchich be mapped.
+        tpls_capabilities = self.sub_mapping_def.get(self.CAPABILITIES)
+        node_capabiliteys = self.sub_mapped_node_template.get_capabilities() \
+            if self.sub_mapped_node_template else None
+        for cap in node_capabiliteys.keys() if node_capabiliteys else []:
+            if (tpls_capabilities and
+                    cap not in list(tpls_capabilities.keys())):
+                pass
+                # ExceptionCollector.appendException(
+                #    UnknownFieldError(what='SubstitutionMappings',
+                #                      field=cap))
+
+    def _validate_requirements(self):
+        """validate the requirements of substitution mappings."""
+
+        # The requirements must be in node template wchich be mapped.
+        tpls_requirements = self.sub_mapping_def.get(self.REQUIREMENTS)
+        node_requirements = self.sub_mapped_node_template.requirements \
+            if self.sub_mapped_node_template else None
+        for req in node_requirements if node_requirements else []:
+            if (tpls_requirements and
+                    req not in list(tpls_requirements.keys())):
+                pass
+                # ExceptionCollector.appendException(
+                #    UnknownFieldError(what='SubstitutionMappings',
+                #                      field=req))
+
+    def _validate_outputs(self):
+        """validate the outputs of substitution mappings.
+
+        The outputs defined by the topology template have to match the
+        attributes of the node type or the substituted node template,
+        and the observable attributes of the substituted node template
+        have to be defined as attributes of the node type or outputs in
+        the topology template.
+        """
+
+        # The outputs defined by the topology template have to match the
+        # attributes of the node type according to the specification, but
+        # it's reasonable that there are more inputs than the node type
+        # has properties, the specification will be amended?
+        for output in self.outputs:
+            if output.name not in self.node_definition.get_attributes_def():
+                ExceptionCollector.appendException(
+                    UnknownOutputError(
+                        where=_('SubstitutionMappings with node_type ')
+                        + self.node_type,
+                        output_name=output.name))*/		
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/TopologyTemplate.java b/src/main/java/org/openecomp/sdc/toscaparser/api/TopologyTemplate.java
new file mode 100644
index 0000000..25f118b
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/TopologyTemplate.java
@@ -0,0 +1,857 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.InterfacesDef;
+import org.openecomp.sdc.toscaparser.api.elements.NodeType;
+import org.openecomp.sdc.toscaparser.api.elements.RelationshipType;
+import org.openecomp.sdc.toscaparser.api.functions.Function;
+import org.openecomp.sdc.toscaparser.api.functions.GetAttribute;
+import org.openecomp.sdc.toscaparser.api.functions.GetInput;
+import org.openecomp.sdc.toscaparser.api.parameters.Input;
+import org.openecomp.sdc.toscaparser.api.parameters.Output;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class TopologyTemplate {
+
+	private static final String DESCRIPTION = "description";
+	private static final String INPUTS = "inputs";
+	private static final String NODE_TEMPLATES = "node_templates";
+	private static final String RELATIONSHIP_TEMPLATES = "relationship_templates";
+	private static final String OUTPUTS = "outputs";
+	private static final String GROUPS = "groups";
+	private static final String SUBSTITUTION_MAPPINGS = "substitution_mappings";
+	private static final String POLICIES = "policies";
+	private static final String METADATA = "metadata";
+	
+	private static String SECTIONS[] = {
+				DESCRIPTION, INPUTS, NODE_TEMPLATES, RELATIONSHIP_TEMPLATES, 
+				OUTPUTS, GROUPS,  SUBSTITUTION_MAPPINGS, POLICIES, METADATA
+			};
+
+    private LinkedHashMap<String,Object> tpl;
+	LinkedHashMap<String,Object> metaData;
+    private ArrayList<Input> inputs;
+    private ArrayList<Output> outputs;
+    private ArrayList<RelationshipTemplate> relationshipTemplates;
+    private ArrayList<NodeTemplate> nodeTemplates;
+	private LinkedHashMap<String,Object> customDefs;
+	private LinkedHashMap<String,Object> relTypes;//TYPE
+    private NodeTemplate subMappedNodeTemplate;
+    private ArrayList<Group> groups;
+    private ArrayList<Policy> policies;
+    private LinkedHashMap<String,Object> parsedParams = null;//TYPE
+    private String description;
+    private ToscaGraph graph;
+    private SubstitutionMappings substitutionMappings;
+	
+	public TopologyTemplate(
+			LinkedHashMap<String,Object> _template, 
+			LinkedHashMap<String,Object> _customDefs,
+			LinkedHashMap<String,Object> _relTypes,//TYPE
+            LinkedHashMap<String, Object> _parsedParams,
+            NodeTemplate  _subMappedNodeTemplate) {
+
+		tpl = _template;
+		if(tpl != null) {
+			subMappedNodeTemplate = _subMappedNodeTemplate;
+			metaData = _metaData();
+			customDefs = _customDefs;
+			relTypes = _relTypes;
+			parsedParams = _parsedParams;
+			_validateField();
+			description = _tplDescription();
+			inputs = _inputs();
+	        relationshipTemplates =_relationshipTemplates();
+	        nodeTemplates = _nodeTemplates();
+	        outputs = _outputs();
+	        if(nodeTemplates != null) {
+	        	graph = new ToscaGraph(nodeTemplates);
+	        }
+	        groups = _groups();
+	        policies = _policies();
+	        _processIntrinsicFunctions();
+            substitutionMappings = _substitutionMappings();
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	private ArrayList<Input> _inputs() {
+		//DumpUtils.dumpYaml(customDefs,0);
+		ArrayList<Input> alInputs = new ArrayList<>();
+		for(String name: _tplInputs().keySet()) {
+			Object attrs = _tplInputs().get(name);
+			Input input = new Input(name,(LinkedHashMap<String,Object>)attrs,customDefs);
+            if(parsedParams != null && parsedParams.get(name) != null) {
+            	input.validate(parsedParams.get(name));
+            }
+            else {
+                Object _default = input.getDefault();
+                if(_default != null) {
+                    input.validate(_default);
+                }
+            }
+            if((parsedParams != null && parsedParams.get(input.getName()) == null || parsedParams == null)
+            		 && input.isRequired() && input.getDefault() == null) {
+            	System.out.format("Log warning: The required parameter \"%s\" is not provided\n",input.getName());
+            }
+            alInputs.add(input);
+		}
+        return alInputs;
+		
+	}
+
+	private LinkedHashMap<String,Object> _metaData() {
+        if(tpl.get(METADATA) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(METADATA);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+	
+	}
+
+	private ArrayList<NodeTemplate> _nodeTemplates() {
+		ArrayList<NodeTemplate> alNodeTemplates = new ArrayList<>();
+		LinkedHashMap<String,Object> tpls = _tplNodeTemplates();
+		if(tpls != null) {
+			for(String name: tpls.keySet()) {
+				NodeTemplate tpl = new NodeTemplate(name,
+													tpls,
+													customDefs,
+													relationshipTemplates,
+													relTypes);
+				if(tpl.getTypeDefinition() != null) {
+					boolean b = NodeType.TOSCA_DEF.get(tpl.getType()) != null;
+					if(b || (tpl.getCustomDef() != null && !tpl.getCustomDef().isEmpty())) {
+						tpl.validate();
+						alNodeTemplates.add(tpl);
+					}
+				}
+			}
+		}
+		return alNodeTemplates;
+	}
+	
+	@SuppressWarnings("unchecked")
+	private ArrayList<RelationshipTemplate> _relationshipTemplates() {
+		ArrayList<RelationshipTemplate> alRelationshipTemplates = new ArrayList<>();
+		LinkedHashMap<String,Object> tpls = _tplRelationshipTemplates();
+		if(tpls != null) {
+			for(String name: tpls.keySet()) {
+				RelationshipTemplate tpl = new RelationshipTemplate(
+						(LinkedHashMap<String,Object>)tpls.get(name),name,customDefs,null,null);
+						
+				alRelationshipTemplates.add(tpl);
+			}
+		}
+		return alRelationshipTemplates;
+	}
+	
+	private ArrayList<Output> _outputs() {
+		ArrayList<Output> alOutputs = new ArrayList<>();
+		for(Map.Entry<String,Object> me: _tplOutputs().entrySet()) {
+			String oname = me.getKey();
+			LinkedHashMap<String,Object> oattrs = (LinkedHashMap<String,Object>)me.getValue(); 
+			Output o = new Output(oname,oattrs);
+			o.validate();
+			alOutputs.add(o);
+		}
+		return alOutputs;
+	}
+	
+	private SubstitutionMappings _substitutionMappings() {
+		LinkedHashMap<String,Object> tplSubstitutionMapping = (LinkedHashMap<String,Object>) _tplSubstitutionMappings();
+		
+		//*** the commenting-out below and the weaker condition are in the Python source
+		// #if tpl_substitution_mapping and self.sub_mapped_node_template:
+		if(tplSubstitutionMapping != null && tplSubstitutionMapping.size() > 0) {
+			return new SubstitutionMappings(tplSubstitutionMapping,
+					                    nodeTemplates,
+					                    inputs,
+					                    outputs,
+					                    groups,
+					                    subMappedNodeTemplate,
+					                    customDefs);
+		}
+		return null;
+		
+	}
+	
+	@SuppressWarnings("unchecked")
+	private ArrayList<Policy> _policies() {
+		ArrayList<Policy> alPolicies = new ArrayList<>();
+		for(Object po: _tplPolicies()) {
+			LinkedHashMap<String,Object> policy = (LinkedHashMap<String,Object>)po;
+			for(Map.Entry<String,Object> me: policy.entrySet()) {
+				String policyName = me.getKey();
+				LinkedHashMap<String,Object> policyTpl = (LinkedHashMap<String,Object>)me.getValue();
+				ArrayList<String> targetList = (ArrayList<String>)policyTpl.get("targets");
+				//ArrayList<Object> targetObjects = new ArrayList<>();
+				ArrayList<NodeTemplate> targetNodes = new ArrayList<>();
+				ArrayList<Object> targetObjects = new ArrayList<>();
+				ArrayList<Group> targetGroups = new ArrayList<>();
+				String targetsType = "groups"; 
+				if(targetList != null && targetList.size() >= 1) {
+                    targetGroups = _getPolicyGroups(targetList);
+                    if(targetGroups == null) {
+                    	targetsType = "node_templates";
+                        targetNodes = _getGroupMembers(targetList);
+                        for(NodeTemplate nt: targetNodes) {
+                        	targetObjects.add(nt);
+                        }
+                    }
+                    else {
+                    	for(Group gr: targetGroups) {
+                    		targetObjects.add(gr);
+                    	}
+                    }
+				}
+                Policy policyObj = new Policy(policyName, 
+                							  policyTpl,
+		                                      targetObjects, 
+		                                      targetsType,
+		                                      customDefs);
+                alPolicies.add(policyObj);
+			}
+		}
+        return alPolicies;
+	}
+	
+	private ArrayList<Group> _groups() {
+		ArrayList<Group> groups = new ArrayList<>();
+		ArrayList<NodeTemplate> memberNodes  = null;
+		for(Map.Entry<String,Object> me: _tplGroups().entrySet()) {
+			String groupName = me.getKey();
+			LinkedHashMap<String,Object> groupTpl = (LinkedHashMap<String,Object>)me.getValue();
+			ArrayList<String> memberNames = (ArrayList<String>)groupTpl.get("members");
+			if(memberNames != null) {
+                DataEntity.validateDatatype("list", memberNames,null,null,null);
+				if(memberNames.size() < 1 || 
+				       (new HashSet<String>(memberNames)).size() != memberNames.size()) {
+                    ThreadLocalsHolder.getCollector().appendWarning(String.format(
+                            "InvalidGroupTargetException: Member nodes \"%s\" should be >= 1 and not repeated",
+                            memberNames.toString()));
+				}
+				else {
+					memberNodes = _getGroupMembers(memberNames);
+				}
+			}
+            Group group = new Group(groupName,
+            						groupTpl,
+            						memberNodes,
+            						customDefs);
+            groups.add(group);
+		}
+		return groups;
+	}
+	
+	private ArrayList<NodeTemplate> _getGroupMembers(ArrayList<String> memberNames) {
+		ArrayList<NodeTemplate> memberNodes = new ArrayList<>();
+		_validateGroupMembers(memberNames);
+		for(String member: memberNames) {
+			for(NodeTemplate node: nodeTemplates) {
+				if(member.equals(node.getName())) {
+					memberNodes.add(node);
+				}
+			}
+		}
+		return memberNodes;
+	}
+	
+	private ArrayList<Group> _getPolicyGroups(ArrayList<String> memberNames) {
+		ArrayList<Group> memberGroups = new ArrayList<>();
+		for(String member: memberNames) {
+			for(Group group: groups) {
+				if(member.equals(group.getName())) {
+					memberGroups.add(group);
+				}
+			}
+		}
+		return memberGroups;
+	}
+	
+	private void _validateGroupMembers(ArrayList<String> members) {
+		ArrayList<String> nodeNames = new ArrayList<>();
+		for(NodeTemplate node: nodeTemplates) {
+			nodeNames.add(node.getName());
+		}
+		for(String member: members) {
+			if(!nodeNames.contains(member)) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "InvalidGroupTargetException: Target member \"%s\" is not found in \"nodeTemplates\"",member));
+			}
+		}
+	}
+	
+	// topology template can act like node template
+	// it is exposed by substitution_mappings.
+
+	public String nodetype() {
+		return substitutionMappings.getNodeType();
+	}
+	
+	public LinkedHashMap<String,Object> capabilities() {
+		return substitutionMappings.getCapabilities();
+	}
+	
+	public LinkedHashMap<String,Object> requirements() {
+		return substitutionMappings.getRequirements();
+	}
+
+	private String _tplDescription() {
+        return (String)tpl.get(DESCRIPTION);
+        //if description:
+        //	return description.rstrip()
+	}
+
+	@SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _tplInputs() {
+        if(tpl.get(INPUTS) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(INPUTS);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _tplNodeTemplates() {
+        return (LinkedHashMap<String,Object>)tpl.get(NODE_TEMPLATES);
+    }
+
+    @SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _tplRelationshipTemplates() {
+        if(tpl.get(RELATIONSHIP_TEMPLATES) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(RELATIONSHIP_TEMPLATES);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+ 	private LinkedHashMap<String,Object> _tplOutputs() {
+         if(tpl.get(OUTPUTS) != null) {
+         	return (LinkedHashMap<String,Object>)tpl.get(OUTPUTS);
+         }
+         else {
+         	return new LinkedHashMap<String,Object>();
+         }
+     }
+
+    @SuppressWarnings("unchecked")
+    private LinkedHashMap<String,Object> _tplSubstitutionMappings() {
+        if(tpl.get(SUBSTITUTION_MAPPINGS) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(SUBSTITUTION_MAPPINGS);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    private LinkedHashMap<String,Object> _tplGroups() {
+        if(tpl.get(GROUPS) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(GROUPS);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    private ArrayList<Object> _tplPolicies() {
+        if(tpl.get(POLICIES) != null) {
+        	return (ArrayList<Object>)tpl.get(POLICIES);
+        }
+        else {
+        	return new ArrayList<Object>();
+        }
+    }
+
+    private void _validateField() {
+    	for(String name: tpl.keySet()) {
+    		boolean bFound = false;
+    		for(String section: SECTIONS) {
+    			if(name.equals(section)) {
+    				bFound = true;
+    				break;
+    			}
+    		}
+    		if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"UnknownFieldError: TopologyTemplate contains unknown field \"%s\"",name));
+    		}
+    	}
+    }
+
+    @SuppressWarnings("unchecked")
+	private void _processIntrinsicFunctions() {
+        // Process intrinsic functions
+
+        // Current implementation processes functions within node template
+        // properties, requirements, interfaces inputs and template outputs.
+    	
+    	if(nodeTemplates != null) {
+    		for(NodeTemplate nt: nodeTemplates) {
+    			for(Property prop: nt.getPropertiesObjects()) {
+    				prop.setValue(Function.getFunction(this,nt,prop.getValue()));
+    			}
+    			for(InterfacesDef ifd: nt.getInterfaces()) {
+    				LinkedHashMap<String,Object> ifin = ifd.getInputs();
+    				if(ifin != null) {
+    					for(Map.Entry<String,Object> me: ifin.entrySet()) {
+    						String name = me.getKey();
+    						Object value = Function.getFunction(this,nt,me.getValue());
+    						ifd.setInput(name,value);
+    					}
+    				}
+    			}
+    			if(nt.getRequirements() != null &&
+    					nt.getRequirements() instanceof ArrayList) {
+    				for(Object oreq: nt.getRequirements()) {
+    					LinkedHashMap<String,Object> req = (LinkedHashMap<String,Object>)oreq;
+    					LinkedHashMap<String,Object> rel = req;
+    					for(String reqName: req.keySet()) {
+    						Object reqItem = req.get(reqName);
+    						if(reqItem instanceof LinkedHashMap) {
+    							Object t = ((LinkedHashMap<String,Object>)reqItem).get("relationship");
+    							// it can be a string or a LHM...
+    							if(t instanceof LinkedHashMap) {
+    								rel = (LinkedHashMap<String,Object>)t;
+    							}
+    							else {
+    								// we set it to null to fail the next test
+    								// and avoid the get("proprties")
+    								rel = null;
+    							}
+    							break;
+    						}
+    					}
+    					if(rel != null && rel.get("properties") != null) {
+    						LinkedHashMap<String,Object> relprops = 
+    								(LinkedHashMap<String,Object>)rel.get("properties");
+    						for(String key: relprops.keySet()) {
+    							Object value = relprops.get(key);
+    							Object func = Function.getFunction(this,req,value);
+    							relprops.put(key,func);
+    						}
+    					}
+    				}
+    			}
+    			if(nt.getCapabilitiesObjects() != null) {
+    				for(Capability cap: nt.getCapabilitiesObjects()) {
+    					if(cap.getPropertiesObjects() != null) {
+    						for(Property prop: cap.getPropertiesObjects()) {
+    							Object propvalue = Function.getFunction(this,nt,prop.getValue());
+    							if(propvalue instanceof GetInput) {
+    								propvalue = ((GetInput)propvalue).result();
+    								for(String p: cap.getProperties().keySet()) {
+    									//Object v = cap.getProperties().get(p);
+    									if(p.equals(prop.getName())) {
+    										cap.setProperty(p,propvalue);
+    									}
+    								}
+    							}
+    						}
+    					}
+    				}
+    			}
+    			for(RelationshipType rel: nt.getRelationships().keySet()) {
+    				NodeTemplate node = nt.getRelationships().get(rel);
+    				ArrayList<RelationshipTemplate> relTpls = node.getRelationshipTemplate();
+    				if(relTpls != null) {
+    					for(RelationshipTemplate relTpl: relTpls) {
+    			    		// TT 5
+    						for(InterfacesDef iface: relTpl.getInterfaces()) {
+    							if(iface.getInputs() != null) {
+    								for(String name: iface.getInputs().keySet()) {
+    									Object value = iface.getInputs().get(name);
+    									Object func = Function.getFunction(
+    											this,
+    											relTpl,
+    											value);
+    									iface.setInput(name,func);
+    								}
+    							}
+    						}
+    					}
+    				}
+    			}
+    		}
+    	}
+    	for(Output output: outputs) {
+    		Object func = Function.getFunction(this,outputs,output.getValue());
+    		if(func instanceof GetAttribute) {
+    			output.setAttr(Output.VALUE,func);
+    		}
+    	}
+    }
+    
+    public static String getSubMappingNodeType(LinkedHashMap<String,Object> topologyTpl) {
+    	if(topologyTpl != null && topologyTpl instanceof LinkedHashMap) { 
+    		Object submapTpl = topologyTpl.get(SUBSTITUTION_MAPPINGS);
+    		return SubstitutionMappings.stGetNodeType((LinkedHashMap<String,Object>)submapTpl);
+    	}
+    	return null;
+    }
+    
+    // getters
+    
+	public LinkedHashMap<String,Object> getTpl() {
+		return tpl;
+	}
+	
+	public LinkedHashMap<String,Object> getMetadata() {
+		return metaData;
+	}
+	
+	public ArrayList<Input> getInputs() {
+		return inputs;
+	}
+	
+	public ArrayList<Output> getOutputs() {
+		return outputs;
+	}
+	
+	public ArrayList<Policy> getPolicies() {
+		return policies;
+	}
+	
+	public ArrayList<RelationshipTemplate> getRelationshipTemplates() {
+		return relationshipTemplates;
+	}
+
+	public ArrayList<NodeTemplate> getNodeTemplates() {
+		return nodeTemplates;
+	}
+	
+	public ArrayList<Group> getGroups() {
+		return groups;
+	}
+	
+	public SubstitutionMappings getSubstitutionMappings() {
+		return substitutionMappings;
+	}
+
+	public LinkedHashMap<String,Object> getParsedParams() {
+		return parsedParams;
+	}
+}
+
+/*python
+
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+
+import logging
+
+from toscaparser.common import exception
+from toscaparser.dataentity import DataEntity
+from toscaparser import functions
+from toscaparser.groups import Group
+from toscaparser.nodetemplate import NodeTemplate
+from toscaparser.parameters import Input
+from toscaparser.parameters import Output
+from toscaparser.policy import Policy
+from toscaparser.relationship_template import RelationshipTemplate
+from toscaparser.substitution_mappings import SubstitutionMappings
+from toscaparser.tpl_relationship_graph import ToscaGraph
+from toscaparser.utils.gettextutils import _
+
+
+# Topology template key names
+SECTIONS = (DESCRIPTION, INPUTS, NODE_TEMPLATES,
+            RELATIONSHIP_TEMPLATES, OUTPUTS, GROUPS,
+            SUBSTITUION_MAPPINGS, POLICIES) = \
+           ('description', 'inputs', 'node_templates',
+            'relationship_templates', 'outputs', 'groups',
+            'substitution_mappings', 'policies')
+
+log = logging.getLogger("tosca.model")
+
+
+class TopologyTemplate(object):
+
+    '''Load the template data.'''
+    def __init__(self, template, custom_defs,
+                 rel_types=None, parsed_params=None,
+                 sub_mapped_node_template=None):
+        self.tpl = template
+        self.sub_mapped_node_template = sub_mapped_node_template
+        if self.tpl:
+            self.custom_defs = custom_defs
+            self.rel_types = rel_types
+            self.parsed_params = parsed_params
+            self._validate_field()
+            self.description = self._tpl_description()
+            self.inputs = self._inputs()
+            self.relationship_templates = self._relationship_templates()
+            self.nodetemplates = self._nodetemplates()
+            self.outputs = self._outputs()
+            if hasattr(self, 'nodetemplates'):
+                self.graph = ToscaGraph(self.nodetemplates)
+            self.groups = self._groups()
+            self.policies = self._policies()
+            self._process_intrinsic_functions()
+            self.substitution_mappings = self._substitution_mappings()
+
+    def _inputs(self):
+        inputs = []
+        for name, attrs in self._tpl_inputs().items():
+            input = Input(name, attrs)
+            if self.parsed_params and name in self.parsed_params:
+                input.validate(self.parsed_params[name])
+            else:
+                default = input.default
+                if default:
+                    input.validate(default)
+            if (self.parsed_params and input.name not in self.parsed_params
+                or self.parsed_params is None) and input.required \
+                    and input.default is None:
+                log.warning(_('The required parameter %s '
+                              'is not provided') % input.name)
+
+            inputs.append(input)
+        return inputs
+
+    def _nodetemplates(self):
+        nodetemplates = []
+        tpls = self._tpl_nodetemplates()
+        if tpls:
+            for name in tpls:
+                tpl = NodeTemplate(name, tpls, self.custom_defs,
+                                   self.relationship_templates,
+                                   self.rel_types)
+                if (tpl.type_definition and
+                    (tpl.type in tpl.type_definition.TOSCA_DEF or
+                     (tpl.type not in tpl.type_definition.TOSCA_DEF and
+                      bool(tpl.custom_def)))):
+                    tpl.validate(self)
+                    nodetemplates.append(tpl)
+        return nodetemplates
+
+    def _relationship_templates(self):
+        rel_templates = []
+        tpls = self._tpl_relationship_templates()
+        for name in tpls:
+            tpl = RelationshipTemplate(tpls[name], name, self.custom_defs)
+            rel_templates.append(tpl)
+        return rel_templates
+
+    def _outputs(self):
+        outputs = []
+        for name, attrs in self._tpl_outputs().items():
+            output = Output(name, attrs)
+            output.validate()
+            outputs.append(output)
+        return outputs
+
+    def _substitution_mappings(self):
+        tpl_substitution_mapping = self._tpl_substitution_mappings()
+        # if tpl_substitution_mapping and self.sub_mapped_node_template:
+        if tpl_substitution_mapping:
+            return SubstitutionMappings(tpl_substitution_mapping,
+                                        self.nodetemplates,
+                                        self.inputs,
+                                        self.outputs,
+                                        self.sub_mapped_node_template,
+                                        self.custom_defs)
+
+    def _policies(self):
+        policies = []
+        for policy in self._tpl_policies():
+            for policy_name, policy_tpl in policy.items():
+                target_list = policy_tpl.get('targets')
+                if target_list and len(target_list) >= 1:
+                    target_objects = []
+                    targets_type = "groups"
+                    target_objects = self._get_policy_groups(target_list)
+                    if not target_objects:
+                        targets_type = "node_templates"
+                        target_objects = self._get_group_members(target_list)
+                    policyObj = Policy(policy_name, policy_tpl,
+                                       target_objects, targets_type,
+                                       self.custom_defs)
+                    policies.append(policyObj)
+        return policies
+
+    def _groups(self):
+        groups = []
+        member_nodes = None
+        for group_name, group_tpl in self._tpl_groups().items():
+            member_names = group_tpl.get('members')
+            if member_names is not None:
+                DataEntity.validate_datatype('list', member_names)
+                if len(member_names) < 1 or \
+                        len(member_names) != len(set(member_names)):
+                    exception.ExceptionCollector.appendException(
+                        exception.InvalidGroupTargetException(
+                            message=_('Member nodes "%s" should be >= 1 '
+                                      'and not repeated') % member_names))
+                else:
+                    member_nodes = self._get_group_members(member_names)
+            group = Group(group_name, group_tpl,
+                          member_nodes,
+                          self.custom_defs)
+            groups.append(group)
+        return groups
+
+    def _get_group_members(self, member_names):
+        member_nodes = []
+        self._validate_group_members(member_names)
+        for member in member_names:
+            for node in self.nodetemplates:
+                if node.name == member:
+                    member_nodes.append(node)
+        return member_nodes
+
+    def _get_policy_groups(self, member_names):
+        member_groups = []
+        for member in member_names:
+            for group in self.groups:
+                if group.name == member:
+                    member_groups.append(group)
+        return member_groups
+
+    def _validate_group_members(self, members):
+        node_names = []
+        for node in self.nodetemplates:
+            node_names.append(node.name)
+        for member in members:
+            if member not in node_names:
+                exception.ExceptionCollector.appendException(
+                    exception.InvalidGroupTargetException(
+                        message=_('Target member "%s" is not found in '
+                                  'node_templates') % member))
+
+    # topology template can act like node template
+    # it is exposed by substitution_mappings.
+    def nodetype(self):
+        return self.substitution_mappings.node_type \
+            if self.substitution_mappings else None
+
+    def capabilities(self):
+        return self.substitution_mappings.capabilities \
+            if self.substitution_mappings else None
+
+    def requirements(self):
+        return self.substitution_mappings.requirements \
+            if self.substitution_mappings else None
+
+    def _tpl_description(self):
+        description = self.tpl.get(DESCRIPTION)
+        if description:
+            return description.rstrip()
+
+    def _tpl_inputs(self):
+        return self.tpl.get(INPUTS) or {}
+
+    def _tpl_nodetemplates(self):
+        return self.tpl.get(NODE_TEMPLATES)
+
+    def _tpl_relationship_templates(self):
+        return self.tpl.get(RELATIONSHIP_TEMPLATES) or {}
+
+    def _tpl_outputs(self):
+        return self.tpl.get(OUTPUTS) or {}
+
+    def _tpl_substitution_mappings(self):
+        return self.tpl.get(SUBSTITUION_MAPPINGS) or {}
+
+    def _tpl_groups(self):
+        return self.tpl.get(GROUPS) or {}
+
+    def _tpl_policies(self):
+        return self.tpl.get(POLICIES) or {}
+
+    def _validate_field(self):
+        for name in self.tpl:
+            if name not in SECTIONS:
+                exception.ExceptionCollector.appendException(
+                    exception.UnknownFieldError(what='Template', field=name))
+
+    def _process_intrinsic_functions(self):
+        """Process intrinsic functions
+
+        Current implementation processes functions within node template
+        properties, requirements, interfaces inputs and template outputs.
+        """
+        if hasattr(self, 'nodetemplates'):
+            for node_template in self.nodetemplates:
+                for prop in node_template.get_properties_objects():
+                    prop.value = functions.get_function(self,
+                                                        node_template,
+                                                        prop.value)
+                for interface in node_template.interfaces:
+                    if interface.inputs:
+                        for name, value in interface.inputs.items():
+                            interface.inputs[name] = functions.get_function(
+                                self,
+                                node_template,
+                                value)
+                if node_template.requirements and \
+                   isinstance(node_template.requirements, list):
+                    for req in node_template.requirements:
+                        rel = req
+                        for req_name, req_item in req.items():
+                            if isinstance(req_item, dict):
+                                rel = req_item.get('relationship')
+                                break
+                        if rel and 'properties' in rel:
+                            for key, value in rel['properties'].items():
+                                rel['properties'][key] = \
+                                    functions.get_function(self,
+                                                           req,
+                                                           value)
+                if node_template.get_capabilities_objects():
+                    for cap in node_template.get_capabilities_objects():
+                        if cap.get_properties_objects():
+                            for prop in cap.get_properties_objects():
+                                propvalue = functions.get_function(
+                                    self,
+                                    node_template,
+                                    prop.value)
+                                if isinstance(propvalue, functions.GetInput):
+                                    propvalue = propvalue.result()
+                                    for p, v in cap._properties.items():
+                                        if p == prop.name:
+                                            cap._properties[p] = propvalue
+                for rel, node in node_template.relationships.items():
+                    rel_tpls = node.relationship_tpl
+                    if rel_tpls:
+                        for rel_tpl in rel_tpls:
+                            for interface in rel_tpl.interfaces:
+                                if interface.inputs:
+                                    for name, value in \
+                                            interface.inputs.items():
+                                        interface.inputs[name] = \
+                                            functions.get_function(self,
+                                                                   rel_tpl,
+                                                                   value)
+        for output in self.outputs:
+            func = functions.get_function(self, self.outputs, output.value)
+            if isinstance(func, functions.GetAttribute):
+                output.attrs[output.VALUE] = func
+
+    @classmethod
+    def get_sub_mapping_node_type(cls, topology_tpl):
+        if topology_tpl and isinstance(topology_tpl, dict):
+            submap_tpl = topology_tpl.get(SUBSTITUION_MAPPINGS)
+            return SubstitutionMappings.get_node_type(submap_tpl)
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/TopologyTemplate.java.orig b/src/main/java/org/openecomp/sdc/toscaparser/api/TopologyTemplate.java.orig
new file mode 100644
index 0000000..3af4b34
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/TopologyTemplate.java.orig
@@ -0,0 +1,857 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.InterfacesDef;
+import org.openecomp.sdc.toscaparser.api.elements.NodeType;
+import org.openecomp.sdc.toscaparser.api.elements.RelationshipType;
+import org.openecomp.sdc.toscaparser.api.functions.Function;
+import org.openecomp.sdc.toscaparser.api.functions.GetAttribute;
+import org.openecomp.sdc.toscaparser.api.functions.GetInput;
+import org.openecomp.sdc.toscaparser.api.parameters.Input;
+import org.openecomp.sdc.toscaparser.api.parameters.Output;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class TopologyTemplate {
+
+	private static final String DESCRIPTION = "description";
+	private static final String INPUTS = "inputs";
+	private static final String NODE_TEMPLATES = "node_templates";
+	private static final String RELATIONSHIP_TEMPLATES = "relationship_templates";
+	private static final String OUTPUTS = "outputs";
+	private static final String GROUPS = "groups";
+	private static final String SUBSTITUTION_MAPPINGS = "substitution_mappings";
+	private static final String POLICIES = "policies";
+	private static final String METADATA = "metadata";
+	
+	private static String SECTIONS[] = {
+				DESCRIPTION, INPUTS, NODE_TEMPLATES, RELATIONSHIP_TEMPLATES, 
+				OUTPUTS, GROUPS,  SUBSTITUTION_MAPPINGS, POLICIES, METADATA
+			};
+
+    private LinkedHashMap<String,Object> tpl;
+	LinkedHashMap<String,Object> metaData;
+    private ArrayList<Input> inputs;
+    private ArrayList<Output> outputs;
+    private ArrayList<RelationshipTemplate> relationshipTemplates;
+    private ArrayList<NodeTemplate> nodeTemplates;
+	private LinkedHashMap<String,Object> customDefs;
+	private LinkedHashMap<String,Object> relTypes;//TYPE
+    private NodeTemplate subMappedNodeTemplate;
+    private ArrayList<Group> groups;
+    private ArrayList<Policy> policies;
+    private LinkedHashMap<String,Object> parsedParams = null;//TYPE
+    private String description;
+    private ToscaGraph graph;
+    private SubstitutionMappings substitutionMappings;
+	
+	public TopologyTemplate(
+			LinkedHashMap<String,Object> _template, 
+			LinkedHashMap<String,Object> _customDefs,
+			LinkedHashMap<String,Object> _relTypes,//TYPE
+            LinkedHashMap<String, Object> _parsedParams,
+            NodeTemplate  _subMappedNodeTemplate) {
+
+		tpl = _template;
+		if(tpl != null) {
+			subMappedNodeTemplate = _subMappedNodeTemplate;
+			metaData = _metaData();
+			customDefs = _customDefs;
+			relTypes = _relTypes;
+			parsedParams = _parsedParams;
+			_validateField();
+			description = _tplDescription();
+			inputs = _inputs();
+	        relationshipTemplates =_relationshipTemplates();
+	        nodeTemplates = _nodeTemplates();
+	        outputs = _outputs();
+	        if(nodeTemplates != null) {
+	        	graph = new ToscaGraph(nodeTemplates);
+	        }
+	        groups = _groups();
+	        policies = _policies();
+	        _processIntrinsicFunctions();
+            substitutionMappings = _substitutionMappings();
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	private ArrayList<Input> _inputs() {
+		//DumpUtils.dumpYaml(customDefs,0);
+		ArrayList<Input> alInputs = new ArrayList<>();
+		for(String name: _tplInputs().keySet()) {
+			Object attrs = _tplInputs().get(name);
+			Input input = new Input(name,(LinkedHashMap<String,Object>)attrs,customDefs);
+            if(parsedParams != null && parsedParams.get(name) != null) {
+            	input.validate(parsedParams.get(name));
+            }
+            else {
+                Object _default = input.getDefault();
+                if(_default != null) {
+                    input.validate(_default);
+                }
+            }
+            if((parsedParams != null && parsedParams.get(input.getName()) == null || parsedParams == null)
+            		 && input.isRequired() && input.getDefault() == null) {
+            	System.out.format("Log warning: The required parameter \"%s\" is not provided\n",input.getName());
+            }
+            alInputs.add(input);
+		}
+        return alInputs;
+		
+	}
+
+	private LinkedHashMap<String,Object> _metaData() {
+        if(tpl.get(METADATA) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(METADATA);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+	
+	}
+
+	private ArrayList<NodeTemplate> _nodeTemplates() {
+		ArrayList<NodeTemplate> alNodeTemplates = new ArrayList<>();
+		LinkedHashMap<String,Object> tpls = _tplNodeTemplates();
+		if(tpls != null) {
+			for(String name: tpls.keySet()) {
+				NodeTemplate tpl = new NodeTemplate(name,
+													tpls,
+													customDefs,
+													relationshipTemplates,
+													relTypes);
+				if(tpl.getTypeDefinition() != null) {
+					boolean b = NodeType.TOSCA_DEF.get(tpl.getType()) != null;
+					if(b || (tpl.getCustomDef() != null && !tpl.getCustomDef().isEmpty())) {
+						tpl.validate();
+						alNodeTemplates.add(tpl);
+					}
+				}
+			}
+		}
+		return alNodeTemplates;
+	}
+	
+	@SuppressWarnings("unchecked")
+	private ArrayList<RelationshipTemplate> _relationshipTemplates() {
+		ArrayList<RelationshipTemplate> alRelationshipTemplates = new ArrayList<>();
+		LinkedHashMap<String,Object> tpls = _tplRelationshipTemplates();
+		if(tpls != null) {
+			for(String name: tpls.keySet()) {
+				RelationshipTemplate tpl = new RelationshipTemplate(
+						(LinkedHashMap<String,Object>)tpls.get(name),name,customDefs,null,null);
+						
+				alRelationshipTemplates.add(tpl);
+			}
+		}
+		return alRelationshipTemplates;
+	}
+	
+	private ArrayList<Output> _outputs() {
+		ArrayList<Output> alOutputs = new ArrayList<>();
+		for(Map.Entry<String,Object> me: _tplOutputs().entrySet()) {
+			String oname = me.getKey();
+			LinkedHashMap<String,Object> oattrs = (LinkedHashMap<String,Object>)me.getValue(); 
+			Output o = new Output(oname,oattrs);
+			o.validate();
+			alOutputs.add(o);
+		}
+		return alOutputs;
+	}
+	
+	private SubstitutionMappings _substitutionMappings() {
+		LinkedHashMap<String,Object> tplSubstitutionMapping = (LinkedHashMap<String,Object>) _tplSubstitutionMappings();
+		
+		//*** the commenting-out below and the weaker condition are in the Python source
+		// #if tpl_substitution_mapping and self.sub_mapped_node_template:
+		if(tplSubstitutionMapping != null && tplSubstitutionMapping.size() > 0) {
+			return new SubstitutionMappings(tplSubstitutionMapping,
+					                    nodeTemplates,
+					                    inputs,
+					                    outputs,
+					                    groups,
+					                    subMappedNodeTemplate,
+					                    customDefs);
+		}
+		return null;
+		
+	}
+	
+	@SuppressWarnings("unchecked")
+	private ArrayList<Policy> _policies() {
+		ArrayList<Policy> alPolicies = new ArrayList<>();
+		for(Object po: _tplPolicies()) {
+			LinkedHashMap<String,Object> policy = (LinkedHashMap<String,Object>)po;
+			for(Map.Entry<String,Object> me: policy.entrySet()) {
+				String policyName = me.getKey();
+				LinkedHashMap<String,Object> policyTpl = (LinkedHashMap<String,Object>)me.getValue();
+				ArrayList<String> targetList = (ArrayList<String>)policyTpl.get("targets");
+				//ArrayList<Object> targetObjects = new ArrayList<>();
+				ArrayList<NodeTemplate> targetNodes = new ArrayList<>();
+				ArrayList<Object> targetObjects = new ArrayList<>();
+				ArrayList<Group> targetGroups = new ArrayList<>();
+				String targetsType = "groups"; 
+				if(targetList != null && targetList.size() >= 1) {
+                    targetGroups = _getPolicyGroups(targetList);
+                    if(targetGroups == null) {
+                    	targetsType = "node_templates";
+                        targetNodes = _getGroupMembers(targetList);
+                        for(NodeTemplate nt: targetNodes) {
+                        	targetObjects.add(nt);
+                        }
+                    }
+                    else {
+                    	for(Group gr: targetGroups) {
+                    		targetObjects.add(gr);
+                    	}
+                    }
+				}
+                Policy policyObj = new Policy(policyName, 
+                							  policyTpl,
+		                                      targetObjects, 
+		                                      targetsType,
+		                                      customDefs);
+                alPolicies.add(policyObj);
+			}
+		}
+        return alPolicies;
+	}
+	
+	private ArrayList<Group> _groups() {
+		ArrayList<Group> groups = new ArrayList<>();
+		ArrayList<NodeTemplate> memberNodes  = null;
+		for(Map.Entry<String,Object> me: _tplGroups().entrySet()) {
+			String groupName = me.getKey();
+			LinkedHashMap<String,Object> groupTpl = (LinkedHashMap<String,Object>)me.getValue();
+			ArrayList<String> memberNames = (ArrayList<String>)groupTpl.get("members");
+			if(memberNames != null) {
+                DataEntity.validateDatatype("list", memberNames,null,null,null);
+				if(memberNames.size() < 1 || 
+				       (new HashSet<String>(memberNames)).size() != memberNames.size()) {
+                    ThreadLocalsHolder.getCollector().appendException(String.format(
+                            "InvalidGroupTargetException: Member nodes \"%s\" should be >= 1 and not repeated",
+                            memberNames.toString()));
+				}
+				else {
+					memberNodes = _getGroupMembers(memberNames);
+				}
+			}
+            Group group = new Group(groupName,
+            						groupTpl,
+            						memberNodes,
+            						customDefs);
+            groups.add(group);
+		}
+		return groups;
+	}
+	
+	private ArrayList<NodeTemplate> _getGroupMembers(ArrayList<String> memberNames) {
+		ArrayList<NodeTemplate> memberNodes = new ArrayList<>();
+		_validateGroupMembers(memberNames);
+		for(String member: memberNames) {
+			for(NodeTemplate node: nodeTemplates) {
+				if(member.equals(node.getName())) {
+					memberNodes.add(node);
+				}
+			}
+		}
+		return memberNodes;
+	}
+	
+	private ArrayList<Group> _getPolicyGroups(ArrayList<String> memberNames) {
+		ArrayList<Group> memberGroups = new ArrayList<>();
+		for(String member: memberNames) {
+			for(Group group: groups) {
+				if(member.equals(group.getName())) {
+					memberGroups.add(group);
+				}
+			}
+		}
+		return memberGroups;
+	}
+	
+	private void _validateGroupMembers(ArrayList<String> members) {
+		ArrayList<String> nodeNames = new ArrayList<>();
+		for(NodeTemplate node: nodeTemplates) {
+			nodeNames.add(node.getName());
+		}
+		for(String member: members) {
+			if(!nodeNames.contains(member)) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "InvalidGroupTargetException: Target member \"%s\" is not found in \"nodeTemplates\"",member));
+			}
+		}
+	}
+	
+	// topology template can act like node template
+	// it is exposed by substitution_mappings.
+
+	public String nodetype() {
+		return substitutionMappings.getNodeType();
+	}
+	
+	public LinkedHashMap<String,Object> capabilities() {
+		return substitutionMappings.getCapabilities();
+	}
+	
+	public LinkedHashMap<String,Object> requirements() {
+		return substitutionMappings.getRequirements();
+	}
+
+	private String _tplDescription() {
+        return (String)tpl.get(DESCRIPTION);
+        //if description:
+        //	return description.rstrip()
+	}
+
+	@SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _tplInputs() {
+        if(tpl.get(INPUTS) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(INPUTS);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _tplNodeTemplates() {
+        return (LinkedHashMap<String,Object>)tpl.get(NODE_TEMPLATES);
+    }
+
+    @SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _tplRelationshipTemplates() {
+        if(tpl.get(RELATIONSHIP_TEMPLATES) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(RELATIONSHIP_TEMPLATES);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+ 	private LinkedHashMap<String,Object> _tplOutputs() {
+         if(tpl.get(OUTPUTS) != null) {
+         	return (LinkedHashMap<String,Object>)tpl.get(OUTPUTS);
+         }
+         else {
+         	return new LinkedHashMap<String,Object>();
+         }
+     }
+
+    @SuppressWarnings("unchecked")
+    private LinkedHashMap<String,Object> _tplSubstitutionMappings() {
+        if(tpl.get(SUBSTITUTION_MAPPINGS) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(SUBSTITUTION_MAPPINGS);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    private LinkedHashMap<String,Object> _tplGroups() {
+        if(tpl.get(GROUPS) != null) {
+        	return (LinkedHashMap<String,Object>)tpl.get(GROUPS);
+        }
+        else {
+        	return new LinkedHashMap<String,Object>();
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    private ArrayList<Object> _tplPolicies() {
+        if(tpl.get(POLICIES) != null) {
+        	return (ArrayList<Object>)tpl.get(POLICIES);
+        }
+        else {
+        	return new ArrayList<Object>();
+        }
+    }
+
+    private void _validateField() {
+    	for(String name: tpl.keySet()) {
+    		boolean bFound = false;
+    		for(String section: SECTIONS) {
+    			if(name.equals(section)) {
+    				bFound = true;
+    				break;
+    			}
+    		}
+    		if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"UnknownFieldError: TopologyTemplate contains unknown field \"%s\"",name));
+    		}
+    	}
+    }
+
+    @SuppressWarnings("unchecked")
+	private void _processIntrinsicFunctions() {
+        // Process intrinsic functions
+
+        // Current implementation processes functions within node template
+        // properties, requirements, interfaces inputs and template outputs.
+    	
+    	if(nodeTemplates != null) {
+    		for(NodeTemplate nt: nodeTemplates) {
+    			for(Property prop: nt.getPropertiesObjects()) {
+    				prop.setValue(Function.getFunction(this,nt,prop.getValue()));
+    			}
+    			for(InterfacesDef ifd: nt.getInterfaces()) {
+    				LinkedHashMap<String,Object> ifin = ifd.getInputs();
+    				if(ifin != null) {
+    					for(Map.Entry<String,Object> me: ifin.entrySet()) {
+    						String name = me.getKey();
+    						Object value = Function.getFunction(this,nt,me.getValue());
+    						ifd.setInput(name,value);
+    					}
+    				}
+    			}
+    			if(nt.getRequirements() != null &&
+    					nt.getRequirements() instanceof ArrayList) {
+    				for(Object oreq: nt.getRequirements()) {
+    					LinkedHashMap<String,Object> req = (LinkedHashMap<String,Object>)oreq;
+    					LinkedHashMap<String,Object> rel = req;
+    					for(String reqName: req.keySet()) {
+    						Object reqItem = req.get(reqName);
+    						if(reqItem instanceof LinkedHashMap) {
+    							Object t = ((LinkedHashMap<String,Object>)reqItem).get("relationship");
+    							// it can be a string or a LHM...
+    							if(t instanceof LinkedHashMap) {
+    								rel = (LinkedHashMap<String,Object>)t;
+    							}
+    							else {
+    								// we set it to null to fail the next test
+    								// and avoid the get("proprties")
+    								rel = null;
+    							}
+    							break;
+    						}
+    					}
+    					if(rel != null && rel.get("properties") != null) {
+    						LinkedHashMap<String,Object> relprops = 
+    								(LinkedHashMap<String,Object>)rel.get("properties");
+    						for(String key: relprops.keySet()) {
+    							Object value = relprops.get(key);
+    							Object func = Function.getFunction(this,req,value);
+    							relprops.put(key,func);
+    						}
+    					}
+    				}
+    			}
+    			if(nt.getCapabilitiesObjects() != null) {
+    				for(Capability cap: nt.getCapabilitiesObjects()) {
+    					if(cap.getPropertiesObjects() != null) {
+    						for(Property prop: cap.getPropertiesObjects()) {
+    							Object propvalue = Function.getFunction(this,nt,prop.getValue());
+    							if(propvalue instanceof GetInput) {
+    								propvalue = ((GetInput)propvalue).result();
+    								for(String p: cap.getProperties().keySet()) {
+    									//Object v = cap.getProperties().get(p);
+    									if(p.equals(prop.getName())) {
+    										cap.setProperty(p,propvalue);
+    									}
+    								}
+    							}
+    						}
+    					}
+    				}
+    			}
+    			for(RelationshipType rel: nt.getRelationships().keySet()) {
+    				NodeTemplate node = nt.getRelationships().get(rel);
+    				ArrayList<RelationshipTemplate> relTpls = node.getRelationshipTemplate();
+    				if(relTpls != null) {
+    					for(RelationshipTemplate relTpl: relTpls) {
+    			    		// TT 5
+    						for(InterfacesDef iface: relTpl.getInterfaces()) {
+    							if(iface.getInputs() != null) {
+    								for(String name: iface.getInputs().keySet()) {
+    									Object value = iface.getInputs().get(name);
+    									Object func = Function.getFunction(
+    											this,
+    											relTpl,
+    											value);
+    									iface.setInput(name,func);
+    								}
+    							}
+    						}
+    					}
+    				}
+    			}
+    		}
+    	}
+    	for(Output output: outputs) {
+    		Object func = Function.getFunction(this,outputs,output.getValue());
+    		if(func instanceof GetAttribute) {
+    			output.setAttr(Output.VALUE,func);
+    		}
+    	}
+    }
+    
+    public static String getSubMappingNodeType(LinkedHashMap<String,Object> topologyTpl) {
+    	if(topologyTpl != null && topologyTpl instanceof LinkedHashMap) { 
+    		Object submapTpl = topologyTpl.get(SUBSTITUTION_MAPPINGS);
+    		return SubstitutionMappings.stGetNodeType((LinkedHashMap<String,Object>)submapTpl);
+    	}
+    	return null;
+    }
+    
+    // getters
+    
+	public LinkedHashMap<String,Object> getTpl() {
+		return tpl;
+	}
+	
+	public LinkedHashMap<String,Object> getMetadata() {
+		return metaData;
+	}
+	
+	public ArrayList<Input> getInputs() {
+		return inputs;
+	}
+	
+	public ArrayList<Output> getOutputs() {
+		return outputs;
+	}
+	
+	public ArrayList<Policy> getPolicies() {
+		return policies;
+	}
+	
+	public ArrayList<RelationshipTemplate> getRelationshipTemplates() {
+		return relationshipTemplates;
+	}
+
+	public ArrayList<NodeTemplate> getNodeTemplates() {
+		return nodeTemplates;
+	}
+	
+	public ArrayList<Group> getGroups() {
+		return groups;
+	}
+	
+	public SubstitutionMappings getSubstitutionMappings() {
+		return substitutionMappings;
+	}
+
+	public LinkedHashMap<String,Object> getParsedParams() {
+		return parsedParams;
+	}
+}
+
+/*python
+
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+
+import logging
+
+from toscaparser.common import exception
+from toscaparser.dataentity import DataEntity
+from toscaparser import functions
+from toscaparser.groups import Group
+from toscaparser.nodetemplate import NodeTemplate
+from toscaparser.parameters import Input
+from toscaparser.parameters import Output
+from toscaparser.policy import Policy
+from toscaparser.relationship_template import RelationshipTemplate
+from toscaparser.substitution_mappings import SubstitutionMappings
+from toscaparser.tpl_relationship_graph import ToscaGraph
+from toscaparser.utils.gettextutils import _
+
+
+# Topology template key names
+SECTIONS = (DESCRIPTION, INPUTS, NODE_TEMPLATES,
+            RELATIONSHIP_TEMPLATES, OUTPUTS, GROUPS,
+            SUBSTITUION_MAPPINGS, POLICIES) = \
+           ('description', 'inputs', 'node_templates',
+            'relationship_templates', 'outputs', 'groups',
+            'substitution_mappings', 'policies')
+
+log = logging.getLogger("tosca.model")
+
+
+class TopologyTemplate(object):
+
+    '''Load the template data.'''
+    def __init__(self, template, custom_defs,
+                 rel_types=None, parsed_params=None,
+                 sub_mapped_node_template=None):
+        self.tpl = template
+        self.sub_mapped_node_template = sub_mapped_node_template
+        if self.tpl:
+            self.custom_defs = custom_defs
+            self.rel_types = rel_types
+            self.parsed_params = parsed_params
+            self._validate_field()
+            self.description = self._tpl_description()
+            self.inputs = self._inputs()
+            self.relationship_templates = self._relationship_templates()
+            self.nodetemplates = self._nodetemplates()
+            self.outputs = self._outputs()
+            if hasattr(self, 'nodetemplates'):
+                self.graph = ToscaGraph(self.nodetemplates)
+            self.groups = self._groups()
+            self.policies = self._policies()
+            self._process_intrinsic_functions()
+            self.substitution_mappings = self._substitution_mappings()
+
+    def _inputs(self):
+        inputs = []
+        for name, attrs in self._tpl_inputs().items():
+            input = Input(name, attrs)
+            if self.parsed_params and name in self.parsed_params:
+                input.validate(self.parsed_params[name])
+            else:
+                default = input.default
+                if default:
+                    input.validate(default)
+            if (self.parsed_params and input.name not in self.parsed_params
+                or self.parsed_params is None) and input.required \
+                    and input.default is None:
+                log.warning(_('The required parameter %s '
+                              'is not provided') % input.name)
+
+            inputs.append(input)
+        return inputs
+
+    def _nodetemplates(self):
+        nodetemplates = []
+        tpls = self._tpl_nodetemplates()
+        if tpls:
+            for name in tpls:
+                tpl = NodeTemplate(name, tpls, self.custom_defs,
+                                   self.relationship_templates,
+                                   self.rel_types)
+                if (tpl.type_definition and
+                    (tpl.type in tpl.type_definition.TOSCA_DEF or
+                     (tpl.type not in tpl.type_definition.TOSCA_DEF and
+                      bool(tpl.custom_def)))):
+                    tpl.validate(self)
+                    nodetemplates.append(tpl)
+        return nodetemplates
+
+    def _relationship_templates(self):
+        rel_templates = []
+        tpls = self._tpl_relationship_templates()
+        for name in tpls:
+            tpl = RelationshipTemplate(tpls[name], name, self.custom_defs)
+            rel_templates.append(tpl)
+        return rel_templates
+
+    def _outputs(self):
+        outputs = []
+        for name, attrs in self._tpl_outputs().items():
+            output = Output(name, attrs)
+            output.validate()
+            outputs.append(output)
+        return outputs
+
+    def _substitution_mappings(self):
+        tpl_substitution_mapping = self._tpl_substitution_mappings()
+        # if tpl_substitution_mapping and self.sub_mapped_node_template:
+        if tpl_substitution_mapping:
+            return SubstitutionMappings(tpl_substitution_mapping,
+                                        self.nodetemplates,
+                                        self.inputs,
+                                        self.outputs,
+                                        self.sub_mapped_node_template,
+                                        self.custom_defs)
+
+    def _policies(self):
+        policies = []
+        for policy in self._tpl_policies():
+            for policy_name, policy_tpl in policy.items():
+                target_list = policy_tpl.get('targets')
+                if target_list and len(target_list) >= 1:
+                    target_objects = []
+                    targets_type = "groups"
+                    target_objects = self._get_policy_groups(target_list)
+                    if not target_objects:
+                        targets_type = "node_templates"
+                        target_objects = self._get_group_members(target_list)
+                    policyObj = Policy(policy_name, policy_tpl,
+                                       target_objects, targets_type,
+                                       self.custom_defs)
+                    policies.append(policyObj)
+        return policies
+
+    def _groups(self):
+        groups = []
+        member_nodes = None
+        for group_name, group_tpl in self._tpl_groups().items():
+            member_names = group_tpl.get('members')
+            if member_names is not None:
+                DataEntity.validate_datatype('list', member_names)
+                if len(member_names) < 1 or \
+                        len(member_names) != len(set(member_names)):
+                    exception.ExceptionCollector.appendException(
+                        exception.InvalidGroupTargetException(
+                            message=_('Member nodes "%s" should be >= 1 '
+                                      'and not repeated') % member_names))
+                else:
+                    member_nodes = self._get_group_members(member_names)
+            group = Group(group_name, group_tpl,
+                          member_nodes,
+                          self.custom_defs)
+            groups.append(group)
+        return groups
+
+    def _get_group_members(self, member_names):
+        member_nodes = []
+        self._validate_group_members(member_names)
+        for member in member_names:
+            for node in self.nodetemplates:
+                if node.name == member:
+                    member_nodes.append(node)
+        return member_nodes
+
+    def _get_policy_groups(self, member_names):
+        member_groups = []
+        for member in member_names:
+            for group in self.groups:
+                if group.name == member:
+                    member_groups.append(group)
+        return member_groups
+
+    def _validate_group_members(self, members):
+        node_names = []
+        for node in self.nodetemplates:
+            node_names.append(node.name)
+        for member in members:
+            if member not in node_names:
+                exception.ExceptionCollector.appendException(
+                    exception.InvalidGroupTargetException(
+                        message=_('Target member "%s" is not found in '
+                                  'node_templates') % member))
+
+    # topology template can act like node template
+    # it is exposed by substitution_mappings.
+    def nodetype(self):
+        return self.substitution_mappings.node_type \
+            if self.substitution_mappings else None
+
+    def capabilities(self):
+        return self.substitution_mappings.capabilities \
+            if self.substitution_mappings else None
+
+    def requirements(self):
+        return self.substitution_mappings.requirements \
+            if self.substitution_mappings else None
+
+    def _tpl_description(self):
+        description = self.tpl.get(DESCRIPTION)
+        if description:
+            return description.rstrip()
+
+    def _tpl_inputs(self):
+        return self.tpl.get(INPUTS) or {}
+
+    def _tpl_nodetemplates(self):
+        return self.tpl.get(NODE_TEMPLATES)
+
+    def _tpl_relationship_templates(self):
+        return self.tpl.get(RELATIONSHIP_TEMPLATES) or {}
+
+    def _tpl_outputs(self):
+        return self.tpl.get(OUTPUTS) or {}
+
+    def _tpl_substitution_mappings(self):
+        return self.tpl.get(SUBSTITUION_MAPPINGS) or {}
+
+    def _tpl_groups(self):
+        return self.tpl.get(GROUPS) or {}
+
+    def _tpl_policies(self):
+        return self.tpl.get(POLICIES) or {}
+
+    def _validate_field(self):
+        for name in self.tpl:
+            if name not in SECTIONS:
+                exception.ExceptionCollector.appendException(
+                    exception.UnknownFieldError(what='Template', field=name))
+
+    def _process_intrinsic_functions(self):
+        """Process intrinsic functions
+
+        Current implementation processes functions within node template
+        properties, requirements, interfaces inputs and template outputs.
+        """
+        if hasattr(self, 'nodetemplates'):
+            for node_template in self.nodetemplates:
+                for prop in node_template.get_properties_objects():
+                    prop.value = functions.get_function(self,
+                                                        node_template,
+                                                        prop.value)
+                for interface in node_template.interfaces:
+                    if interface.inputs:
+                        for name, value in interface.inputs.items():
+                            interface.inputs[name] = functions.get_function(
+                                self,
+                                node_template,
+                                value)
+                if node_template.requirements and \
+                   isinstance(node_template.requirements, list):
+                    for req in node_template.requirements:
+                        rel = req
+                        for req_name, req_item in req.items():
+                            if isinstance(req_item, dict):
+                                rel = req_item.get('relationship')
+                                break
+                        if rel and 'properties' in rel:
+                            for key, value in rel['properties'].items():
+                                rel['properties'][key] = \
+                                    functions.get_function(self,
+                                                           req,
+                                                           value)
+                if node_template.get_capabilities_objects():
+                    for cap in node_template.get_capabilities_objects():
+                        if cap.get_properties_objects():
+                            for prop in cap.get_properties_objects():
+                                propvalue = functions.get_function(
+                                    self,
+                                    node_template,
+                                    prop.value)
+                                if isinstance(propvalue, functions.GetInput):
+                                    propvalue = propvalue.result()
+                                    for p, v in cap._properties.items():
+                                        if p == prop.name:
+                                            cap._properties[p] = propvalue
+                for rel, node in node_template.relationships.items():
+                    rel_tpls = node.relationship_tpl
+                    if rel_tpls:
+                        for rel_tpl in rel_tpls:
+                            for interface in rel_tpl.interfaces:
+                                if interface.inputs:
+                                    for name, value in \
+                                            interface.inputs.items():
+                                        interface.inputs[name] = \
+                                            functions.get_function(self,
+                                                                   rel_tpl,
+                                                                   value)
+        for output in self.outputs:
+            func = functions.get_function(self, self.outputs, output.value)
+            if isinstance(func, functions.GetAttribute):
+                output.attrs[output.VALUE] = func
+
+    @classmethod
+    def get_sub_mapping_node_type(cls, topology_tpl):
+        if topology_tpl and isinstance(topology_tpl, dict):
+            submap_tpl = topology_tpl.get(SUBSTITUION_MAPPINGS)
+            return SubstitutionMappings.get_node_type(submap_tpl)
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/ToscaGraph.java b/src/main/java/org/openecomp/sdc/toscaparser/api/ToscaGraph.java
new file mode 100644
index 0000000..2de3bb9
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/ToscaGraph.java
@@ -0,0 +1,109 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.elements.RelationshipType;
+
+//import java.util.Iterator;
+
+public class ToscaGraph {
+    // Graph of Tosca Node Templates
+
+	private ArrayList<NodeTemplate> nodeTemplates;
+	private LinkedHashMap<String,NodeTemplate> vertices;
+	
+	public ToscaGraph(ArrayList<NodeTemplate> inodeTemplates) {
+		nodeTemplates = inodeTemplates;
+		vertices = new LinkedHashMap<String,NodeTemplate>();
+		_create();
+	}
+	
+	private void _createVertex(NodeTemplate node) {
+        if(vertices.get(node.getName()) == null) {
+            vertices.put(node.getName(),node);
+        }
+	}
+	
+	private void _createEdge(NodeTemplate node1,
+							 NodeTemplate node2,
+							 RelationshipType relation) {
+		if(vertices.get(node1.getName()) == null) {
+			_createVertex(node1);
+			vertices.get(node1.name)._addNext(node2,relation);
+		}
+	}
+	
+	public NodeTemplate vertex(String name) {
+        if(vertices.get(name) != null) {
+            return vertices.get(name);
+        }
+        return null;
+	}
+	
+//	public Iterator getIter() {
+//		return vertices.values().iterator();
+//	}
+	
+	private void _create() {
+		for(NodeTemplate node: nodeTemplates) {
+			LinkedHashMap<RelationshipType,NodeTemplate> relation = node.getRelationships();
+			if(relation != null) {
+				for(RelationshipType rel: relation.keySet()) {
+					NodeTemplate nodeTpls = relation.get(rel);
+					for(NodeTemplate tpl: nodeTemplates) {
+						if(tpl.getName().equals(nodeTpls.getName())) {
+							_createEdge(node,tpl,rel);
+						}
+					}
+				}
+			}
+			_createVertex(node);
+		}
+	}
+
+	@Override
+	public String toString() {
+		return "ToscaGraph{" +
+				"nodeTemplates=" + nodeTemplates +
+				", vertices=" + vertices +
+				'}';
+	}
+}
+
+/*python
+
+class ToscaGraph(object):
+    '''Graph of Tosca Node Templates.'''
+    def __init__(self, nodetemplates):
+        self.nodetemplates = nodetemplates
+        self.vertices = {}
+        self._create()
+
+    def _create_vertex(self, node):
+        if node not in self.vertices:
+            self.vertices[node.name] = node
+
+    def _create_edge(self, node1, node2, relationship):
+        if node1 not in self.vertices:
+            self._create_vertex(node1)
+        self.vertices[node1.name]._add_next(node2,
+                                            relationship)
+
+    def vertex(self, node):
+        if node in self.vertices:
+            return self.vertices[node]
+
+    def __iter__(self):
+        return iter(self.vertices.values())
+
+    def _create(self):
+        for node in self.nodetemplates:
+            relation = node.relationships
+            if relation:
+                for rel, nodetpls in relation.items():
+                    for tpl in self.nodetemplates:
+                        if tpl.name == nodetpls.name:
+                            self._create_edge(node, tpl, rel)
+            self._create_vertex(node)
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/ToscaTemplate.java b/src/main/java/org/openecomp/sdc/toscaparser/api/ToscaTemplate.java
new file mode 100644
index 0000000..b13a2a5
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/ToscaTemplate.java
@@ -0,0 +1,1002 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.*;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.common.JToscaException;
+import org.openecomp.sdc.toscaparser.api.elements.EntityType;
+import org.openecomp.sdc.toscaparser.api.elements.Metadata;
+import org.openecomp.sdc.toscaparser.api.extensions.ExtTools;
+import org.openecomp.sdc.toscaparser.api.parameters.Input;
+import org.openecomp.sdc.toscaparser.api.parameters.Output;
+import org.openecomp.sdc.toscaparser.api.prereq.CSAR;
+import org.openecomp.sdc.toscaparser.api.utils.JToscaErrorCodes;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.yaml.snakeyaml.Yaml;
+
+public class ToscaTemplate extends Object {
+
+	private static Logger log = LoggerFactory.getLogger(ToscaTemplate.class.getName());
+
+	// TOSCA template key names
+	private static final String DEFINITION_VERSION = "tosca_definitions_version"; 
+	private static final String DEFAULT_NAMESPACE = "tosca_default_namespace"; 
+	private static final String TEMPLATE_NAME = "template_name";
+	private static final String TOPOLOGY_TEMPLATE = "topology_template"; 
+	private static final String TEMPLATE_AUTHOR = "template_author"; 
+	private static final String TEMPLATE_VERSION = "template_version";
+	private static final String DESCRIPTION = "description"; 
+	private static final String IMPORTS = "imports";
+	private static final String DSL_DEFINITIONS = "dsl_definitions"; 
+	private static final String NODE_TYPES = "node_types";
+	private static final String RELATIONSHIP_TYPES = "relationship_types";
+	private static final String RELATIONSHIP_TEMPLATES = "relationship_templates";
+	private static final String CAPABILITY_TYPES = "capability_types";
+	private static final String ARTIFACT_TYPES = "artifact_types"; 
+	private static final String DATA_TYPES = "data_types";
+	private static final String INTERFACE_TYPES = "interface_types"; 
+	private static final String POLICY_TYPES = "policy_types"; 
+	private static final String GROUP_TYPES = "group_types"; 
+	private static final String REPOSITORIES = "repositories";
+	
+	private static String SECTIONS[] = {
+			DEFINITION_VERSION, DEFAULT_NAMESPACE, TEMPLATE_NAME,
+            TOPOLOGY_TEMPLATE, TEMPLATE_AUTHOR, TEMPLATE_VERSION,
+            DESCRIPTION, IMPORTS, DSL_DEFINITIONS, NODE_TYPES,
+            RELATIONSHIP_TYPES, RELATIONSHIP_TEMPLATES,
+            CAPABILITY_TYPES, ARTIFACT_TYPES, DATA_TYPES,
+            INTERFACE_TYPES, POLICY_TYPES, GROUP_TYPES, REPOSITORIES
+	};
+
+	// Sections that are specific to individual template definitions
+	private static final String METADATA = "metadata";
+	private static ArrayList<String> SPECIAL_SECTIONS;
+	
+    private ExtTools exttools = new ExtTools();
+
+    private ArrayList<String> VALID_TEMPLATE_VERSIONS;
+    private LinkedHashMap<String,ArrayList<String>> ADDITIONAL_SECTIONS;
+
+	private boolean isFile;
+	private String path;
+	private String inputPath;
+	private LinkedHashMap<String,Object> parsedParams;
+	private LinkedHashMap<String,Object> tpl;
+    private String version;
+    private ArrayList<Object> imports;
+    private LinkedHashMap<String,Object> relationshipTypes;
+    private Metadata metaData;
+    private String description;
+    private TopologyTemplate topologyTemplate;
+    private ArrayList<Repository> repositories;
+    private ArrayList<Input> inputs;
+    private ArrayList<RelationshipTemplate> relationshipTemplates;
+    private ArrayList<NodeTemplate> nodeTemplates;
+    private ArrayList<Output> outputs;
+	private ArrayList<Policy> policies;
+    private LinkedHashMap<String,Object> nestedToscaTplsWithTopology;
+    private ArrayList<TopologyTemplate> nestedToscaTemplatesWithTopology;
+    private ToscaGraph graph;
+    private String csarTempDir;
+    private int nestingLoopCounter;
+	private LinkedHashMap<String, LinkedHashMap<String, Object>> metaProperties;
+
+	@SuppressWarnings("unchecked")
+	public ToscaTemplate(String _path,
+			 			 LinkedHashMap<String,Object> _parsedParams,
+						 boolean aFile,
+						 LinkedHashMap<String,Object> yamlDictTpl) throws JToscaException {
+
+		ThreadLocalsHolder.setCollector(new ExceptionCollector(_path));
+
+		VALID_TEMPLATE_VERSIONS = new ArrayList<>();
+		VALID_TEMPLATE_VERSIONS.add("tosca_simple_yaml_1_0");
+	    VALID_TEMPLATE_VERSIONS.addAll(exttools.getVersions());
+		ADDITIONAL_SECTIONS = new LinkedHashMap<>();
+		SPECIAL_SECTIONS = new ArrayList<>();
+		SPECIAL_SECTIONS.add(METADATA);
+		ADDITIONAL_SECTIONS.put("tosca_simple_yaml_1_0",SPECIAL_SECTIONS);
+	    ADDITIONAL_SECTIONS.putAll(exttools.getSections());
+
+		//long startTime = System.nanoTime();
+		
+		
+		isFile = aFile;
+		inputPath = null;
+		path = null;
+		tpl = null;
+		csarTempDir = null;
+		nestedToscaTplsWithTopology = new LinkedHashMap<String,Object>(); 
+		nestedToscaTemplatesWithTopology = new ArrayList<TopologyTemplate>();
+
+		if(_path != null && !_path.isEmpty()) {
+			// save the original input path
+			inputPath = _path;
+			// get the actual path (will change with CSAR)
+			path = _getPath(_path);
+			// load the YAML template
+			if (path != null && !path.isEmpty()) {
+				try {
+					//System.out.println("Loading YAML file " + path);
+					log.debug("ToscaTemplate Loading YAMEL file {}", path);
+					InputStream input = new FileInputStream(new File(path));
+					Yaml yaml = new Yaml();
+					Object data = yaml.load(input);
+					this.tpl = (LinkedHashMap<String,Object>) data;
+				} 
+				catch (FileNotFoundException e) {
+					log.error("ToscaTemplate - Exception loading yaml: {}", e.getMessage());
+					return;
+				}
+				catch(Exception e) {
+					log.error("ToscaTemplate - Error loading yaml, aborting");
+					return;
+				}
+				
+		        if(yamlDictTpl != null) {
+		            //msg = (_('Both path and yaml_dict_tpl arguments were '
+		            //         'provided. Using path and ignoring yaml_dict_tpl.'))
+		            //log.info(msg)
+		            log.debug("ToscaTemplate - Both path and yaml_dict_tpl arguments were provided. Using path and ignoring yaml_dict_tpl");
+		        }
+			}
+			else {
+				// no input to process...
+				_abort();
+			}
+		} 
+		else {
+			if(yamlDictTpl != null) {
+                tpl = yamlDictTpl;
+			}
+            else {
+				ThreadLocalsHolder.getCollector().appendException(
+	                    "ValueError: No path or yaml_dict_tpl was provided. There is nothing to parse");
+				log.debug("ToscaTemplate ValueError: No path or yaml_dict_tpl was provided. There is nothing to parse");
+
+			}
+		}
+
+        if(tpl != null) {
+            parsedParams = _parsedParams;
+            _validateField();
+            this.version = _tplVersion();
+            this.metaData = _tplMetaData();
+            this.relationshipTypes = _tplRelationshipTypes();
+            this.description = _tplDescription();
+            this.topologyTemplate = _topologyTemplate();
+            this.repositories = _tplRepositories();
+            if(topologyTemplate.getTpl() != null) {
+                this.inputs = _inputs();
+                this.relationshipTemplates = _relationshipTemplates();
+                this.nodeTemplates = _nodeTemplates();
+                this.outputs = _outputs();
+                this.policies = _policies();
+                _handleNestedToscaTemplatesWithTopology();
+                graph = new ToscaGraph(nodeTemplates);
+            }
+        }
+
+        if(csarTempDir != null) {
+        	CSAR.deleteDir(new File(csarTempDir));
+        	csarTempDir = null;
+        }
+        
+		verifyTemplate();
+
+	}
+	
+	private void _abort() throws JToscaException {
+		// print out all exceptions caught
+		verifyTemplate();
+		throw new JToscaException("jtosca aborting", JToscaErrorCodes.PATH_NOT_VALID.getValue());
+	}
+	private TopologyTemplate _topologyTemplate() {
+		return new TopologyTemplate(
+				_tplTopologyTemplate(),
+				_getAllCustomDefs(imports),
+				relationshipTypes,
+				parsedParams,
+				null);
+	}
+
+	private ArrayList<Input> _inputs() {
+		return topologyTemplate.getInputs();
+	}
+
+	private ArrayList<NodeTemplate> _nodeTemplates() {
+		return topologyTemplate.getNodeTemplates();
+	}
+
+	private ArrayList<RelationshipTemplate> _relationshipTemplates() {
+		return topologyTemplate.getRelationshipTemplates();
+	}
+
+	private ArrayList<Output> _outputs() {
+		return topologyTemplate.getOutputs();
+	}
+
+	private String _tplVersion() {
+		return (String)tpl.get(DEFINITION_VERSION);
+	}
+
+	@SuppressWarnings("unchecked")
+	private Metadata _tplMetaData() {
+		Object mdo = tpl.get(METADATA);
+		if(mdo instanceof LinkedHashMap) {
+			return new Metadata((Map<String, Object>)mdo);
+		}
+		else {
+			return null;
+		}
+	}
+
+	private String _tplDescription() {
+		return (String)tpl.get(DESCRIPTION);
+	}
+
+	private ArrayList<Object> _tplImports() {
+		return (ArrayList<Object>)tpl.get(IMPORTS);
+	}
+
+	private ArrayList<Repository> _tplRepositories() {
+		LinkedHashMap<String,Object> repositories = 
+				(LinkedHashMap<String,Object>)tpl.get(REPOSITORIES);
+		ArrayList<Repository> reposit = new ArrayList<>();
+		if(repositories != null) {
+			for(Map.Entry<String,Object> me: repositories.entrySet()) {
+				Repository reposits = new Repository(me.getKey(),me.getValue());
+				reposit.add(reposits);
+			}
+		}
+		return reposit;
+	}
+
+	private LinkedHashMap<String,Object> _tplRelationshipTypes() {
+		return (LinkedHashMap<String,Object>)_getCustomTypes(RELATIONSHIP_TYPES,null);
+	}
+
+	@SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _tplRelationshipTemplates() {
+		return (LinkedHashMap<String,Object>)_tplTopologyTemplate().get(RELATIONSHIP_TEMPLATES);
+	}
+
+	@SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _tplTopologyTemplate() {
+		return (LinkedHashMap<String,Object>)tpl.get(TOPOLOGY_TEMPLATE);
+	}
+
+	private ArrayList<Policy> _policies() {
+		return topologyTemplate.getPolicies();
+	}
+	
+	private LinkedHashMap<String,Object> _getAllCustomDefs(ArrayList<Object> alImports) {
+		
+		String types[] = {
+			IMPORTS, NODE_TYPES, CAPABILITY_TYPES, RELATIONSHIP_TYPES, 
+			DATA_TYPES, INTERFACE_TYPES, POLICY_TYPES, GROUP_TYPES
+		};
+		LinkedHashMap<String,Object> customDefsFinal = new LinkedHashMap<String,Object>(); 
+		LinkedHashMap<String,Object> customDefs = _getCustomTypes(types,alImports);
+		if(customDefs != null) {
+			customDefsFinal.putAll(customDefs);
+			if(customDefs.get(IMPORTS) != null) {
+				@SuppressWarnings("unchecked")
+				LinkedHashMap<String,Object> importDefs = _getAllCustomDefs((ArrayList<Object>)customDefs.get(IMPORTS));
+				customDefsFinal.putAll(importDefs);
+			}
+		}
+		
+        // As imports are not custom_types, remove from the dict
+        customDefsFinal.remove(IMPORTS);
+
+		return customDefsFinal;
+	}
+
+	@SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _getCustomTypes(Object typeDefinitions,ArrayList<Object> alImports) {
+		
+        // Handle custom types defined in imported template files
+        // This method loads the custom type definitions referenced in "imports"
+        // section of the TOSCA YAML template.
+		
+		LinkedHashMap<String,Object> customDefs = new LinkedHashMap<String,Object>();
+        ArrayList<String> typeDefs = new ArrayList<String>();
+        if(typeDefinitions  instanceof String[]) {
+        	for(String s: (String[])typeDefinitions) {
+        		typeDefs.add(s);
+        	}
+        }
+        else {
+        	typeDefs.add((String)typeDefinitions);
+        }
+
+        if(alImports == null) {
+            alImports = _tplImports();
+        }
+
+        if(alImports != null) {
+        	ImportsLoader customService = new ImportsLoader(alImports,path,typeDefs,tpl);
+        	ArrayList<LinkedHashMap<String,Object>> nestedToscaTpls = customService.getNestedToscaTpls();
+        	_updateNestedToscaTplsWithTopology(nestedToscaTpls);
+
+        	customDefs = customService.getCustomDefs();
+        	if(customDefs == null) {
+        		return null;
+        	}
+        }
+
+        //Handle custom types defined in current template file
+        for(String td: typeDefs) {
+        	if(!td.equals(IMPORTS)) {
+        		LinkedHashMap<String,Object>  innerCustomTypes = (LinkedHashMap<String,Object> )tpl.get(td);
+        		if(innerCustomTypes != null) {
+        			customDefs.putAll(innerCustomTypes);
+        		}
+        	}
+        }
+        return customDefs;
+	}
+
+	private void _updateNestedToscaTplsWithTopology(ArrayList<LinkedHashMap<String,Object>> nestedToscaTpls) {
+		for(LinkedHashMap<String,Object> ntpl: nestedToscaTpls) {
+			// there is just one key:value pair in ntpl
+			for(Map.Entry<String,Object> me: ntpl.entrySet()) {
+				String fileName = me.getKey();
+				@SuppressWarnings("unchecked")
+				LinkedHashMap<String,Object> toscaTpl = (LinkedHashMap<String,Object>)me.getValue();
+				if(toscaTpl.get(TOPOLOGY_TEMPLATE) != null) {
+					if(nestedToscaTplsWithTopology.get(fileName) == null) {
+						nestedToscaTplsWithTopology.putAll(ntpl);
+					}
+				}
+			}
+		}
+	}
+
+	// **experimental** (multi level nesting) RECURSIVE - BEWARE OF INIFINITE LOOPS...
+	private void _handleNestedToscaTemplatesWithTopology2(TopologyTemplate tt) {
+		if(++nestingLoopCounter > 10) {
+			log.error("ToscaTemplate - _handleNestedToscaTemplatesWithTopology2 - Nested Topologies Loop: too many levels, aborting");
+			return;
+		}
+		for(Map.Entry<String,Object> me: nestedToscaTplsWithTopology.entrySet()) {
+			String fname = me.getKey();
+			LinkedHashMap<String,Object> toscaTpl = 
+							(LinkedHashMap<String,Object>)me.getValue();
+			for(NodeTemplate nt: tt.getNodeTemplates()) {
+				if(_isSubMappedNode2(nt,toscaTpl)) {
+					parsedParams = _getParamsForNestedTemplate(nt);
+					LinkedHashMap<String,Object> topologyTpl = 
+							(LinkedHashMap<String,Object>)toscaTpl.get(TOPOLOGY_TEMPLATE);
+					TopologyTemplate topologyWithSubMapping = 
+						new TopologyTemplate(topologyTpl,
+											 _getAllCustomDefs(null), 
+											 relationshipTypes, 
+											 parsedParams,
+											 nt);
+					if(topologyWithSubMapping.getSubstitutionMappings() != null) {
+                        // Record nested topology templates in top level template
+                        //nestedToscaTemplatesWithTopology.add(topologyWithSubMapping);
+                        // Set substitution mapping object for mapped node
+                        nt.setSubMappingToscaTemplate2(
+                        		topologyWithSubMapping.getSubstitutionMappings());
+                        _handleNestedToscaTemplatesWithTopology2(topologyWithSubMapping);
+					}
+				}
+			}
+		}
+	}
+	
+	private void _handleNestedToscaTemplatesWithTopology() {
+		for(Map.Entry<String,Object> me: nestedToscaTplsWithTopology.entrySet()) {
+			String fname = me.getKey();
+			LinkedHashMap<String,Object> toscaTpl = 
+							(LinkedHashMap<String,Object>)me.getValue();
+			for(NodeTemplate nt: nodeTemplates) {
+				if(_isSubMappedNode(nt,toscaTpl)) {
+					parsedParams = _getParamsForNestedTemplate(nt);
+                    ArrayList<Object> alim = (ArrayList<Object>)toscaTpl.get(IMPORTS);
+					LinkedHashMap<String,Object> topologyTpl = 
+							(LinkedHashMap<String,Object>)toscaTpl.get(TOPOLOGY_TEMPLATE);
+					TopologyTemplate topologyWithSubMapping = 
+							new TopologyTemplate(topologyTpl,
+												//_getAllCustomDefs(null),
+												_getAllCustomDefs(alim),
+												relationshipTypes, 
+												parsedParams,
+												nt);
+					if(topologyWithSubMapping.getSubstitutionMappings() != null) {
+                        // Record nested topology templates in top level template
+                        nestedToscaTemplatesWithTopology.add(topologyWithSubMapping);
+                        // Set substitution mapping object for mapped node
+                        nt.setSubMappingToscaTemplate(
+                        		topologyWithSubMapping.getSubstitutionMappings());
+					}
+				}
+			}
+		}
+	}
+
+	private void _validateField() {
+		String sVersion = _tplVersion();
+		if(sVersion == null) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+					"MissingRequiredField: Template is missing required field \"%s\"",DEFINITION_VERSION));
+		}
+		else {
+			_validateVersion(sVersion);
+			this.version = sVersion;
+		}
+		
+		for (String sKey : tpl.keySet()) {
+			boolean bFound = false;
+			for (String sSection: SECTIONS) {
+				if(sKey.equals(sSection)) {
+					bFound = true;
+					break;
+				}
+			}
+			// check ADDITIONAL_SECTIONS
+			if(!bFound) {
+				if(ADDITIONAL_SECTIONS.get(version) != null &&
+						ADDITIONAL_SECTIONS.get(version).contains(sKey)) {
+					bFound = true;
+				}
+			}
+			if(!bFound) {
+				ThreadLocalsHolder.getCollector().appendException(String.format(
+						"UnknownFieldError: Template contains unknown field \"%s\"",
+						sKey));
+			}
+		}
+	}
+
+	private void _validateVersion(String sVersion) {
+		boolean bFound = false;
+		for(String vtv: VALID_TEMPLATE_VERSIONS) {
+			if(sVersion.equals(vtv)) {
+				bFound = true;
+				break;
+			}
+		}
+		if(!bFound) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+				"InvalidTemplateVersion: \"%s\" is invalid. Valid versions are %s",
+				sVersion,VALID_TEMPLATE_VERSIONS.toString()));
+		}
+		else if(!sVersion.equals("tosca_simple_yaml_1_0")) {
+			EntityType.updateDefinitions(sVersion);
+		}
+	}
+
+	private String _getPath(String _path) throws JToscaException {
+		if (_path.toLowerCase().endsWith(".yaml") || _path.toLowerCase().endsWith(".yml")) {
+			return _path;
+		} 
+		else if (_path.toLowerCase().endsWith(".zip") || _path.toLowerCase().endsWith(".csar")) {
+			// a CSAR archive
+			CSAR csar = new CSAR(_path, isFile);
+			if (csar.validate()) {
+				try {
+					csar.decompress();
+					metaProperties = csar.getMetaProperties();
+				} 
+				catch (IOException e) {
+					log.error("ToscaTemplate - _getPath - IOException trying to decompress {}", _path);
+					return null;
+				}
+				isFile = true; // the file has been decompressed locally
+				csar.cleanup();
+				csarTempDir = csar.getTempDir();
+				return csar.getTempDir() + File.separator + csar.getMainTemplate();
+			}
+		} 
+		else {
+			ThreadLocalsHolder.getCollector().appendException("ValueError: " + _path + " is not a valid file");
+			return null;
+		}
+		return null;
+	}
+
+	private void verifyTemplate() throws JToscaException {
+		ThreadLocalsHolder.getCollector().setWantTrace(false);
+
+		//Warnings
+		int warningsCount = ThreadLocalsHolder.getCollector().warningsCaught();
+		if (warningsCount > 0) {
+			List<String> warningsStrings = ThreadLocalsHolder.getCollector().getWarningsReport();
+			log.warn("####################################################################################################");
+			log.warn("CSAR Warnings found! CSAR name - {}", inputPath);
+			log.warn("ToscaTemplate - verifyTemplate - {} Parsing Warning{} occurred...", warningsCount, (warningsCount > 1 ? "s" : ""));
+			for (String s : warningsStrings) {
+				log.warn("{}. CSAR name - {}", s, inputPath);
+			}
+			log.warn("####################################################################################################");
+		}
+
+		//Criticals
+		int criticalsCount = ThreadLocalsHolder.getCollector().criticalsCaught();
+		if (criticalsCount > 0) {
+			List<String> criticalStrings = ThreadLocalsHolder.getCollector().getCriticalsReport();
+			log.error("####################################################################################################");
+			log.error("ToscaTemplate - verifyTemplate - {} Parsing Critical{} occurred...", criticalsCount, (criticalsCount > 1 ? "s" : ""));
+			for (String s : criticalStrings) {
+				log.error("{}. CSAR name - {}", s, inputPath);
+			}
+			throw new JToscaException(String.format("CSAR Validation Failed. CSAR name - {}. Please check logs for details.", inputPath), JToscaErrorCodes.CSAR_TOSCA_VALIDATION_ERROR.getValue());
+		}
+	}
+
+	public String getPath() {
+		return path;
+	}
+
+	public String getVersion() {
+		return version;
+	}
+	
+	public String getDescription() {
+		return description;
+	}
+	
+	public TopologyTemplate getTopologyTemplate() {
+		return topologyTemplate;
+	}
+	
+	public Metadata getMetaData() {
+		return metaData;
+	}
+	
+	public ArrayList<Input> getInputs() {
+		return inputs;
+	}
+	
+	public ArrayList<Output> getOutputs() {
+		return outputs;
+	}
+	
+	public ArrayList<Policy> getPolicies() {
+		return policies;
+	}
+	
+	public ArrayList<NodeTemplate> getNodeTemplates() {
+		return nodeTemplates;
+	}
+
+	public LinkedHashMap<String, Object> getMetaProperties(String propertiesFile) {
+		return metaProperties.get(propertiesFile);
+	}
+	
+	private boolean _isSubMappedNode(NodeTemplate nt,LinkedHashMap<String,Object> toscaTpl) {
+		// Return True if the nodetemple is substituted
+		if(nt != null && nt.getSubMappingToscaTemplate() == null &&
+				getSubMappingNodeType(toscaTpl).equals(nt.getType()) &&
+				nt.getInterfaces().size() < 1) {
+			return true;
+		}
+		return false;
+	}
+
+	private boolean _isSubMappedNode2(NodeTemplate nt,LinkedHashMap<String,Object> toscaTpl) {
+		// Return True if the nodetemple is substituted
+		if(nt != null && nt.getSubMappingToscaTemplate2() == null &&
+				getSubMappingNodeType(toscaTpl).equals(nt.getType()) &&
+				nt.getInterfaces().size() < 1) {
+			return true;
+		}
+		return false;
+	}
+
+	private LinkedHashMap<String,Object> _getParamsForNestedTemplate(NodeTemplate nt) {
+		// Return total params for nested_template
+		LinkedHashMap<String,Object> pparams;
+		if(parsedParams != null) {
+			pparams = parsedParams;
+		}
+		else {
+			pparams = new LinkedHashMap<String,Object>();
+		}
+		if(nt != null) {
+			for(String pname: nt.getProperties().keySet()) {
+				pparams.put(pname,nt.getPropertyValue(pname));
+			}
+		}
+		return pparams;
+	}
+
+	private String getSubMappingNodeType(LinkedHashMap<String,Object> toscaTpl) {
+		// Return substitution mappings node type
+		if(toscaTpl != null) {
+			return TopologyTemplate.getSubMappingNodeType(
+					(LinkedHashMap<String,Object>)toscaTpl.get(TOPOLOGY_TEMPLATE));
+		}
+		return null;
+	}
+
+	private boolean _hasSubstitutionMapping() {
+        // Return True if the template has valid substitution mappings
+        return topologyTemplate != null &&
+            topologyTemplate.getSubstitutionMappings() != null;
+	}
+
+	public boolean hasNestedTemplates() {
+        // Return True if the tosca template has nested templates
+        return nestedToscaTemplatesWithTopology != null &&
+        		nestedToscaTemplatesWithTopology.size() >= 1;
+		
+	}
+	
+	public ArrayList<TopologyTemplate> getNestedTemplates() {
+		return nestedToscaTemplatesWithTopology;
+	}
+
+	@Override
+	public String toString() {
+		return "ToscaTemplate{" +
+				"exttools=" + exttools +
+				", VALID_TEMPLATE_VERSIONS=" + VALID_TEMPLATE_VERSIONS +
+				", ADDITIONAL_SECTIONS=" + ADDITIONAL_SECTIONS +
+				", isFile=" + isFile +
+				", path='" + path + '\'' +
+				", inputPath='" + inputPath + '\'' +
+				", parsedParams=" + parsedParams +
+				", tpl=" + tpl +
+				", version='" + version + '\'' +
+				", imports=" + imports +
+				", relationshipTypes=" + relationshipTypes +
+				", metaData=" + metaData +
+				", description='" + description + '\'' +
+				", topologyTemplate=" + topologyTemplate +
+				", repositories=" + repositories +
+				", inputs=" + inputs +
+				", relationshipTemplates=" + relationshipTemplates +
+				", nodeTemplates=" + nodeTemplates +
+				", outputs=" + outputs +
+				", policies=" + policies +
+				", nestedToscaTplsWithTopology=" + nestedToscaTplsWithTopology +
+				", nestedToscaTemplatesWithTopology=" + nestedToscaTemplatesWithTopology +
+				", graph=" + graph +
+				", csarTempDir='" + csarTempDir + '\'' +
+				", nestingLoopCounter=" + nestingLoopCounter +
+				'}';
+	}
+}
+
+/*python
+
+import logging
+import os
+
+from copy import deepcopy
+from toscaparser.common.exception import ExceptionCollector.collector
+from toscaparser.common.exception import InvalidTemplateVersion
+from toscaparser.common.exception import MissingRequiredFieldError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.common.exception import ValidationError
+from toscaparser.elements.entity_type import update_definitions
+from toscaparser.extensions.exttools import ExtTools
+import org.openecomp.sdc.toscaparser.api.imports
+from toscaparser.prereq.csar import CSAR
+from toscaparser.repositories import Repository
+from toscaparser.topology_template import TopologyTemplate
+from toscaparser.tpl_relationship_graph import ToscaGraph
+from toscaparser.utils.gettextutils import _
+import org.openecomp.sdc.toscaparser.api.utils.yamlparser
+
+
+# TOSCA template key names
+SECTIONS = (DEFINITION_VERSION, DEFAULT_NAMESPACE, TEMPLATE_NAME,
+            TOPOLOGY_TEMPLATE, TEMPLATE_AUTHOR, TEMPLATE_VERSION,
+            DESCRIPTION, IMPORTS, DSL_DEFINITIONS, NODE_TYPES,
+            RELATIONSHIP_TYPES, RELATIONSHIP_TEMPLATES,
+            CAPABILITY_TYPES, ARTIFACT_TYPES, DATA_TYPES, INTERFACE_TYPES,
+            POLICY_TYPES, GROUP_TYPES, REPOSITORIES) = \
+           ('tosca_definitions_version', 'tosca_default_namespace',
+            'template_name', 'topology_template', 'template_author',
+            'template_version', 'description', 'imports', 'dsl_definitions',
+            'node_types', 'relationship_types', 'relationship_templates',
+            'capability_types', 'artifact_types', 'data_types',
+            'interface_types', 'policy_types', 'group_types', 'repositories')
+# Sections that are specific to individual template definitions
+SPECIAL_SECTIONS = (METADATA) = ('metadata')
+
+log = logging.getLogger("tosca.model")
+
+YAML_LOADER = toscaparser.utils.yamlparser.load_yaml
+
+
+class ToscaTemplate(object):
+    exttools = ExtTools()
+
+    VALID_TEMPLATE_VERSIONS = ['tosca_simple_yaml_1_0']
+
+    VALID_TEMPLATE_VERSIONS.extend(exttools.get_versions())
+
+    ADDITIONAL_SECTIONS = {'tosca_simple_yaml_1_0': SPECIAL_SECTIONS}
+
+    ADDITIONAL_SECTIONS.update(exttools.get_sections())
+
+    '''Load the template data.'''
+    def __init__(self, path=None, parsed_params=None, a_file=True,
+                 yaml_dict_tpl=None):
+
+        ExceptionCollector.collector.start()
+        self.a_file = a_file
+        self.input_path = None
+        self.path = None
+        self.tpl = None
+        self.nested_tosca_tpls_with_topology = {}
+        self.nested_tosca_templates_with_topology = []
+        if path:
+            self.input_path = path
+            self.path = self._get_path(path)
+            if self.path:
+                self.tpl = YAML_LOADER(self.path, self.a_file)
+            if yaml_dict_tpl:
+                msg = (_('Both path and yaml_dict_tpl arguments were '
+                         'provided. Using path and ignoring yaml_dict_tpl.'))
+                log.info(msg)
+                print(msg)
+        else:
+            if yaml_dict_tpl:
+                self.tpl = yaml_dict_tpl
+            else:
+                ExceptionCollector.collector.appendException(
+                    ValueError(_('No path or yaml_dict_tpl was provided. '
+                                 'There is nothing to parse.')))
+
+        if self.tpl:
+            self.parsed_params = parsed_params
+            self._validate_field()
+            self.version = self._tpl_version()
+            self.relationship_types = self._tpl_relationship_types()
+            self.description = self._tpl_description()
+            self.topology_template = self._topology_template()
+            self.repositories = self._tpl_repositories()
+            if self.topology_template.tpl:
+                self.inputs = self._inputs()
+                self.relationship_templates = self._relationship_templates()
+                self.nodetemplates = self._nodetemplates()
+                self.outputs = self._outputs()
+                self._handle_nested_tosca_templates_with_topology()
+                self.graph = ToscaGraph(self.nodetemplates)
+
+        ExceptionCollector.collector.stop()
+        self.verify_template()
+
+    def _topology_template(self):
+        return TopologyTemplate(self._tpl_topology_template(),
+                                self._get_all_custom_defs(),
+                                self.relationship_types,
+                                self.parsed_params,
+                                None)
+
+    def _inputs(self):
+        return self.topology_template.inputs
+
+    def _nodetemplates(self):
+        return self.topology_template.nodetemplates
+
+    def _relationship_templates(self):
+        return self.topology_template.relationship_templates
+
+    def _outputs(self):
+        return self.topology_template.outputs
+
+    def _tpl_version(self):
+        return self.tpl.get(DEFINITION_VERSION)
+
+    def _tpl_description(self):
+        desc = self.tpl.get(DESCRIPTION)
+        if desc:
+            return desc.rstrip()
+
+    def _tpl_imports(self):
+        return self.tpl.get(IMPORTS)
+
+    def _tpl_repositories(self):
+        repositories = self.tpl.get(REPOSITORIES)
+        reposit = []
+        if repositories:
+            for name, val in repositories.items():
+                reposits = Repository(name, val)
+                reposit.append(reposits)
+        return reposit
+
+    def _tpl_relationship_types(self):
+        return self._get_custom_types(RELATIONSHIP_TYPES)
+
+    def _tpl_relationship_templates(self):
+        topology_template = self._tpl_topology_template()
+        return topology_template.get(RELATIONSHIP_TEMPLATES)
+
+    def _tpl_topology_template(self):
+        return self.tpl.get(TOPOLOGY_TEMPLATE)
+
+    def _get_all_custom_defs(self, imports=None):
+        types = [IMPORTS, NODE_TYPES, CAPABILITY_TYPES, RELATIONSHIP_TYPES,
+                 DATA_TYPES, INTERFACE_TYPES, POLICY_TYPES, GROUP_TYPES]
+        custom_defs_final = {}
+        custom_defs = self._get_custom_types(types, imports)
+        if custom_defs:
+            custom_defs_final.update(custom_defs)
+            if custom_defs.get(IMPORTS):
+                import_defs = self._get_all_custom_defs(
+                    custom_defs.get(IMPORTS))
+                custom_defs_final.update(import_defs)
+
+        # As imports are not custom_types, removing from the dict
+        custom_defs_final.pop(IMPORTS, None)
+        return custom_defs_final
+
+    def _get_custom_types(self, type_definitions, imports=None):
+        """Handle custom types defined in imported template files
+
+        This method loads the custom type definitions referenced in "imports"
+        section of the TOSCA YAML template.
+        """
+        custom_defs = {}
+        type_defs = []
+        if not isinstance(type_definitions, list):
+            type_defs.append(type_definitions)
+        else:
+            type_defs = type_definitions
+
+        if not imports:
+            imports = self._tpl_imports()
+
+        if imports:
+            custom_service = toscaparser.imports.\
+                ImportsLoader(imports, self.path,
+                              type_defs, self.tpl)
+
+            nested_tosca_tpls = custom_service.get_nested_tosca_tpls()
+            self._update_nested_tosca_tpls_with_topology(nested_tosca_tpls)
+
+            custom_defs = custom_service.get_custom_defs()
+            if not custom_defs:
+                return
+
+        # Handle custom types defined in current template file
+        for type_def in type_defs:
+            if type_def != IMPORTS:
+                inner_custom_types = self.tpl.get(type_def) or {}
+                if inner_custom_types:
+                    custom_defs.update(inner_custom_types)
+        return custom_defs
+
+    def _update_nested_tosca_tpls_with_topology(self, nested_tosca_tpls):
+        for tpl in nested_tosca_tpls:
+            filename, tosca_tpl = list(tpl.items())[0]
+            if (tosca_tpl.get(TOPOLOGY_TEMPLATE) and
+                filename not in list(
+                    self.nested_tosca_tpls_with_topology.keys())):
+                self.nested_tosca_tpls_with_topology.update(tpl)
+
+    def _handle_nested_tosca_templates_with_topology(self):
+        for fname, tosca_tpl in self.nested_tosca_tpls_with_topology.items():
+            for nodetemplate in self.nodetemplates:
+                if self._is_sub_mapped_node(nodetemplate, tosca_tpl):
+                    parsed_params = self._get_params_for_nested_template(
+                        nodetemplate)
+                    topology_tpl = tosca_tpl.get(TOPOLOGY_TEMPLATE)
+                    topology_with_sub_mapping = TopologyTemplate(
+                        topology_tpl,
+                        self._get_all_custom_defs(),
+                        self.relationship_types,
+                        parsed_params,
+                        nodetemplate)
+                    if topology_with_sub_mapping.substitution_mappings:
+                        # Record nested topo templates in top level template
+                        self.nested_tosca_templates_with_topology.\
+                            append(topology_with_sub_mapping)
+                        # Set substitution mapping object for mapped node
+                        nodetemplate.sub_mapping_tosca_template = \
+                            topology_with_sub_mapping.substitution_mappings
+
+    def _validate_field(self):
+        version = self._tpl_version()
+        if not version:
+            ExceptionCollector.collector.appendException(
+                MissingRequiredFieldError(what='Template',
+                                          required=DEFINITION_VERSION))
+        else:
+            self._validate_version(version)
+            self.version = version
+
+        for name in self.tpl:
+            if (name not in SECTIONS and
+               name not in self.ADDITIONAL_SECTIONS.get(version, ())):
+                ExceptionCollector.collector.appendException(
+                    UnknownFieldError(what='Template', field=name))
+
+    def _validate_version(self, version):
+        if version not in self.VALID_TEMPLATE_VERSIONS:
+            ExceptionCollector.collector.appendException(
+                InvalidTemplateVersion(
+                    what=version,
+                    valid_versions=', '. join(self.VALID_TEMPLATE_VERSIONS)))
+        else:
+            if version != 'tosca_simple_yaml_1_0':
+                update_definitions(version)
+
+    def _get_path(self, path):
+        if path.lower().endswith(('.yaml','.yml')):
+            return path
+        elif path.lower().endswith(('.zip', '.csar')):
+            # a CSAR archive
+            csar = CSAR(path, self.a_file)
+            if csar.validate():
+                csar.decompress()
+                self.a_file = True  # the file has been decompressed locally
+                return os.path.join(csar.temp_dir, csar.get_main_template())
+        else:
+            ExceptionCollector.collector.appendException(
+                ValueError(_('"%(path)s" is not a valid file.')
+                           % {'path': path}))
+
+    def verify_template(self):
+        if ExceptionCollector.collector.exceptionsCaught():
+            if self.input_path:
+                raise ValidationError(
+                    message=(_('\nThe input "%(path)s" failed validation with '
+                               'the following error(s): \n\n\t')
+                             % {'path': self.input_path}) +
+                    '\n\t'.join(ExceptionCollector.collector.getExceptionsReport()))
+            else:
+                raise ValidationError(
+                    message=_('\nThe pre-parsed input failed validation with '
+                              'the following error(s): \n\n\t') +
+                    '\n\t'.join(ExceptionCollector.collector.getExceptionsReport()))
+        else:
+            if self.input_path:
+                msg = (_('The input "%(path)s" successfully passed '
+                         'validation.') % {'path': self.input_path})
+            else:
+                msg = _('The pre-parsed input successfully passed validation.')
+
+            log.info(msg)
+
+    def _is_sub_mapped_node(self, nodetemplate, tosca_tpl):
+        """Return True if the nodetemple is substituted."""
+        if (nodetemplate and not nodetemplate.sub_mapping_tosca_template and
+                self.get_sub_mapping_node_type(tosca_tpl) == nodetemplate.type
+                and len(nodetemplate.interfaces) < 1):
+            return True
+        else:
+            return False
+
+    def _get_params_for_nested_template(self, nodetemplate):
+        """Return total params for nested_template."""
+        parsed_params = deepcopy(self.parsed_params) \
+            if self.parsed_params else {}
+        if nodetemplate:
+            for pname in nodetemplate.get_properties():
+                parsed_params.update({pname:
+                                      nodetemplate.get_property_value(pname)})
+        return parsed_params
+
+    def get_sub_mapping_node_type(self, tosca_tpl):
+        """Return substitution mappings node type."""
+        if tosca_tpl:
+            return TopologyTemplate.get_sub_mapping_node_type(
+                tosca_tpl.get(TOPOLOGY_TEMPLATE))
+
+    def _has_substitution_mappings(self):
+        """Return True if the template has valid substitution mappings."""
+        return self.topology_template is not None and \
+            self.topology_template.substitution_mappings is not None
+
+    def has_nested_templates(self):
+        """Return True if the tosca template has nested templates."""
+        return self.nested_tosca_templates_with_topology is not None and \
+            len(self.nested_tosca_templates_with_topology) >= 1
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/Triggers.java b/src/main/java/org/openecomp/sdc/toscaparser/api/Triggers.java
new file mode 100644
index 0000000..0ec0b5a
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/Triggers.java
@@ -0,0 +1,183 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.openecomp.sdc.toscaparser.api.utils.ValidateUtils;
+
+public class Triggers extends EntityTemplate {
+
+	private static final String DESCRIPTION = "description";
+	private static final String EVENT = "event_type";
+	private static final String SCHEDULE = "schedule";
+	private static final String TARGET_FILTER = "target_filter";
+	private static final String CONDITION = "condition";
+	private static final String ACTION = "action";
+
+	private static final String SECTIONS[] = {
+		DESCRIPTION, EVENT, SCHEDULE, TARGET_FILTER, CONDITION, ACTION
+	};
+
+	private static final String METER_NAME = "meter_name";
+	private static final String CONSTRAINT = "constraint";
+	private static final String PERIOD = "period";
+	private static final String EVALUATIONS = "evaluations";
+	private static final String METHOD = "method";
+	private static final String THRESHOLD = "threshold";
+	private static final String COMPARISON_OPERATOR = "comparison_operator";
+	
+	private static final String CONDITION_KEYNAMES[] = {
+		METER_NAME,	CONSTRAINT, PERIOD, EVALUATIONS, METHOD, THRESHOLD, COMPARISON_OPERATOR
+	};
+
+	private String name;
+	private LinkedHashMap<String,Object> triggerTpl;
+
+	public Triggers(String _name,LinkedHashMap<String,Object> _triggerTpl) {
+		super(); // dummy. don't want super
+	    name = _name;
+	    triggerTpl = _triggerTpl;
+	    _validateKeys();
+	    _validateCondition();
+	    _validateInput();
+	}
+
+	public String getDescription() {
+		return (String)triggerTpl.get("description");
+	}
+
+	public String getEvent() {
+		return (String)triggerTpl.get("event_type");
+	}
+ 
+	public LinkedHashMap<String,Object> getSchedule() {
+		return (LinkedHashMap<String,Object>)triggerTpl.get("schedule");
+	}
+ 
+	public LinkedHashMap<String,Object> getTargetFilter() {
+		return (LinkedHashMap<String,Object>)triggerTpl.get("target_filter");
+	}
+ 
+	public LinkedHashMap<String,Object> getCondition() {
+		return (LinkedHashMap<String,Object>)triggerTpl.get("condition");
+	}
+ 
+	public LinkedHashMap<String,Object> getAction() {
+		return (LinkedHashMap<String,Object>)triggerTpl.get("action");
+	}
+ 
+	private void _validateKeys() {	
+		for(String key: triggerTpl.keySet()) {
+			boolean bFound = false;
+			for(int i=0; i<SECTIONS.length; i++) {
+				if(key.equals(SECTIONS[i])) {
+					bFound = true;
+					break;
+				}
+			}
+			if(!bFound) {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                    "UnknownFieldError: Triggers \"%s\" contains unknown field \"%s\"",
+	                    name,key));
+			}
+		}
+	}
+
+	private void _validateCondition() {	
+		for(String key: getCondition().keySet()) {
+			boolean bFound = false;
+			for(int i=0; i<CONDITION_KEYNAMES.length; i++) {
+				if(key.equals(CONDITION_KEYNAMES[i])) {
+					bFound = true;
+					break;
+				}
+			}
+			if(!bFound) {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                    "UnknownFieldError: Triggers \"%s\" contains unknown field \"%s\"",
+	                    name,key));
+			}
+		}
+	}
+	
+	private void _validateInput() {
+		for(String key: getCondition().keySet()) {
+			Object value = getCondition().get(key);
+			if(key.equals(PERIOD) || key.equals(EVALUATIONS)) {
+				ValidateUtils.validateInteger(value);
+			}
+			else if(key.equals(THRESHOLD)) {
+				ValidateUtils.validateNumeric(value);
+			}
+			else if(key.equals(METER_NAME) || key.equals(METHOD)) {
+				ValidateUtils.validateString(value);
+			}
+		}
+	}
+
+	@Override
+	public String toString() {
+		return "Triggers{" +
+				"name='" + name + '\'' +
+				", triggerTpl=" + triggerTpl +
+				'}';
+	}
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.entity_template import EntityTemplate
+
+SECTIONS = (DESCRIPTION, EVENT, SCHEDULE, TARGET_FILTER, CONDITION, ACTION) = \
+           ('description', 'event_type', 'schedule',
+            'target_filter', 'condition', 'action')
+CONDITION_KEYNAMES = (CONTRAINT, PERIOD, EVALUATIONS, METHOD) = \
+                     ('constraint', 'period', 'evaluations', 'method')
+log = logging.getLogger('tosca')
+
+
+class Triggers(EntityTemplate):
+
+    '''Triggers defined in policies of topology template'''
+
+    def __init__(self, name, trigger_tpl):
+        self.name = name
+        self.trigger_tpl = trigger_tpl
+        self._validate_keys()
+        self._validate_condition()
+
+    def get_description(self):
+        return self.trigger_tpl['description']
+
+    def get_event(self):
+        return self.trigger_tpl['event_type']
+
+    def get_schedule(self):
+        return self.trigger_tpl['schedule']
+
+    def get_target_filter(self):
+        return self.trigger_tpl['target_filter']
+
+    def get_condition(self):
+        return self.trigger_tpl['condition']
+
+    def get_action(self):
+        return self.trigger_tpl['action']
+
+    def _validate_keys(self):
+        for key in self.trigger_tpl.keys():
+            if key not in SECTIONS:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Triggers "%s"' % self.name,
+                                      field=key))
+
+    def _validate_condition(self):
+        for key in self.get_condition():
+            if key not in CONDITION_KEYNAMES:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Triggers "%s"' % self.name,
+                                      field=key))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/UnsupportedType.java b/src/main/java/org/openecomp/sdc/toscaparser/api/UnsupportedType.java
new file mode 100644
index 0000000..2bd0197
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/UnsupportedType.java
@@ -0,0 +1,78 @@
+package org.openecomp.sdc.toscaparser.api;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class UnsupportedType {
+
+    // Note: TOSCA spec version related
+
+	/*
+    The tosca.nodes.Storage.ObjectStorage and tosca.nodes.Storage.BlockStorage
+    used here as un_supported_types are part of the name changes in TOSCA spec
+    version 1.1. The original name as specified in version 1.0 are,
+    tosca.nodes.BlockStorage and tosca.nodes.ObjectStorage which are supported
+    by the tosca-parser. Since there are little overlapping in version support
+    currently in the tosca-parser, the names tosca.nodes.Storage.ObjectStorage
+    and tosca.nodes.Storage.BlockStorage are used here to demonstrate the usage
+    of un_supported_types. As tosca-parser move to provide support for version
+    1.1 and higher, they will be removed.
+    */
+	
+    private static final String unsupportedTypes[] = {
+    									"tosca.test.invalidtype",
+    									"tosca.nodes.Storage.ObjectStorage",
+    									"tosca.nodes.Storage.BlockStorage"};
+
+    public static boolean validateType(String entityType) {
+    	for(String ust: unsupportedTypes) {
+    		if(ust.equals(entityType)) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"UnsupportedTypeError: Entity type \"%s\" is not supported",entityType));
+    			return true;
+    		}
+    	}
+        return false;
+    }
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import UnsupportedTypeError
+from toscaparser.utils.gettextutils import _
+
+log = logging.getLogger('tosca')
+
+
+class UnsupportedType(object):
+
+    """Note: TOSCA spec version related
+
+    The tosca.nodes.Storage.ObjectStorage and tosca.nodes.Storage.BlockStorage
+    used here as un_supported_types are part of the name changes in TOSCA spec
+    version 1.1. The original name as specified in version 1.0 are,
+    tosca.nodes.BlockStorage and tosca.nodes.ObjectStorage which are supported
+    by the tosca-parser. Since there are little overlapping in version support
+    currently in the tosca-parser, the names tosca.nodes.Storage.ObjectStorage
+    and tosca.nodes.Storage.BlockStorage are used here to demonstrate the usage
+    of un_supported_types. As tosca-parser move to provide support for version
+    1.1 and higher, they will be removed.
+    """
+    un_supported_types = ['tosca.test.invalidtype',
+                          'tosca.nodes.Storage.ObjectStorage',
+                          'tosca.nodes.Storage.BlockStorage']
+
+    def __init__(self):
+        pass
+
+    @staticmethod
+    def validate_type(entitytype):
+        if entitytype in UnsupportedType.un_supported_types:
+            ExceptionCollector.appendException(UnsupportedTypeError(
+                                               what=_('%s')
+                                               % entitytype))
+            return True
+        else:
+            return False
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/common/ExceptionCollector.java b/src/main/java/org/openecomp/sdc/toscaparser/api/common/ExceptionCollector.java
new file mode 100644
index 0000000..fa65ae4
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/common/ExceptionCollector.java
@@ -0,0 +1,122 @@
+package org.openecomp.sdc.toscaparser.api.common;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+// Perfectly good enough... 
+
+public class ExceptionCollector {
+
+    private static Logger log = LoggerFactory.getLogger(ExceptionCollector.class.getName());
+
+    private Map<String, String> notAnalyzedExceptions = new HashMap<>();
+    private Map<String, String> criticalExceptions = new HashMap<>();
+    private Map<String, String> warningExceptions = new HashMap<>();
+
+    private boolean bWantTrace = true;
+    private String filePath;
+
+    public enum ReportType {WARNING, CRITICAL, NOT_ANALYZED}
+
+    public ExceptionCollector(String filePath) {
+        this.filePath = filePath;
+    }
+
+    public void appendException(String exception) {
+
+        addException(exception, ReportType.NOT_ANALYZED);
+    }
+
+    public void appendCriticalException(String exception) {
+
+        addException(exception, ReportType.CRITICAL);
+    }
+
+    public void appendWarning(String exception) {
+
+        addException(exception, ReportType.WARNING);
+    }
+
+    private void addException(String exception, ReportType type) {
+
+        Map<String, String> exceptions = getExceptionCollection(type);
+
+        if (!exceptions.containsKey(exception)) {
+            // get stack trace
+            StackTraceElement[] ste = Thread.currentThread().getStackTrace();
+            StringBuilder sb = new StringBuilder();
+            // skip the last 2 (getStackTrace and this)
+            for (int i = 2; i < ste.length; i++) {
+                sb.append(String.format("  %s(%s:%d)%s", ste[i].getClassName(), ste[i].getFileName(),
+                        ste[i].getLineNumber(), i == ste.length - 1 ? " " : "\n"));
+            }
+            exceptions.put(exception, sb.toString());
+        }
+    }
+
+    public List<String> getCriticalsReport() {
+
+        return getReport(ReportType.CRITICAL);
+    }
+
+    public List<String> getNotAnalyzedExceptionsReport() {
+
+        return getReport(ReportType.NOT_ANALYZED);
+    }
+
+    public List<String> getWarningsReport() {
+
+        return getReport(ReportType.WARNING);
+    }
+
+    private List<String> getReport(ReportType type) {
+        Map<String, String> collectedExceptions = getExceptionCollection(type);
+
+        List<String> report = new ArrayList<>();
+        if (collectedExceptions.size() > 0) {
+            for (Map.Entry<String, String> exception : collectedExceptions.entrySet()) {
+                report.add(exception.getKey());
+                if (bWantTrace) {
+                    report.add(exception.getValue());
+                }
+            }
+        }
+
+        return report;
+    }
+
+    private Map<String, String> getExceptionCollection(ReportType type) {
+        switch (type) {
+            case WARNING:
+                return warningExceptions;
+            case CRITICAL:
+                return criticalExceptions;
+            case NOT_ANALYZED:
+                return notAnalyzedExceptions;
+            default:
+                return notAnalyzedExceptions;
+        }
+    }
+
+    public int errorsNotAnalyzedCaught() {
+        return notAnalyzedExceptions.size();
+    }
+
+    public int criticalsCaught() {
+        return criticalExceptions.size();
+    }
+
+    public int warningsCaught() {
+        return warningExceptions.size();
+    }
+
+    public void setWantTrace(boolean b) {
+        bWantTrace = b;
+    }
+
+}
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/common/JToscaException.java b/src/main/java/org/openecomp/sdc/toscaparser/api/common/JToscaException.java
new file mode 100644
index 0000000..6cd5872
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/common/JToscaException.java
@@ -0,0 +1,27 @@
+package org.openecomp.sdc.toscaparser.api.common;
+
+public class JToscaException extends Exception {
+
+	private static final long serialVersionUID = 1L;
+	private String code;
+
+	public JToscaException(String message, String code) {
+		super(message);
+		this.code = code;
+	}
+
+	public String getCode() {
+		return code;
+	}
+
+	public void setCode(String code) {
+		this.code = code;
+	}
+
+	//JT1001 - Meta file missing
+	//JT1002 - Invalid yaml content
+	//JT1003 - Entry-Definition not defined in meta file
+	//JT1004 - Entry-Definition file missing
+	//JT1005 - General Error
+	//JT1006 - General Error/Path not valid
+}
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/common/TOSCAException.java b/src/main/java/org/openecomp/sdc/toscaparser/api/common/TOSCAException.java
new file mode 100644
index 0000000..cfd7560
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/common/TOSCAException.java
@@ -0,0 +1,39 @@
+package org.openecomp.sdc.toscaparser.api.common;
+
+import java.util.IllegalFormatException;
+
+public class TOSCAException extends Exception {
+	private String message = "An unkown exception has occurred";
+	private static boolean FATAL_EXCEPTION_FORMAT_ERRORS = false;
+	private String msgFmt = null;
+
+	public TOSCAException(String...strings) {
+		try {
+			message = String.format(msgFmt,(Object[])strings);
+		}
+		catch (IllegalFormatException e) {
+			// TODO log
+			
+			if(FATAL_EXCEPTION_FORMAT_ERRORS) {
+				throw e;
+			}
+			 
+		}
+		
+	}
+	
+	public String __str__() {
+		return message;
+	}
+	
+	public static void generate_inv_schema_property_error(String name, String attr, String value, String valid_values) {
+		//TODO
+		
+	}
+	
+	public static void setFatalFormatException(boolean flag) {
+		FATAL_EXCEPTION_FORMAT_ERRORS = flag;
+	}
+		
+}
+
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ArtifactTypeDef.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ArtifactTypeDef.java
new file mode 100644
index 0000000..8a13d99
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ArtifactTypeDef.java
@@ -0,0 +1,105 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.LinkedHashMap;
+
+public class ArtifactTypeDef extends StatefulEntityType {
+	
+	private String type;
+	private LinkedHashMap<String,Object> customDef;
+	private LinkedHashMap<String,Object> properties;
+	private LinkedHashMap<String,Object> parentArtifacts;
+ 
+
+
+	public ArtifactTypeDef(String atype,LinkedHashMap<String,Object> _customDef) {
+		super(atype,ARTIFACT_PREFIX,_customDef);
+
+		type = atype;
+		customDef = _customDef;
+		properties = null;
+		if(defs != null) {
+			properties = (LinkedHashMap<String,Object>)defs.get(PROPERTIES);
+		}
+		parentArtifacts = _getParentArtifacts();
+	}
+	
+	private LinkedHashMap<String,Object> _getParentArtifacts() {
+		LinkedHashMap<String,Object> artifacts = new LinkedHashMap<>();
+		String parentArtif = null;
+		if(getParentType() != null) {
+			parentArtif = getParentType().getType();
+		}
+		if(parentArtif != null && !parentArtif.isEmpty()) {
+            while(!parentArtif.equals("tosca.artifacts.Root")) {
+            	Object ob = TOSCA_DEF.get(parentArtif);
+            	artifacts.put(parentArtif,ob);
+                parentArtif = 
+                	(String)((LinkedHashMap<String,Object>)ob).get("derived_from");
+            }
+		}
+		return artifacts;
+	}
+	
+	public ArtifactTypeDef getParentType() {
+        // Return a artifact entity from which this entity is derived
+        if(defs == null) {
+        	return null;
+        }
+        String partifactEntity = derivedFrom(defs);
+        if(partifactEntity != null) {
+            return new ArtifactTypeDef(partifactEntity,customDef);
+        }
+        return null;
+	}
+	
+	public Object getArtifact(String name) {
+        // Return the definition of an artifact field by name
+        if(defs != null) {
+            return defs.get(name);
+        }
+        return null;
+	}
+	
+	public String getType() {
+		return type;
+	}
+	
+}
+
+/*python
+class ArtifactTypeDef(StatefulEntityType):
+    '''TOSCA built-in artifacts type.'''
+
+    def __init__(self, atype, custom_def=None):
+        super(ArtifactTypeDef, self).__init__(atype, self.ARTIFACT_PREFIX,
+                                              custom_def)
+        self.type = atype
+        self.custom_def = custom_def
+        self.properties = None
+        if self.PROPERTIES in self.defs:
+            self.properties = self.defs[self.PROPERTIES]
+        self.parent_artifacts = self._get_parent_artifacts()
+
+    def _get_parent_artifacts(self):
+        artifacts = {}
+        parent_artif = self.parent_type.type if self.parent_type else None
+        if parent_artif:
+            while parent_artif != 'tosca.artifacts.Root':
+                artifacts[parent_artif] = self.TOSCA_DEF[parent_artif]
+                parent_artif = artifacts[parent_artif]['derived_from']
+        return artifacts
+
+    @property
+    def parent_type(self):
+        '''Return a artifact entity from which this entity is derived.'''
+        if not hasattr(self, 'defs'):
+            return None
+        partifact_entity = self.derived_from(self.defs)
+        if partifact_entity:
+            return ArtifactTypeDef(partifact_entity, self.custom_def)
+
+    def get_artifact(self, name):
+        '''Return the definition of an artifact field by name.'''
+        if name in self.defs:
+            return self.defs[name]
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/AttributeDef.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/AttributeDef.java
new file mode 100644
index 0000000..5551908
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/AttributeDef.java
@@ -0,0 +1,40 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.LinkedHashMap;
+
+public class AttributeDef {
+    // TOSCA built-in Attribute type
+	
+	private String name;
+	private Object value;
+	private LinkedHashMap<String,Object> schema;
+
+    public AttributeDef(String adName, Object adValue, LinkedHashMap<String,Object> adSchema) {
+        name = adName;
+        value = adValue;
+        schema = adSchema;
+    }
+    
+    public String getName() {
+    	return name;
+    }
+
+    public Object getValue() {
+    	return value;
+    }
+
+    public LinkedHashMap<String,Object> getSchema() {
+    	return schema;
+    }
+}
+
+/*python
+
+class AttributeDef(object):
+    '''TOSCA built-in Attribute type.'''
+
+    def __init__(self, name, value=None, schema=None):
+        self.name = name
+        self.value = value
+        self.schema = schema
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/CapabilityTypeDef.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/CapabilityTypeDef.java
new file mode 100644
index 0000000..03e2c45
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/CapabilityTypeDef.java
@@ -0,0 +1,222 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.elements.PropertyDef;
+
+public class CapabilityTypeDef extends StatefulEntityType {
+	// TOSCA built-in capabilities type
+
+	private static final String TOSCA_TYPEURI_CAPABILITY_ROOT = "tosca.capabilities.Root";
+
+	private String name;
+	private String nodetype;
+	private LinkedHashMap<String,Object> customDef;
+	private LinkedHashMap<String,Object> properties;
+	private LinkedHashMap<String,Object> parentCapabilities;
+
+	@SuppressWarnings("unchecked")
+	public CapabilityTypeDef(String cname,String ctype,String ntype,LinkedHashMap<String,Object> ccustomDef) {
+		super(ctype,CAPABILITY_PREFIX,ccustomDef);
+		
+		name = cname;
+        nodetype = ntype;
+        properties = null;
+        customDef = ccustomDef;
+        if(defs != null) {
+        	properties = (LinkedHashMap<String,Object>)defs.get(PROPERTIES);
+        }
+        parentCapabilities = _getParentCapabilities(customDef);
+	}
+	
+	@SuppressWarnings("unchecked")
+	public ArrayList<PropertyDef> getPropertiesDefObjects () {
+        // Return a list of property definition objects
+		ArrayList<PropertyDef> propsdefs = new ArrayList<>();
+		LinkedHashMap<String,Object> parentProperties = new LinkedHashMap<>();
+		if(parentCapabilities != null) {
+			for(Map.Entry<String,Object> me: parentCapabilities.entrySet()) {
+				parentProperties.put(me.getKey(),((LinkedHashMap<String,Object>)me.getValue()).get("properties"));
+			}
+		}
+		if(properties != null) {
+			for(Map.Entry<String,Object> me: properties.entrySet()) {
+				propsdefs.add(new PropertyDef(me.getKey(),null,(LinkedHashMap<String,Object>)me.getValue()));
+			}
+		}
+		if(parentProperties != null) {
+			for(Map.Entry<String,Object> me: parentProperties.entrySet()) {
+				LinkedHashMap<String,Object> props = (LinkedHashMap<String,Object>)me.getValue();
+				for(Map.Entry<String,Object> pe: props.entrySet()) {
+					String prop = pe.getKey();
+					LinkedHashMap<String,Object> schema = (LinkedHashMap<String,Object>)pe.getValue();
+                    // add parent property if not overridden by children type
+                    if(properties == null || properties.get(prop) == null) {
+                        propsdefs.add(new PropertyDef(prop, null, schema));
+                    }
+				}
+			}
+		}
+		return propsdefs;
+	}
+
+	public LinkedHashMap<String,PropertyDef> getPropertiesDef() {
+		LinkedHashMap<String,PropertyDef> pds = new LinkedHashMap<>();
+		for(PropertyDef pd: getPropertiesDefObjects()) {
+			pds.put(pd.getName(),pd);
+		}
+		return pds;
+	}
+
+	public PropertyDef getPropertyDefValue(String pdname) {
+        // Return the definition of a given property name
+		LinkedHashMap<String,PropertyDef> propsDef = getPropertiesDef();
+		if(propsDef != null && propsDef.get(pdname) != null) {
+			return (PropertyDef)propsDef.get(pdname).getPDValue();
+		}
+		return null;
+	}
+	
+	@SuppressWarnings("unchecked")
+	private LinkedHashMap<String,Object> _getParentCapabilities(LinkedHashMap<String,Object> customDef) {
+		LinkedHashMap<String,Object> capabilities = new LinkedHashMap<>();
+		CapabilityTypeDef parentCap = getParentType();
+		if(parentCap != null) {
+			String sParentCap = parentCap.getType();
+			while(!sParentCap.equals(TOSCA_TYPEURI_CAPABILITY_ROOT)) {
+				if(TOSCA_DEF.get(sParentCap) != null) {
+					capabilities.put(sParentCap,TOSCA_DEF.get(sParentCap));
+				}
+				else if(customDef != null && customDef.get(sParentCap) != null) {
+					capabilities.put(sParentCap,customDef.get(sParentCap));
+				}
+				sParentCap = (String)((LinkedHashMap<String,Object>)capabilities.get(sParentCap)).get("derived_from");
+			}
+		}
+		return capabilities;
+	}
+
+	public CapabilityTypeDef getParentType() {
+        // Return a capability this capability is derived from
+		if(defs == null) {
+			return null;
+		}
+		String pnode = derivedFrom(defs);
+		if(pnode != null && !pnode.isEmpty()) {
+            return new CapabilityTypeDef(name, pnode, nodetype, customDef);
+		}
+		return null;
+	}
+
+	public boolean inheritsFrom(ArrayList<String> typeNames) {
+        // Check this capability is in type_names
+
+        // Check if this capability or some of its parent types
+        // are in the list of types: type_names
+		if(typeNames.contains(getType())) {
+			return true;
+		}
+		else if(getParentType() != null) {
+			return getParentType().inheritsFrom(typeNames);
+		}
+		return false;
+	}
+
+	// getters/setters
+            		
+	public LinkedHashMap<String,Object> getProperties() {
+		return properties;
+	}
+		
+	public String getName() {
+		return name;
+	}
+}
+
+/*python
+from toscaparser.elements.property_definition import PropertyDef
+from toscaparser.elements.statefulentitytype import StatefulEntityType
+
+
+class CapabilityTypeDef(StatefulEntityType):
+    '''TOSCA built-in capabilities type.'''
+    TOSCA_TYPEURI_CAPABILITY_ROOT = 'tosca.capabilities.Root'
+
+    def __init__(self, name, ctype, ntype, custom_def=None):
+        self.name = name
+        super(CapabilityTypeDef, self).__init__(ctype, self.CAPABILITY_PREFIX,
+                                                custom_def)
+        self.nodetype = ntype
+        self.properties = None
+        self.custom_def = custom_def
+        if self.PROPERTIES in self.defs:
+            self.properties = self.defs[self.PROPERTIES]
+        self.parent_capabilities = self._get_parent_capabilities(custom_def)
+
+    def get_properties_def_objects(self):
+        '''Return a list of property definition objects.'''
+        properties = []
+        parent_properties = {}
+        if self.parent_capabilities:
+            for type, value in self.parent_capabilities.items():
+                parent_properties[type] = value.get('properties')
+        if self.properties:
+            for prop, schema in self.properties.items():
+                properties.append(PropertyDef(prop, None, schema))
+        if parent_properties:
+            for parent, props in parent_properties.items():
+                for prop, schema in props.items():
+                    # add parent property if not overridden by children type
+                    if not self.properties or \
+                            prop not in self.properties.keys():
+                        properties.append(PropertyDef(prop, None, schema))
+        return properties
+
+    def get_properties_def(self):
+        '''Return a dictionary of property definition name-object pairs.'''
+        return {prop.name: prop
+                for prop in self.get_properties_def_objects()}
+
+    def get_property_def_value(self, name):
+        '''Return the definition of a given property name.'''
+        props_def = self.get_properties_def()
+        if props_def and name in props_def:
+            return props_def[name].value
+
+    def _get_parent_capabilities(self, custom_def=None):
+        capabilities = {}
+        parent_cap = self.parent_type
+        if parent_cap:
+            parent_cap = parent_cap.type
+            while parent_cap != self.TOSCA_TYPEURI_CAPABILITY_ROOT:
+                if parent_cap in self.TOSCA_DEF.keys():
+                    capabilities[parent_cap] = self.TOSCA_DEF[parent_cap]
+                elif custom_def and parent_cap in custom_def.keys():
+                    capabilities[parent_cap] = custom_def[parent_cap]
+                parent_cap = capabilities[parent_cap]['derived_from']
+        return capabilities
+
+    @property
+    def parent_type(self):
+        '''Return a capability this capability is derived from.'''
+        if not hasattr(self, 'defs'):
+            return None
+        pnode = self.derived_from(self.defs)
+        if pnode:
+            return CapabilityTypeDef(self.name, pnode,
+                                     self.nodetype, self.custom_def)
+                                     
+    def inherits_from(self, type_names):
+        '''Check this capability is in type_names
+
+           Check if this capability or some of its parent types
+           are in the list of types: type_names
+        '''
+        if self.type in type_names:
+            return True
+        elif self.parent_type:
+            return self.parent_type.inherits_from(type_names)
+        else:
+            return False*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/DataType.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/DataType.java
new file mode 100644
index 0000000..d5d770b
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/DataType.java
@@ -0,0 +1,116 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+public class DataType extends StatefulEntityType {
+	
+	LinkedHashMap<String,Object> customDef; 
+	
+	public DataType(String _dataTypeName,LinkedHashMap<String,Object> _customDef) {
+		super(_dataTypeName,DATATYPE_NETWORK_PREFIX,_customDef);
+		
+		customDef = _customDef;
+	}
+	
+	public DataType getParentType() {
+        // Return a datatype this datatype is derived from
+		if(defs != null) {
+			String ptype = derivedFrom(defs);
+	        if(ptype != null) {
+	            return new DataType(ptype,customDef);
+	        }
+		}
+        return null;
+	}
+
+	public String getValueType() {
+        // Return 'type' section in the datatype schema
+		if(defs != null) {
+			return (String)entityValue(defs,"type");
+		}
+		return null;
+	}
+
+	public ArrayList<PropertyDef> getAllPropertiesObjects() {
+        //Return all properties objects defined in type and parent type
+		ArrayList<PropertyDef> propsDef = getPropertiesDefObjects();
+        DataType ptype = getParentType();
+        while(ptype != null) {
+            propsDef.addAll(ptype.getPropertiesDefObjects());
+            ptype = ptype.getParentType();
+        }
+        return propsDef;
+	}
+	
+	public LinkedHashMap<String,PropertyDef> getAllProperties() {
+        // Return a dictionary of all property definition name-object pairs
+		LinkedHashMap<String,PropertyDef> pno = new LinkedHashMap<>();
+		for(PropertyDef pd: getAllPropertiesObjects()) {
+			pno.put(pd.getName(),pd);
+		}
+        return pno;
+	}
+
+	public Object getAllPropertyValue(String name) {
+        // Return the value of a given property name
+		LinkedHashMap<String,PropertyDef> propsDef = getAllProperties();
+        if(propsDef != null && propsDef.get(name) != null) {
+            return propsDef.get(name).getPDValue();
+        }
+        return null;
+	}
+	
+	public LinkedHashMap<String,Object> getDefs() {
+		return defs;
+	}
+
+}
+
+/*python
+
+from toscaparser.elements.statefulentitytype import StatefulEntityType
+
+
+class DataType(StatefulEntityType):
+    '''TOSCA built-in and user defined complex data type.'''
+
+    def __init__(self, datatypename, custom_def=None):
+        super(DataType, self).__init__(datatypename,
+                                       self.DATATYPE_NETWORK_PREFIX,
+                                       custom_def)
+        self.custom_def = custom_def
+
+    @property
+    def parent_type(self):
+        '''Return a datatype this datatype is derived from.'''
+        ptype = self.derived_from(self.defs)
+        if ptype:
+            return DataType(ptype, self.custom_def)
+        return None
+
+    @property
+    def value_type(self):
+        '''Return 'type' section in the datatype schema.'''
+        return self.entity_value(self.defs, 'type')
+
+    def get_all_properties_objects(self):
+        '''Return all properties objects defined in type and parent type.'''
+        props_def = self.get_properties_def_objects()
+        ptype = self.parent_type
+        while ptype:
+            props_def.extend(ptype.get_properties_def_objects())
+            ptype = ptype.parent_type
+        return props_def
+
+    def get_all_properties(self):
+        '''Return a dictionary of all property definition name-object pairs.'''
+        return {prop.name: prop
+                for prop in self.get_all_properties_objects()}
+
+    def get_all_property_value(self, name):
+        '''Return the value of a given property name.'''
+        props_def = self.get_all_properties()
+        if props_def and name in props_def.key():
+            return props_def[name].value
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/EntityType.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/EntityType.java
new file mode 100644
index 0000000..650166d
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/EntityType.java
@@ -0,0 +1,418 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.extensions.ExtTools;
+import org.openecomp.sdc.toscaparser.api.utils.CopyUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.yaml.snakeyaml.Yaml;
+
+public class EntityType {
+
+	private static Logger log = LoggerFactory.getLogger(EntityType.class.getName());
+
+	private static final String TOSCA_DEFINITION_1_0_YAML = "TOSCA_definition_1_0.yaml";
+	protected static final String DERIVED_FROM = "derived_from";
+	protected static final String PROPERTIES = "properties";
+	protected static final String ATTRIBUTES = "attributes";
+	protected static final String REQUIREMENTS = "requirements";
+	protected static final String INTERFACES = "interfaces";
+	protected static final String CAPABILITIES = "capabilities";
+	protected static final String TYPE = "type";
+	protected static final String ARTIFACTS = "artifacts";
+	
+	@SuppressWarnings("unused")
+	private static final String SECTIONS[] = {
+			DERIVED_FROM, PROPERTIES, ATTRIBUTES, REQUIREMENTS,
+            INTERFACES, CAPABILITIES, TYPE, ARTIFACTS
+	};
+
+	public static final String  TOSCA_DEF_SECTIONS[] = {
+			"node_types", "data_types", "artifact_types",
+	        "group_types", "relationship_types",
+             "capability_types", "interface_types",
+             "policy_types"};
+
+
+    // TOSCA definition file
+	//private final static String path = EntityType.class.getProtectionDomain().getCodeSource().getLocation().getPath();
+	
+	//private final static String path =  EntityType.class.getClassLoader().getResource("TOSCA_definition_1_0.yaml").getFile();
+    //private final static String TOSCA_DEF_FILE = EntityType.class.getClassLoader().getResourceAsStream("TOSCA_definition_1_0.yaml");
+    
+	private static LinkedHashMap<String,Object> TOSCA_DEF_LOAD_AS_IS = loadTdf();
+	
+	//EntityType.class.getClassLoader().getResourceAsStream("TOSCA_definition_1_0.yaml");
+
+	@SuppressWarnings("unchecked")
+	private static LinkedHashMap<String,Object> loadTdf() {
+		String toscaDefLocation = EntityType.class.getClassLoader().getResource(TOSCA_DEFINITION_1_0_YAML).getFile();
+		InputStream input = EntityType.class.getClassLoader().getResourceAsStream(TOSCA_DEFINITION_1_0_YAML);
+		if (input == null){
+			log.error("EntityType - loadTdf - Couldn't load TOSCA_DEF_FILE {}", toscaDefLocation);
+		}
+		Yaml yaml = new Yaml();
+		Object loaded = yaml.load(input);
+	    //@SuppressWarnings("unchecked")
+	    return (LinkedHashMap<String,Object>) loaded;
+	}
+
+    // Map of definition with pre-loaded values of TOSCA_DEF_FILE_SECTIONS
+	public static LinkedHashMap<String,Object> TOSCA_DEF;
+	static {
+    	TOSCA_DEF = new LinkedHashMap<String,Object>();
+        for(String section: TOSCA_DEF_SECTIONS) {
+        	@SuppressWarnings("unchecked")
+    		LinkedHashMap<String,Object> value = (LinkedHashMap<String,Object>)TOSCA_DEF_LOAD_AS_IS.get(section); 
+        	if(value != null) {
+        		for(String key: value.keySet()) {
+        			TOSCA_DEF.put(key, value.get(key));
+        		}
+        	}
+        }
+	}
+
+	public static final String DEPENDSON = "tosca.relationships.DependsOn";
+	public static final String HOSTEDON = "tosca.relationships.HostedOn";
+	public static final String CONNECTSTO = "tosca.relationships.ConnectsTo";
+	public static final String ATTACHESTO = "tosca.relationships.AttachesTo";
+	public static final String LINKSTO = "tosca.relationships.network.LinksTo";
+	public static final String BINDSTO = "tosca.relationships.network.BindsTo";
+
+    public static final String RELATIONSHIP_TYPE[] = { 
+		"tosca.relationships.DependsOn",
+		"tosca.relationships.HostedOn",
+		"tosca.relationships.ConnectsTo",
+		"tosca.relationships.AttachesTo",
+		"tosca.relationships.network.LinksTo",
+		"tosca.relationships.network.BindsTo"};
+
+	public static final String NODE_PREFIX = "tosca.nodes.";
+	public static final String RELATIONSHIP_PREFIX = "tosca.relationships.";
+	public static final String CAPABILITY_PREFIX = "tosca.capabilities.";
+	public static final String INTERFACE_PREFIX = "tosca.interfaces.";
+	public static final String ARTIFACT_PREFIX = "tosca.artifacts.";
+	public static final String POLICY_PREFIX = "tosca.policies.";
+	public static final String GROUP_PREFIX = "tosca.groups.";
+	//currently the data types are defined only for network
+	// but may have changes in the future.
+	public static final String DATATYPE_PREFIX = "tosca.datatypes.";
+	public static final String DATATYPE_NETWORK_PREFIX = DATATYPE_PREFIX + "network.";
+	public static final String TOSCA = "tosca";
+
+	protected String type;
+	protected LinkedHashMap<String,Object> defs = null;
+	public Object getParentType() { return null; }
+	
+    public String derivedFrom(LinkedHashMap<String,Object> defs) {
+        // Return a type this type is derived from
+        return (String)entityValue(defs, "derived_from");
+    }
+
+    public boolean isDerivedFrom(String type_str) {
+        // Check if object inherits from the given type
+        // Returns true if this object is derived from 'type_str'
+        // False otherwise.
+        if(type == null || this.type.isEmpty()) {
+            return false;
+        }
+        else if(type == type_str) {
+            return true;
+        }
+        else if(getParentType() != null) {
+            return ((EntityType)getParentType()).isDerivedFrom(type_str);
+        }
+        else {
+            return false;
+        }
+    }
+
+    public Object entityValue(LinkedHashMap<String,Object> defs, String key) {
+    	if(defs != null) {
+    		return defs.get(key);
+    	}
+    	return null;
+    }
+
+    @SuppressWarnings("unchecked")
+	public Object getValue(String ndtype, LinkedHashMap<String,Object> _defs, boolean parent) {
+        Object value = null;
+        if(_defs == null) {
+            if(defs == null) {
+                return null;
+            }
+            _defs = this.defs;
+        }
+        Object defndt = _defs.get(ndtype); 
+        if(defndt != null) {
+            // copy the value to avoid that next operations add items in the
+            // item definitions
+            //value = copy.copy(defs[ndtype])
+        	value = CopyUtils.copyLhmOrAl(defndt);
+        }
+        
+        if(parent) {
+            EntityType p = this;
+            if(p != null) {
+                while(p != null) {
+                	if(p.defs != null && p.defs.get(ndtype) != null) {
+                        // get the parent value
+                        Object parentValue = p.defs.get(ndtype);
+                        if(value != null) {
+                            if(value instanceof LinkedHashMap) {
+                            	for(Map.Entry<String,Object> me: ((LinkedHashMap<String,Object>)parentValue).entrySet()) {
+                            		String k = me.getKey();
+                            		if(((LinkedHashMap<String,Object>)value).get(k) == null) {
+                            			((LinkedHashMap<String,Object>)value).put(k,me.getValue());
+                            		}
+                            	}
+                            }
+                            if(value instanceof ArrayList) {
+                            	for(Object pValue: (ArrayList<Object>)parentValue) {
+                            		if(!((ArrayList<Object>)value).contains(pValue)) {
+                            			((ArrayList<Object>)value).add(pValue);
+                            		}
+                            	}
+                            }
+                        }
+                        else {
+                        	// value = copy.copy(parent_value)
+                            value = CopyUtils.copyLhmOrAl(parentValue);
+                        }
+                	}
+                    p = (EntityType)p.getParentType();
+                }
+            }
+        }
+              		
+    	return value;
+	}
+
+    @SuppressWarnings("unchecked")
+	public Object getDefinition(String ndtype) {
+        Object value = null;
+        LinkedHashMap<String,Object> _defs;
+        // no point in hasattr, because we have it, and it 
+        // doesn't do anything except emit an exception anyway
+        //if not hasattr(self, 'defs'):
+        //    defs = None
+        //    ExceptionCollector.appendException(
+        //        ValidationError(message="defs is " + str(defs)))
+        //else:
+        //    defs = self.defs       	
+        _defs = this.defs;
+        
+
+        if(_defs != null && _defs.get(ndtype) != null) {
+        	value = _defs.get(ndtype);
+        }
+
+        Object p = getParentType();
+        if(p != null) {
+        	Object inherited = ((EntityType)p).getDefinition(ndtype);
+        	if(inherited != null) {
+                // inherited = dict(inherited) WTF?!?
+        		if(value == null) {
+        			value = inherited;
+        		}
+        		else {
+        			//?????
+                    //inherited.update(value)
+                    //value.update(inherited)
+        			for(Map.Entry<String,Object> me: ((LinkedHashMap<String,Object>)inherited).entrySet()) {
+        				((LinkedHashMap<String,Object>)value).put(me.getKey(),me.getValue());
+        			}
+        		}
+        	}
+        }
+        return value;
+    }
+    
+   public static void updateDefinitions(String version) {
+        ExtTools exttools = new ExtTools();
+        String extensionDefsFile = exttools.getDefsFile(version);
+        
+		InputStream input = null;
+		try {
+			input = new FileInputStream(new File(extensionDefsFile));
+		} 
+		catch (FileNotFoundException e) {
+			log.error("EntityType - updateDefinitions - Failed to open extension defs file ", extensionDefsFile);
+			return;		
+		}
+		Yaml yaml = new Yaml();
+		LinkedHashMap<String,Object> nfvDefFile = (LinkedHashMap<String,Object>)yaml.load(input);
+		LinkedHashMap<String,Object> nfvDef = new LinkedHashMap<>();
+		for(String section: TOSCA_DEF_SECTIONS) {
+			if(nfvDefFile.get(section) != null) {
+				LinkedHashMap<String,Object> value = 
+						(LinkedHashMap<String,Object>)nfvDefFile.get(section);
+				for(String key: value.keySet()) {
+					nfvDef.put(key, value.get(key));
+				}
+			}
+		}
+		TOSCA_DEF.putAll(nfvDef);
+    }
+    
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import ValidationError
+from toscaparser.extensions.exttools import ExtTools
+import org.openecomp.sdc.toscaparser.api.utils.yamlparser
+
+log = logging.getLogger('tosca')
+
+
+class EntityType(object):
+    '''Base class for TOSCA elements.'''
+
+    SECTIONS = (DERIVED_FROM, PROPERTIES, ATTRIBUTES, REQUIREMENTS,
+                INTERFACES, CAPABILITIES, TYPE, ARTIFACTS) = \
+               ('derived_from', 'properties', 'attributes', 'requirements',
+                'interfaces', 'capabilities', 'type', 'artifacts')
+
+    TOSCA_DEF_SECTIONS = ['node_types', 'data_types', 'artifact_types',
+                          'group_types', 'relationship_types',
+                          'capability_types', 'interface_types',
+                          'policy_types']
+
+    '''TOSCA definition file.'''
+    TOSCA_DEF_FILE = os.path.join(
+        os.path.dirname(os.path.abspath(__file__)),
+        "TOSCA_definition_1_0.yaml")
+
+    loader = toscaparser.utils.yamlparser.load_yaml
+
+    TOSCA_DEF_LOAD_AS_IS = loader(TOSCA_DEF_FILE)
+
+    # Map of definition with pre-loaded values of TOSCA_DEF_FILE_SECTIONS
+    TOSCA_DEF = {}
+    for section in TOSCA_DEF_SECTIONS:
+        if section in TOSCA_DEF_LOAD_AS_IS.keys():
+            value = TOSCA_DEF_LOAD_AS_IS[section]
+            for key in value.keys():
+                TOSCA_DEF[key] = value[key]
+
+    RELATIONSHIP_TYPE = (DEPENDSON, HOSTEDON, CONNECTSTO, ATTACHESTO,
+                         LINKSTO, BINDSTO) = \
+                        ('tosca.relationships.DependsOn',
+                         'tosca.relationships.HostedOn',
+                         'tosca.relationships.ConnectsTo',
+                         'tosca.relationships.AttachesTo',
+                         'tosca.relationships.network.LinksTo',
+                         'tosca.relationships.network.BindsTo')
+
+    NODE_PREFIX = 'tosca.nodes.'
+    RELATIONSHIP_PREFIX = 'tosca.relationships.'
+    CAPABILITY_PREFIX = 'tosca.capabilities.'
+    INTERFACE_PREFIX = 'tosca.interfaces.'
+    ARTIFACT_PREFIX = 'tosca.artifacts.'
+    POLICY_PREFIX = 'tosca.policies.'
+    GROUP_PREFIX = 'tosca.groups.'
+    # currently the data types are defined only for network
+    # but may have changes in the future.
+    DATATYPE_PREFIX = 'tosca.datatypes.'
+    DATATYPE_NETWORK_PREFIX = DATATYPE_PREFIX + 'network.'
+    TOSCA = 'tosca'
+
+    def derived_from(self, defs):
+        '''Return a type this type is derived from.'''
+        return self.entity_value(defs, 'derived_from')
+
+    def is_derived_from(self, type_str):
+        '''Check if object inherits from the given type.
+
+        Returns true if this object is derived from 'type_str'.
+        False otherwise.
+        '''
+        if not self.type:
+            return False
+        elif self.type == type_str:
+            return True
+        elif self.parent_type:
+            return self.parent_type.is_derived_from(type_str)
+        else:
+            return False
+
+    def entity_value(self, defs, key):
+        if key in defs:
+            return defs[key]
+
+    def get_value(self, ndtype, defs=None, parent=None):
+        value = None
+        if defs is None:
+            if not hasattr(self, 'defs'):
+                return None
+            defs = self.defs
+        if ndtype in defs:
+            # copy the value to avoid that next operations add items in the
+            # item definitions
+            value = copy.copy(defs[ndtype])
+        if parent:
+            p = self
+            if p:
+                while p:
+                    if ndtype in p.defs:
+                        # get the parent value
+                        parent_value = p.defs[ndtype]
+                        if value:
+                            if isinstance(value, dict):
+                                for k, v in parent_value.items():
+                                    if k not in value.keys():
+                                        value[k] = v
+                            if isinstance(value, list):
+                                for p_value in parent_value:
+                                    if p_value not in value:
+                                        value.append(p_value)
+                        else:
+                            value = copy.copy(parent_value)
+                    p = p.parent_type
+        return value
+
+    def get_definition(self, ndtype):
+        value = None
+        if not hasattr(self, 'defs'):
+            defs = None
+            ExceptionCollector.appendException(
+                ValidationError(message="defs is " + str(defs)))
+        else:
+            defs = self.defs
+        if defs is not None and ndtype in defs:
+            value = defs[ndtype]
+        p = self.parent_type
+        if p:
+            inherited = p.get_definition(ndtype)
+            if inherited:
+                inherited = dict(inherited)
+                if not value:
+                    value = inherited
+                else:
+                    inherited.update(value)
+                    value.update(inherited)
+        return value
+
+
+def update_definitions(version):
+    exttools = ExtTools()
+    extension_defs_file = exttools.get_defs_file(version)
+    loader = toscaparser.utils.yamlparser.load_yaml
+    nfv_def_file = loader(extension_defs_file)
+    nfv_def = {}
+    for section in EntityType.TOSCA_DEF_SECTIONS:
+        if section in nfv_def_file.keys():
+            value = nfv_def_file[section]
+            for key in value.keys():
+                nfv_def[key] = value[key]
+    EntityType.TOSCA_DEF.update(nfv_def)
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/GroupType.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/GroupType.java
new file mode 100644
index 0000000..d226b78
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/GroupType.java
@@ -0,0 +1,215 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class GroupType extends StatefulEntityType {
+
+	private static final String DERIVED_FROM = "derived_from";
+	private static final String VERSION = "version";
+	private static final String METADATA = "metadata";
+	private static final String DESCRIPTION = "description";
+	private static final String PROPERTIES = "properties";
+	private static final String MEMBERS = "members";
+	private static final String INTERFACES = "interfaces";
+
+	private static final String SECTIONS[] = {
+			DERIVED_FROM, VERSION, METADATA, DESCRIPTION, PROPERTIES, MEMBERS, INTERFACES};
+	
+	private String groupType;
+	private LinkedHashMap<String,Object> customDef;
+	private String groupDescription;
+	private String groupVersion;
+	//private LinkedHashMap<String,Object> groupProperties;
+	//private ArrayList<String> groupMembers;
+	private LinkedHashMap<String,Object> metaData;
+
+	@SuppressWarnings("unchecked")
+	public GroupType(String _grouptype,LinkedHashMap<String,Object> _customDef) {
+		super(_grouptype,GROUP_PREFIX,_customDef);
+		
+		groupType = _grouptype;
+		customDef = _customDef;
+		_validateFields();
+		if(defs != null) {
+			groupDescription = (String)defs.get(DESCRIPTION);
+			groupVersion = (String)defs.get(VERSION);
+			//groupProperties = (LinkedHashMap<String,Object>)defs.get(PROPERTIES);
+			//groupMembers = (ArrayList<String>)defs.get(MEMBERS);
+			Object mdo = defs.get(METADATA);
+			if(mdo instanceof LinkedHashMap) {
+				metaData = (LinkedHashMap<String,Object>)mdo;	
+			}
+			else {
+				metaData = null;
+			}
+			
+			if(metaData != null) {
+				_validateMetadata(metaData);
+			}
+		}
+	}
+		
+	public GroupType getParentType() {
+        // Return a group statefulentity of this entity is derived from.
+        if(defs == null) {
+            return null;
+        }
+        String pgroupEntity = derivedFrom(defs);
+        if(pgroupEntity != null) {
+            return new GroupType(pgroupEntity,customDef);
+        }
+        return null;
+	}
+	
+	public String getDescription() {
+		return groupDescription;
+	}
+
+	public String getVersion() {
+		return groupVersion;
+	}
+	
+	@SuppressWarnings("unchecked")
+	public LinkedHashMap<String,Object> getInterfaces() {
+		Object ifo = getValue(INTERFACES,null,false);
+		if(ifo instanceof LinkedHashMap) {
+			return (LinkedHashMap<String, Object>)ifo;
+		}
+		return new LinkedHashMap<String,Object>();
+	}
+	
+	private void _validateFields() {
+		if(defs != null) {
+			for(String name: defs.keySet()) {
+				boolean bFound = false;
+				for(String sect: SECTIONS) {
+					if(name.equals(sect)) {
+						bFound = true;
+						break;
+					}
+				}
+				if(!bFound) {
+                    ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "UnknownFieldError: Group Type \"%s\" contains unknown field \"%s\"",
+                        groupType,name));
+				}
+			}
+		}
+	}
+	
+	@SuppressWarnings("unchecked")
+	private void _validateMetadata(LinkedHashMap<String,Object> metadata) {
+		String mtt = (String) metadata.get("type");
+		if(mtt != null && !mtt.equals("map") && !mtt.equals("tosca:map")) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                "InvalidTypeError: \"%s\" defined in group for metadata is invalid",
+                mtt));
+		}
+		for(String entrySchema: metadata.keySet()) {
+			Object estob = metadata.get(entrySchema);
+			if(estob instanceof LinkedHashMap) {
+				String est = (String)((LinkedHashMap<String,Object>)estob).get("type");
+				if(!est.equals("string")) {
+	                ThreadLocalsHolder.getCollector().appendException(String.format(
+	                    "InvalidTypeError: \"%s\" defined in group for metadata \"%s\" is invalid",
+	                    est,entrySchema));
+				}
+			}
+		}
+	}
+ 
+	public String getType() {
+		return groupType;
+	}
+
+
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidTypeError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.elements.statefulentitytype import StatefulEntityType
+
+
+class GroupType(StatefulEntityType):
+    '''TOSCA built-in group type.'''
+
+    SECTIONS = (DERIVED_FROM, VERSION, METADATA, DESCRIPTION, PROPERTIES,
+                MEMBERS, INTERFACES) = \
+               ("derived_from", "version", "metadata", "description",
+                "properties", "members", "interfaces")
+
+    def __init__(self, grouptype, custom_def=None):
+        super(GroupType, self).__init__(grouptype, self.GROUP_PREFIX,
+                                        custom_def)
+        self.custom_def = custom_def
+        self.grouptype = grouptype
+        self._validate_fields()
+        self.group_description = None
+        if self.DESCRIPTION in self.defs:
+            self.group_description = self.defs[self.DESCRIPTION]
+
+        self.group_version = None
+        if self.VERSION in self.defs:
+            self.group_version = self.defs[self.VERSION]
+
+        self.group_properties = None
+        if self.PROPERTIES in self.defs:
+            self.group_properties = self.defs[self.PROPERTIES]
+
+        self.group_members = None
+        if self.MEMBERS in self.defs:
+            self.group_members = self.defs[self.MEMBERS]
+
+        if self.METADATA in self.defs:
+            self.meta_data = self.defs[self.METADATA]
+            self._validate_metadata(self.meta_data)
+
+    @property
+    def parent_type(self):
+        '''Return a group statefulentity of this entity is derived from.'''
+        if not hasattr(self, 'defs'):
+            return None
+        pgroup_entity = self.derived_from(self.defs)
+        if pgroup_entity:
+            return GroupType(pgroup_entity, self.custom_def)
+
+    @property
+    def description(self):
+        return self.group_description
+
+    @property
+    def version(self):
+        return self.group_version
+
+    @property
+    def interfaces(self):
+        return self.get_value(self.INTERFACES)
+
+    def _validate_fields(self):
+        if self.defs:
+            for name in self.defs.keys():
+                if name not in self.SECTIONS:
+                    ExceptionCollector.appendException(
+                        UnknownFieldError(what='Group Type %s'
+                                          % self.grouptype, field=name))
+
+    def _validate_metadata(self, meta_data):
+        if not meta_data.get('type') in ['map', 'tosca:map']:
+            ExceptionCollector.appendException(
+                InvalidTypeError(what='"%s" defined in group for '
+                                 'metadata' % (meta_data.get('type'))))
+        for entry_schema, entry_schema_type in meta_data.items():
+            if isinstance(entry_schema_type, dict) and not \
+                    entry_schema_type.get('type') == 'string':
+                ExceptionCollector.appendException(
+                    InvalidTypeError(what='"%s" defined in group for '
+                                     'metadata "%s"'
+                                     % (entry_schema_type.get('type'),
+                                        entry_schema)))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/InterfacesDef.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/InterfacesDef.java
new file mode 100644
index 0000000..8a2b4dd
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/InterfacesDef.java
@@ -0,0 +1,228 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.EntityTemplate;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class InterfacesDef extends StatefulEntityType {
+
+	public static final String LIFECYCLE = "tosca.interfaces.node.lifecycle.Standard";
+	public static final String CONFIGURE = "tosca.interfaces.relationship.Configure";
+	public static final String LIFECYCLE_SHORTNAME = "Standard";
+	public static final String CONFIGURE_SHORTNAME = "Configure";
+
+	public static final String SECTIONS[] = {
+			LIFECYCLE, CONFIGURE, LIFECYCLE_SHORTNAME,CONFIGURE_SHORTNAME
+	};
+
+	public static final String IMPLEMENTATION = "implementation";
+	public static final String INPUTS = "inputs";
+	
+	public static final String INTERFACEVALUE[] = {IMPLEMENTATION, INPUTS};
+
+	public static final String INTERFACE_DEF_RESERVED_WORDS[] = {
+			"type", "inputs", "derived_from", "version", "description"};
+	
+	private EntityType ntype;
+	private EntityTemplate nodeTemplate;
+	private String name;
+	private Object value;
+	private String implementation;
+	private LinkedHashMap<String,Object> inputs;
+
+	
+	@SuppressWarnings("unchecked")
+	public InterfacesDef(EntityType inodeType,
+					     String interfaceType,
+					     EntityTemplate inodeTemplate,
+					     String iname,
+					     Object ivalue) {
+		// void
+		super();
+		
+        ntype = inodeType;
+        nodeTemplate = inodeTemplate;
+        type = interfaceType;
+        name = iname;
+        value = ivalue;
+        implementation = null;
+        inputs = null;
+        defs = new LinkedHashMap<String,Object>();
+
+        if(interfaceType.equals(LIFECYCLE_SHORTNAME)) {
+            interfaceType = LIFECYCLE;
+        }
+        if(interfaceType.equals(CONFIGURE_SHORTNAME)) {
+            interfaceType = CONFIGURE;
+        }
+      
+        // only NodeType has getInterfaces "hasattr(ntype,interfaces)"
+        // while RelationshipType does not
+        if(ntype instanceof NodeType) {
+	        if(((NodeType)ntype).getInterfaces() != null &&
+	        		((NodeType)ntype).getInterfaces().values().contains(interfaceType)) {
+	        	LinkedHashMap<String,Object> nii = (LinkedHashMap<String,Object>)
+	        			((NodeType)ntype).getInterfaces().get(interfaceType);
+	        	interfaceType = (String)nii.get("type");
+	        }
+        }
+        if(inodeType != null) {
+        	if(nodeTemplate != null && nodeTemplate.getCustomDef() != null &&
+        			nodeTemplate.getCustomDef().values().contains(interfaceType)) {
+        		defs = (LinkedHashMap<String,Object>)
+        					nodeTemplate.getCustomDef().get(interfaceType);
+        	}
+        	else {
+        		defs = (LinkedHashMap<String,Object>)TOSCA_DEF.get(interfaceType);
+        	}
+        }
+        
+        if(ivalue != null) {
+        	if(ivalue instanceof LinkedHashMap) {
+        		for(Map.Entry<String,Object> me: ((LinkedHashMap<String,Object>)ivalue).entrySet()) {
+        			if(me.getKey().equals("implementation")) {
+        				implementation = (String)me.getValue();
+        			}
+        			else if(me.getKey().equals("inputs")) {
+        				inputs = (LinkedHashMap<String,Object>)me.getValue();
+        			}
+        			else {
+                        ThreadLocalsHolder.getCollector().appendException(String.format(
+                            "UnknownFieldError: \"interfaces\" of template \"%s\" contain unknown field \"%s\"",
+                            nodeTemplate.getName(),me.getKey()));
+        			}
+        		}
+        	}
+    		else {
+    			implementation = (String)ivalue;
+    		}
+        }
+ 	}
+
+	public ArrayList<String> getLifecycleOps() {
+		if(defs != null) {
+			if(type.equals(LIFECYCLE)) {
+				return _ops();
+			}
+		}
+		return null;
+	}
+	
+	public ArrayList<String> getConfigureOps() {
+		if(defs != null) {
+			if(type.equals(CONFIGURE)) {
+				return _ops();
+			}
+		}
+		return null;
+	}
+	
+	private ArrayList<String> _ops() {
+		return new ArrayList<String>(defs.keySet());
+	}
+	
+	// getters/setters
+	
+	public LinkedHashMap<String,Object> getInputs() {
+		return inputs;
+	}
+	
+	public void setInput(String name,Object value) {
+		inputs.put(name, value);
+	}
+}
+
+/*python
+
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.elements.statefulentitytype import StatefulEntityType
+
+SECTIONS = (LIFECYCLE, CONFIGURE, LIFECYCLE_SHORTNAME,
+            CONFIGURE_SHORTNAME) = \
+           ('tosca.interfaces.node.lifecycle.Standard',
+            'tosca.interfaces.relationship.Configure',
+            'Standard', 'Configure')
+
+INTERFACEVALUE = (IMPLEMENTATION, INPUTS) = ('implementation', 'inputs')
+
+INTERFACE_DEF_RESERVED_WORDS = ['type', 'inputs', 'derived_from', 'version',
+                                'description']
+
+
+class InterfacesDef(StatefulEntityType):
+    '''TOSCA built-in interfaces type.'''
+
+    def __init__(self, node_type, interfacetype,
+                 node_template=None, name=None, value=None):
+        self.ntype = node_type
+        self.node_template = node_template
+        self.type = interfacetype
+        self.name = name
+        self.value = value
+        self.implementation = None
+        self.inputs = None
+        self.defs = {}
+        if interfacetype == LIFECYCLE_SHORTNAME:
+            interfacetype = LIFECYCLE
+        if interfacetype == CONFIGURE_SHORTNAME:
+            interfacetype = CONFIGURE
+        if hasattr(self.ntype, 'interfaces') \
+           and self.ntype.interfaces \
+           and interfacetype in self.ntype.interfaces:
+            interfacetype = self.ntype.interfaces[interfacetype]['type']
+        if node_type:
+            if self.node_template and self.node_template.custom_def \
+               and interfacetype in self.node_template.custom_def:
+                self.defs = self.node_template.custom_def[interfacetype]
+            else:
+                self.defs = self.TOSCA_DEF[interfacetype]
+        if value:
+            if isinstance(self.value, dict):
+                for i, j in self.value.items():
+                    if i == IMPLEMENTATION:
+                        self.implementation = j
+                    elif i == INPUTS:
+                        self.inputs = j
+                    else:
+                        what = ('"interfaces" of template "%s"' %
+                                self.node_template.name)
+                        ExceptionCollector.appendException(
+                            UnknownFieldError(what=what, field=i))
+            else:
+                self.implementation = value
+
+    @property
+    def lifecycle_ops(self):
+        if self.defs:
+            if self.type == LIFECYCLE:
+                return self._ops()
+
+    @property
+    def configure_ops(self):
+        if self.defs:
+            if self.type == CONFIGURE:
+                return self._ops()
+
+    def _ops(self):
+        ops = []
+        for name in list(self.defs.keys()):
+            ops.append(name)
+        return ops
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/Metadata.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/Metadata.java
new file mode 100644
index 0000000..4f7bdd0
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/Metadata.java
@@ -0,0 +1,35 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.Map;
+
+public class Metadata {
+	
+	private final Map<String, Object> metadataMap;
+
+	public Metadata(Map<String, Object> metadataMap) {
+        this.metadataMap = metadataMap;
+    }
+
+	public String getValue(String key)  {
+		return !isEmpty() ? String.valueOf(this.metadataMap.get(key)) : null;
+	}
+	
+	public void setValue(String key, Object value)  {
+		if (!isEmpty())  {
+			this.metadataMap.put(key, value);
+		}
+	}
+
+
+	private boolean isEmpty() {
+		return this.metadataMap == null || this.metadataMap.size() == 0;
+	}
+
+	@Override
+	public String toString() {
+		return "Metadata{" +
+				"metadataMap=" + metadataMap +
+				'}';
+	}
+
+}
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/NodeType.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/NodeType.java
new file mode 100644
index 0000000..d5f1a18
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/NodeType.java
@@ -0,0 +1,523 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.InterfacesDef;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class NodeType extends StatefulEntityType {
+	// TOSCA built-in node type
+	
+	private static final String DERIVED_FROM = "derived_from";
+	private static final String METADATA = "metadata";
+	private static final String PROPERTIES = "properties";
+	private static final String VERSION = "version";
+	private static final String DESCRIPTION = "description";
+	private static final String ATTRIBUTES = "attributes";
+	private static final String REQUIREMENTS = "requirements";
+	private static final String CAPABILITIES = "capabilities";
+	private static final String INTERFACES = "interfaces";
+	private static final String ARTIFACTS = "artifacts";
+
+	private static final String SECTIONS[] = {
+			DERIVED_FROM, METADATA, PROPERTIES, VERSION, DESCRIPTION, ATTRIBUTES, REQUIREMENTS, CAPABILITIES, INTERFACES, ARTIFACTS
+	};
+	
+	private String ntype;
+	public LinkedHashMap<String,Object> customDef;
+	
+	public NodeType(String nttype,LinkedHashMap<String,Object> ntcustomDef) {
+		super(nttype,NODE_PREFIX, ntcustomDef);
+        ntype = nttype;
+        customDef = ntcustomDef;
+        _validateKeys();
+	}
+
+	public Object getParentType() {
+        // Return a node this node is derived from
+		if(defs == null) {
+			return null;
+		}
+		String pnode = derivedFrom(defs);
+		if(pnode != null && !pnode.isEmpty()) {
+            return new NodeType(pnode,customDef);
+		}
+		return null;
+	}
+
+	@SuppressWarnings("unchecked")
+	public LinkedHashMap<RelationshipType,NodeType> getRelationship() {
+        // Return a dictionary of relationships to other node types
+
+        // This method returns a dictionary of named relationships that nodes
+        // of the current node type (self) can have to other nodes (of specific
+        // types) in a TOSCA template.
+
+		LinkedHashMap<RelationshipType,NodeType> relationship = new LinkedHashMap<>();
+		ArrayList<LinkedHashMap<String,Object>> requires;
+		Object treq = getAllRequirements();
+		if(treq != null) {
+            // NOTE(sdmonov): Check if requires is a dict.
+            // If it is a dict convert it to a list of dicts.
+            // This is needed because currently the code below supports only
+            // lists as requirements definition. The following check will
+            // make sure if a map (dict) was provided it will be converted to
+            // a list before proceeding to the parsing.
+            if(treq instanceof LinkedHashMap) {
+            	requires = new ArrayList<>();
+            	for(Map.Entry<String,Object> me: ((LinkedHashMap<String,Object>)treq).entrySet()) {
+            		LinkedHashMap<String,Object> tl = new LinkedHashMap<>();
+            		tl.put(me.getKey(),me.getValue());
+            		requires.add(tl);
+            	}
+            }
+            else {
+            	requires = (ArrayList<LinkedHashMap<String,Object>>)treq;
+            }
+            
+            String keyword = null;
+            String nodeType = null;
+            for(LinkedHashMap<String,Object> require: requires) {
+    			String relation = null;
+            	for(Map.Entry<String,Object> re: require.entrySet()) {
+            		String key = re.getKey();
+            		LinkedHashMap<String,Object> req = (LinkedHashMap<String,Object>)re.getValue();
+            		if(req.get("relationship") != null) {
+            			Object trelation = req.get("relationship");
+            			// trelation is a string or a dict with "type" mapped to the string we want
+            			if(trelation instanceof String) {
+            				relation = (String)trelation;
+            			}
+            			else {
+            				if(((LinkedHashMap<String,Object>)trelation).get("type") != null) {
+            					relation = (String)((LinkedHashMap<String,Object>)trelation).get("type");
+            				}
+            			}
+            			nodeType = (String)req.get("node");
+            			//BUG meaningless?? LinkedHashMap<String,Object> value = req;
+            			if(nodeType != null) {
+            				keyword = "node";
+            			}
+            			else {
+                            // If value is a dict and has a type key
+                            // we need to lookup the node type using
+                            // the capability type
+            				String captype = (String)req.get("capability");
+            				String value = _getNodeTypeByCap(captype);
+            				String getRelation = _getRelation(key,value);
+            				if (getRelation != null)  {
+            					relation = getRelation;
+            				}
+            				keyword = key;
+            				nodeType = value;
+            			}
+            		}
+            		
+            	}
+            	RelationshipType rtype = new RelationshipType(relation, keyword, customDef);
+            	NodeType relatednode = new NodeType(nodeType, customDef);
+            	relationship.put(rtype, relatednode);
+            }
+		}
+		return relationship;
+		
+	}
+	
+    @SuppressWarnings("unchecked")
+	private String _getNodeTypeByCap(String cap) {
+        // Find the node type that has the provided capability
+
+        // This method will lookup all node types if they have the
+        // provided capability.
+
+        // Filter the node types
+        ArrayList<String> nodeTypes = new ArrayList<>();
+        for(String nt: TOSCA_DEF.keySet()) {
+        	if(nt.startsWith(NODE_PREFIX) && !nt.equals("tosca.nodes.Root")) {
+        		nodeTypes.add(nt);
+        	}
+        }
+        for(String nt: nodeTypes) {
+			LinkedHashMap<String,Object> nodeDef = (LinkedHashMap<String,Object>)TOSCA_DEF.get(nt);
+            if(nodeDef instanceof LinkedHashMap && nodeDef.get("capabilities") != null) {
+            	LinkedHashMap<String,Object> nodeCaps = (LinkedHashMap<String,Object>)nodeDef.get("capabilities");
+            	if(nodeCaps != null) {
+            		for(Object val: nodeCaps.values()) {
+            			if(val instanceof LinkedHashMap) {
+            				String tp = (String)((LinkedHashMap<String,Object>)val).get("type");
+            				if(tp != null && tp.equals(cap)) {
+            					return nt;
+            				}
+            			}
+            		}
+            	}
+            }
+        }		
+        return null;
+	}
+    
+    @SuppressWarnings("unchecked")
+	private String _getRelation(String key,String ndtype) {
+    	String relation = null;
+    	NodeType ntype = new NodeType(ndtype,null);
+    	LinkedHashMap<String,CapabilityTypeDef> caps = ntype.getCapabilities();
+    	if(caps != null && caps.get(key) != null) {
+    		CapabilityTypeDef c = caps.get(key);
+    		for(int i=0; i< RELATIONSHIP_TYPE.length; i++) {
+    			String r = RELATIONSHIP_TYPE[i];
+    			LinkedHashMap<String,Object> rtypedef = (LinkedHashMap<String,Object>)TOSCA_DEF.get(r);
+    			for(Object o: rtypedef.values()) {
+    				LinkedHashMap<String,Object> properties = (LinkedHashMap<String,Object>)o;
+    				if(properties.get(c.getType()) != null) {
+    					relation = r;
+    					break;
+    				}
+    			}
+    			if(relation != null) {
+    				break;
+    			}
+    			else {
+        			for(Object o: rtypedef.values()) {
+        				LinkedHashMap<String,Object> properties = (LinkedHashMap<String,Object>)o;
+        				if(properties.get(c.getParentType()) != null) {
+        					relation = r;
+        					break;
+        				}
+        			}
+    			}
+    		}
+    	}
+    	return relation;	
+    }
+
+    @SuppressWarnings("unchecked")
+	public ArrayList<CapabilityTypeDef> getCapabilitiesObjects() {
+        // Return a list of capability objects
+		ArrayList<CapabilityTypeDef> typecapabilities = new ArrayList<>();
+		LinkedHashMap<String,Object> caps = (LinkedHashMap<String,Object>)getValue(CAPABILITIES, null, true);
+        if(caps != null) {
+            // 'cname' is symbolic name of the capability
+            // 'cvalue' is a dict { 'type': <capability type name> }
+        	for(Map.Entry<String,Object> me: caps.entrySet()) {
+        		String cname = me.getKey();
+        		LinkedHashMap<String,String> cvalue = (LinkedHashMap<String,String>)me.getValue();
+        		String ctype = cvalue.get("type");
+        		CapabilityTypeDef cap = new CapabilityTypeDef(cname,ctype,type,customDef);
+        		typecapabilities.add(cap);
+        	}
+        }
+        return typecapabilities;
+	}
+ 
+	public LinkedHashMap<String,CapabilityTypeDef> getCapabilities() {
+        // Return a dictionary of capability name-objects pairs
+		LinkedHashMap<String,CapabilityTypeDef> caps = new LinkedHashMap<>();
+		for(CapabilityTypeDef ctd: getCapabilitiesObjects()) {
+			caps.put(ctd.getName(),ctd);
+		}
+		return caps;
+	}
+
+	@SuppressWarnings("unchecked")
+	public ArrayList<Object> getRequirements() {
+		return (ArrayList<Object>)getValue(REQUIREMENTS,null,true);
+	}
+	
+	public ArrayList<Object> getAllRequirements() {
+		return getRequirements();
+	}
+	
+	@SuppressWarnings("unchecked")
+	public LinkedHashMap<String,Object> getInterfaces() {
+		return (LinkedHashMap<String,Object>)getValue(INTERFACES,null,false);
+	}
+	
+
+	@SuppressWarnings("unchecked")
+	public ArrayList<String> getLifecycleInputs()
+	{
+        // Return inputs to life cycle operations if found
+        ArrayList<String> inputs = new ArrayList<>();
+        LinkedHashMap<String,Object> interfaces = getInterfaces();
+        if(interfaces != null) {
+        	for(Map.Entry<String,Object> me: interfaces.entrySet()) {
+        		String iname = me.getKey();
+        		LinkedHashMap<String,Object> ivalue = (LinkedHashMap<String,Object>)me.getValue();
+        		if(iname.equals(InterfacesDef.LIFECYCLE)) {
+        			for(Map.Entry<String,Object> ie: ivalue.entrySet()) {
+        				if(ie.getKey().equals("input")) {
+        					LinkedHashMap<String,Object> y = (LinkedHashMap<String,Object>)ie.getValue();
+        					for(String i: y.keySet()) {
+        						inputs.add(i);
+        					}
+        				}
+        			}
+        		}
+        	}
+        }
+        return inputs;
+	}
+	
+	public ArrayList<String> getLifecycleOperations() {
+		//  Return available life cycle operations if found
+		ArrayList<String> ops = null;
+		LinkedHashMap<String,Object> interfaces = getInterfaces();
+		if(interfaces != null) {
+			InterfacesDef i = new InterfacesDef(this,InterfacesDef.LIFECYCLE,null,null,null);
+			ops = i.getLifecycleOps();
+		}
+		return ops;
+	}
+	
+	public CapabilityTypeDef getCapability(String name) {
+		//BUG?? the python code has to be wrong
+		// it refers to a bad attribute 'value'...
+		LinkedHashMap<String,CapabilityTypeDef> caps = getCapabilities();
+		if(caps != null) {
+			return caps.get(name);
+		}
+		return null;
+		/*
+	    def get_capability(self, name):
+	        caps = self.get_capabilities()
+	        if caps and name in caps.keys():
+	            return caps[name].value
+		*/
+	}
+
+    public String getCapabilityType(String name) {
+		//BUG?? the python code has to be wrong
+		// it refers to a bad attribute 'value'...
+    	CapabilityTypeDef captype = getCapability(name);
+    	if(captype != null) {
+    		return captype.getType();
+    	}
+    	return null;
+	    /*    	
+	    def get_capability_type(self, name):
+	        captype = self.get_capability(name)
+	        if captype and name in captype.keys():
+	            return captype[name].value
+	     */
+    }
+
+    private void _validateKeys() {
+    	if(defs != null) {
+    		for(String key: defs.keySet()) {
+    			boolean bFound = false;
+    			for(int i=0; i< SECTIONS.length; i++) {
+    				if(key.equals(SECTIONS[i])) {
+    					bFound = true;
+    					break;
+    				}
+    			}
+    			if(!bFound) {
+                    ThreadLocalsHolder.getCollector().appendException(String.format(
+                            "UnknownFieldError: Nodetype \"%s\" has unknown field \"%s\"",ntype,key));
+    			}
+    		}
+    	}
+    }
+
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.elements.capabilitytype import CapabilityTypeDef
+import org.openecomp.sdc.toscaparser.api.elements.interfaces as ifaces
+from toscaparser.elements.interfaces import InterfacesDef
+from toscaparser.elements.relationshiptype import RelationshipType
+from toscaparser.elements.statefulentitytype import StatefulEntityType
+
+
+class NodeType(StatefulEntityType):
+    '''TOSCA built-in node type.'''
+    SECTIONS = (DERIVED_FROM, METADATA, PROPERTIES, VERSION, DESCRIPTION, ATTRIBUTES, REQUIREMENTS, CAPABILITIES, INTERFACES, ARTIFACTS) = \
+               ('derived_from', 'metadata', 'properties', 'version',
+                'description', 'attributes', 'requirements', 'capabilities',
+                'interfaces', 'artifacts')
+
+    def __init__(self, ntype, custom_def=None):
+        super(NodeType, self).__init__(ntype, self.NODE_PREFIX, custom_def)
+        self.ntype = ntype
+        self.custom_def = custom_def
+        self._validate_keys()
+
+    @property
+    def parent_type(self):
+        '''Return a node this node is derived from.'''
+        if not hasattr(self, 'defs'):
+            return None
+        pnode = self.derived_from(self.defs)
+        if pnode:
+            return NodeType(pnode, self.custom_def)
+
+    @property
+    def relationship(self):
+        '''Return a dictionary of relationships to other node types.
+
+        This method returns a dictionary of named relationships that nodes
+        of the current node type (self) can have to other nodes (of specific
+        types) in a TOSCA template.
+
+        '''
+        relationship = {}
+        requires = self.get_all_requirements()
+        if requires:
+            # NOTE(sdmonov): Check if requires is a dict.
+            # If it is a dict convert it to a list of dicts.
+            # This is needed because currently the code below supports only
+            # lists as requirements definition. The following check will
+            # make sure if a map (dict) was provided it will be converted to
+            # a list before proceeding to the parsing.
+            if isinstance(requires, dict):
+                requires = [{key: value} for key, value in requires.items()]
+
+            keyword = None
+            node_type = None
+            for require in requires:
+                for key, req in require.items():
+                    if 'relationship' in req:
+                        relation = req.get('relationship')
+                        if 'type' in relation:
+                            relation = relation.get('type')
+                        node_type = req.get('node')
+                        value = req
+                        if node_type:
+                            keyword = 'node'
+                        else:
+                            # If value is a dict and has a type key
+                            # we need to lookup the node type using
+                            # the capability type
+                            value = req
+                            if isinstance(value, dict):
+                                captype = value['capability']
+                                value = (self.
+                                         _get_node_type_by_cap(key, captype))
+                            relation = self._get_relation(key, value)
+                            keyword = key
+                            node_type = value
+                rtype = RelationshipType(relation, keyword, self.custom_def)
+                relatednode = NodeType(node_type, self.custom_def)
+                relationship[rtype] = relatednode
+        return relationship
+
+    def _get_node_type_by_cap(self, key, cap):
+        '''Find the node type that has the provided capability
+
+        This method will lookup all node types if they have the
+        provided capability.
+        '''
+
+        # Filter the node types
+        node_types = [node_type for node_type in self.TOSCA_DEF.keys()
+                      if node_type.startswith(self.NODE_PREFIX) and
+                      node_type != 'tosca.nodes.Root']
+
+        for node_type in node_types:
+            node_def = self.TOSCA_DEF[node_type]
+            if isinstance(node_def, dict) and 'capabilities' in node_def:
+                node_caps = node_def['capabilities']
+                for value in node_caps.values():
+                    if isinstance(value, dict) and \
+                            'type' in value and value['type'] == cap:
+                        return node_type
+
+    def _get_relation(self, key, ndtype):
+        relation = None
+        ntype = NodeType(ndtype)
+        caps = ntype.get_capabilities()
+        if caps and key in caps.keys():
+            c = caps[key]
+            for r in self.RELATIONSHIP_TYPE:
+                rtypedef = ntype.TOSCA_DEF[r]
+                for properties in rtypedef.values():
+                    if c.type in properties:
+                        relation = r
+                        break
+                if relation:
+                    break
+                else:
+                    for properties in rtypedef.values():
+                        if c.parent_type in properties:
+                            relation = r
+                            break
+        return relation
+
+    def get_capabilities_objects(self):
+        '''Return a list of capability objects.'''
+        typecapabilities = []
+        caps = self.get_value(self.CAPABILITIES, None, True)
+        if caps:
+            # 'name' is symbolic name of the capability
+            # 'value' is a dict { 'type': <capability type name> }
+            for name, value in caps.items():
+                ctype = value.get('type')
+                cap = CapabilityTypeDef(name, ctype, self.type,
+                                        self.custom_def)
+                typecapabilities.append(cap)
+        return typecapabilities
+
+    def get_capabilities(self):
+        '''Return a dictionary of capability name-objects pairs.'''
+        return {cap.name: cap
+                for cap in self.get_capabilities_objects()}
+
+    @property
+    def requirements(self):
+        return self.get_value(self.REQUIREMENTS, None, True)
+
+    def get_all_requirements(self):
+        return self.requirements
+
+    @property
+    def interfaces(self):
+        return self.get_value(self.INTERFACES)
+
+    @property
+    def lifecycle_inputs(self):
+        '''Return inputs to life cycle operations if found.'''
+        inputs = []
+        interfaces = self.interfaces
+        if interfaces:
+            for name, value in interfaces.items():
+                if name == ifaces.LIFECYCLE:
+                    for x, y in value.items():
+                        if x == 'inputs':
+                            for i in y.iterkeys():
+                                inputs.append(i)
+        return inputs
+
+    @property
+    def lifecycle_operations(self):
+        '''Return available life cycle operations if found.'''
+        ops = None
+        interfaces = self.interfaces
+        if interfaces:
+            i = InterfacesDef(self.type, ifaces.LIFECYCLE)
+            ops = i.lifecycle_ops
+        return ops
+
+    def get_capability(self, name):
+        caps = self.get_capabilities()
+        if caps and name in caps.keys():
+            return caps[name].value
+
+    def get_capability_type(self, name):
+        captype = self.get_capability(name)
+        if captype and name in captype.keys():
+            return captype[name].value
+
+    def _validate_keys(self):
+        if self.defs:
+            for key in self.defs.keys():
+                if key not in self.SECTIONS:
+                    ExceptionCollector.appendException(
+                        UnknownFieldError(what='Nodetype"%s"' % self.ntype,
+                                          field=key))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/PolicyType.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/PolicyType.java
new file mode 100644
index 0000000..c60bed1
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/PolicyType.java
@@ -0,0 +1,290 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.TOSCAVersionProperty;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class PolicyType extends StatefulEntityType {
+	
+	private static final String DERIVED_FROM = "derived_from";
+	private static final String METADATA = "metadata";
+	private static final String PROPERTIES = "properties";
+	private static final String VERSION = "version";
+	private static final String DESCRIPTION = "description";
+	private static final String TARGETS = "targets";
+	private static final String TRIGGERS = "triggers";
+	private static final String TYPE = "type";
+
+	private static final String SECTIONS[] = {
+			DERIVED_FROM, METADATA, PROPERTIES, VERSION, DESCRIPTION, TARGETS, TRIGGERS, TYPE
+	};
+
+	private LinkedHashMap<String,Object> customDef;
+	private String policyDescription;
+	private Object policyVersion;
+	private LinkedHashMap<String,Object> properties;
+	private LinkedHashMap<String,Object> parentPolicies;
+	private LinkedHashMap<String,Object> metaData;
+	private ArrayList<String> targetsList;
+	
+	
+	public PolicyType(String _type, LinkedHashMap<String,Object> _customDef) {
+		super(_type,POLICY_PREFIX,_customDef);
+		
+		type = _type;
+		customDef = _customDef;
+		_validateKeys();
+		
+        metaData = null;
+        if(defs != null && defs.get(METADATA) != null) {
+            metaData = (LinkedHashMap<String,Object>)defs.get(METADATA);
+            _validateMetadata(metaData);
+        }
+
+        properties = null;
+        if(defs != null && defs.get(PROPERTIES) != null) {
+        	properties = (LinkedHashMap<String,Object>)defs.get(PROPERTIES);
+        }
+        parentPolicies = _getParentPolicies();
+
+        policyVersion = null;
+        if(defs != null && defs.get(VERSION) != null) {
+            policyVersion = (new TOSCAVersionProperty(
+                defs.get(VERSION))).getVersion();
+        }
+
+        policyDescription = null;
+        if(defs != null && defs.get(DESCRIPTION) != null) {
+        	policyDescription = (String)defs.get(DESCRIPTION);
+        }
+            
+        targetsList = null;
+        if(defs != null && defs.get(TARGETS) != null) {
+        	targetsList = (ArrayList<String>)defs.get(TARGETS);
+            _validateTargets(targetsList,customDef);
+        }
+		
+	}
+
+	private LinkedHashMap<String,Object> _getParentPolicies() {
+		LinkedHashMap<String,Object> policies = new LinkedHashMap<>();
+		String parentPolicy;
+		if(getParentType() != null) {
+			parentPolicy = getParentType().getType();
+		}
+		else {
+			parentPolicy = null;
+		}
+		if(parentPolicy != null) {
+			while(parentPolicy != null && !parentPolicy.equals("tosca.policies.Root")) {
+				policies.put(parentPolicy, TOSCA_DEF.get(parentPolicy));
+				parentPolicy = (String)
+					((LinkedHashMap<String,Object>)policies.get(parentPolicy)).get("derived_from);");
+			}
+		}
+		return policies;
+	}
+
+	public String getType() {
+		return type;
+	}
+
+	public PolicyType getParentType() {
+        // Return a policy statefulentity of this node is derived from
+		if(defs == null) {
+			return null;
+		}
+        String ppolicyEntity = derivedFrom(defs);
+        if(ppolicyEntity != null) {
+            return new PolicyType(ppolicyEntity,customDef);
+        }
+        return null;
+	}
+	
+	public Object getPolicy(String name) {
+        // Return the definition of a policy field by name
+        if(defs != null &&  defs.get(name) != null) {
+            return defs.get(name);
+        }
+        return null;
+	}
+
+	public ArrayList<String> getTargets() {
+        // Return targets
+        return targetsList;
+	}
+	
+	public String getDescription() {
+		return policyDescription;
+	}
+
+	public Object getVersion() {
+		return policyVersion;
+	}
+	
+	private void _validateKeys() {
+		for(String key: defs.keySet()) {
+			boolean bFound = false;
+			for(String sect: SECTIONS) {
+				if(key.equals(sect)) {
+					bFound = true;
+					break;
+				}
+			}
+			if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "UnknownFieldError: Policy \"%s\" contains unknown field \"%s\"",
+                    type,key));
+			}
+		}
+	}
+	
+	private void _validateTargets(ArrayList<String> _targetsList,
+								  LinkedHashMap<String,Object> _customDef) {
+		for(String nodetype: _targetsList) {
+			if(_customDef.get(nodetype) == null) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "InvalidTypeError: \"%s\" defined in targets for policy \"%s\"",
+                    nodetype,type));
+				
+			}
+		}
+	}
+ 
+	private void _validateMetadata(LinkedHashMap<String,Object> _metaData) {
+		String mtype = (String)_metaData.get("type");
+		if(mtype != null && !mtype.equals("map") && !mtype.equals("tosca:map")) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                "InvalidTypeError: \"%s\" defined in policy for metadata",
+                mtype));
+		}
+		for(String entrySchema: metaData.keySet()) {
+			Object estob = metaData.get(entrySchema);
+			if(estob instanceof LinkedHashMap) {
+				String est = (String)
+						((LinkedHashMap<String,Object>)estob).get("type");
+				if(!est.equals("string")) {
+	                ThreadLocalsHolder.getCollector().appendException(String.format(
+	                    "InvalidTypeError: \"%s\" defined in policy for metadata \"%s\"",
+	                    est,entrySchema));
+				}
+			}
+		}
+	}
+
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidTypeError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.elements.statefulentitytype import StatefulEntityType
+from toscaparser.utils.validateutils import TOSCAVersionProperty
+
+
+class PolicyType(StatefulEntityType):
+
+    '''TOSCA built-in policies type.'''
+    SECTIONS = (DERIVED_FROM, METADATA, PROPERTIES, VERSION, DESCRIPTION, TARGETS) = \
+               ('derived_from', 'metadata', 'properties', 'version',
+                'description', 'targets')
+
+    def __init__(self, ptype, custom_def=None):
+        super(PolicyType, self).__init__(ptype, self.POLICY_PREFIX,
+                                         custom_def)
+        self.type = ptype
+        self.custom_def = custom_def
+        self._validate_keys()
+
+        self.meta_data = None
+        if self.METADATA in self.defs:
+            self.meta_data = self.defs[self.METADATA]
+            self._validate_metadata(self.meta_data)
+
+        self.properties = None
+        if self.PROPERTIES in self.defs:
+            self.properties = self.defs[self.PROPERTIES]
+        self.parent_policies = self._get_parent_policies()
+
+        self.policy_version = None
+        if self.VERSION in self.defs:
+            self.policy_version = TOSCAVersionProperty(
+                self.defs[self.VERSION]).get_version()
+
+        self.policy_description = self.defs[self.DESCRIPTION] \
+            if self.DESCRIPTION in self.defs else None
+
+        self.targets_list = None
+        if self.TARGETS in self.defs:
+            self.targets_list = self.defs[self.TARGETS]
+            self._validate_targets(self.targets_list, custom_def)
+
+    def _get_parent_policies(self):
+        policies = {}
+        parent_policy = self.parent_type.type if self.parent_type else None
+        if parent_policy:
+            while parent_policy != 'tosca.policies.Root':
+                policies[parent_policy] = self.TOSCA_DEF[parent_policy]
+                parent_policy = policies[parent_policy]['derived_from']
+        return policies
+
+    @property
+    def parent_type(self):
+        '''Return a policy statefulentity of this node is derived from.'''
+        if not hasattr(self, 'defs'):
+            return None
+        ppolicy_entity = self.derived_from(self.defs)
+        if ppolicy_entity:
+            return PolicyType(ppolicy_entity, self.custom_def)
+
+    def get_policy(self, name):
+        '''Return the definition of a policy field by name.'''
+        if name in self.defs:
+            return self.defs[name]
+
+    @property
+    def targets(self):
+        '''Return targets.'''
+        return self.targets_list
+
+    @property
+    def description(self):
+        return self.policy_description
+
+    @property
+    def version(self):
+        return self.policy_version
+
+    def _validate_keys(self):
+        for key in self.defs.keys():
+            if key not in self.SECTIONS:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Policy "%s"' % self.type,
+                                      field=key))
+
+    def _validate_targets(self, targets_list, custom_def):
+        for nodetype in targets_list:
+            if nodetype not in custom_def:
+                ExceptionCollector.appendException(
+                    InvalidTypeError(what='"%s" defined in targets for '
+                                     'policy "%s"' % (nodetype, self.type)))
+
+    def _validate_metadata(self, meta_data):
+        if not meta_data.get('type') in ['map', 'tosca:map']:
+            ExceptionCollector.appendException(
+                InvalidTypeError(what='"%s" defined in policy for '
+                                 'metadata' % (meta_data.get('type'))))
+
+        for entry_schema, entry_schema_type in meta_data.items():
+            if isinstance(entry_schema_type, dict) and not \
+                    entry_schema_type.get('type') == 'string':
+                ExceptionCollector.appendException(
+                    InvalidTypeError(what='"%s" defined in policy for '
+                                     'metadata "%s"'
+                                     % (entry_schema_type.get('type'),
+                                        entry_schema)))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/PortSpec.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/PortSpec.java
new file mode 100644
index 0000000..8d490ee
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/PortSpec.java
@@ -0,0 +1,160 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.DataEntity;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.openecomp.sdc.toscaparser.api.utils.ValidateUtils;
+
+public class PortSpec {
+    // Parent class for tosca.datatypes.network.PortSpec type
+
+    private static final String SHORTNAME = "PortSpec";
+    private static final String TYPE_URI = "tosca.datatypes.network." + SHORTNAME;
+
+    private static final String PROTOCOL = "protocol";
+    private static final String SOURCE = "source";
+    private static final String SOURCE_RANGE = "source_range";
+    private static final String TARGET = "target";
+    private static final String TARGET_RANGE = "target_range";
+    
+    private static final String PROPERTY_NAMES[] = {
+        PROTOCOL, SOURCE, SOURCE_RANGE,
+        TARGET, TARGET_RANGE
+    };
+	
+    // todo(TBD) May want to make this a subclass of DataType
+    // and change init method to set PortSpec's properties
+    public PortSpec() {
+    	
+    }
+
+    // The following additional requirements MUST be tested:
+    // 1) A valid PortSpec MUST have at least one of the following properties:
+    //   target, target_range, source or source_range.
+    // 2) A valid PortSpec MUST have a value for the source property that
+    //    is within the numeric range specified by the property source_range
+    //    when source_range is specified.
+    // 3) A valid PortSpec MUST have a value for the target property that is
+    //    within the numeric range specified by the property target_range
+    //    when target_range is specified.
+	public static void  validateAdditionalReq(Object _properties,
+											  String propName,
+											  LinkedHashMap<String,Object> custom_def) {
+		
+        try {
+        	LinkedHashMap<String,Object> properties = (LinkedHashMap<String,Object>)_properties;
+            Object source = properties.get(PortSpec.SOURCE);
+            Object sourceRange = properties.get(PortSpec.SOURCE_RANGE);
+            Object target = properties.get(PortSpec.TARGET);
+            Object targetRange = properties.get(PortSpec.TARGET_RANGE);
+
+            // verify one of the specified values is set
+            if(source == null && sourceRange == null && 
+                    target == null && targetRange == null) { 
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "InvalidTypeAdditionalRequirementsError: Additional requirements for type \"%s\" not met",
+                    TYPE_URI));
+            }
+            // Validate source value is in specified range
+            if(source != null &&  sourceRange != null) {
+                ValidateUtils.validateValueInRange(source,sourceRange,SOURCE);
+            }
+            else {
+                DataEntity portdef = new DataEntity("PortDef", source, null, SOURCE);
+                portdef.validate();
+            }
+            // Validate target value is in specified range
+            if(target != null &&  targetRange != null) {
+                ValidateUtils.validateValueInRange(target,targetRange,SOURCE);
+            }
+            else {
+                DataEntity portdef = new DataEntity("PortDef", source, null, TARGET);
+                portdef.validate();
+            }
+        }
+        catch(Exception e) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                "ValueError: \"%s\" do not meet requirements for type \"%s\"", 
+                _properties.toString(),SHORTNAME));
+        }
+ 	}
+
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidTypeAdditionalRequirementsError
+from toscaparser.utils.gettextutils import _
+import org.openecomp.sdc.toscaparser.api.utils.validateutils as validateutils
+
+log = logging.getLogger('tosca')
+
+
+class PortSpec(object):
+    '''Parent class for tosca.datatypes.network.PortSpec type.'''
+
+    SHORTNAME = 'PortSpec'
+    TYPE_URI = 'tosca.datatypes.network.' + SHORTNAME
+
+    PROPERTY_NAMES = (
+        PROTOCOL, SOURCE, SOURCE_RANGE,
+        TARGET, TARGET_RANGE
+    ) = (
+        'protocol', 'source', 'source_range',
+        'target', 'target_range'
+    )
+
+    # TODO(TBD) May want to make this a subclass of DataType
+    # and change init method to set PortSpec's properties
+    def __init__(self):
+        pass
+
+    # The following additional requirements MUST be tested:
+    # 1) A valid PortSpec MUST have at least one of the following properties:
+    #   target, target_range, source or source_range.
+    # 2) A valid PortSpec MUST have a value for the source property that
+    #    is within the numeric range specified by the property source_range
+    #    when source_range is specified.
+    # 3) A valid PortSpec MUST have a value for the target property that is
+    #    within the numeric range specified by the property target_range
+    #    when target_range is specified.
+    @staticmethod
+    def validate_additional_req(properties, prop_name, custom_def=None, ):
+        try:
+            source = properties.get(PortSpec.SOURCE)
+            source_range = properties.get(PortSpec.SOURCE_RANGE)
+            target = properties.get(PortSpec.TARGET)
+            target_range = properties.get(PortSpec.TARGET_RANGE)
+
+            # verify one of the specified values is set
+            if source is None and source_range is None and \
+                    target is None and target_range is None:
+                ExceptionCollector.appendException(
+                    InvalidTypeAdditionalRequirementsError(
+                        type=PortSpec.TYPE_URI))
+            # Validate source value is in specified range
+            if source and source_range:
+                validateutils.validate_value_in_range(source, source_range,
+                                                      PortSpec.SOURCE)
+            else:
+                from toscaparser.dataentity import DataEntity
+                portdef = DataEntity('PortDef', source, None, PortSpec.SOURCE)
+                portdef.validate()
+            # Validate target value is in specified range
+            if target and target_range:
+                validateutils.validate_value_in_range(target, target_range,
+                                                      PortSpec.TARGET)
+            else:
+                from toscaparser.dataentity import DataEntity
+                portdef = DataEntity('PortDef', source, None, PortSpec.TARGET)
+                portdef.validate()
+        except Exception:
+            msg = _('"%(value)s" do not meet requirements '
+                    'for type "%(type)s".') \
+                % {'value': properties, 'type': PortSpec.SHORTNAME}
+            ExceptionCollector.appendException(
+                ValueError(msg))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/PropertyDef.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/PropertyDef.java
new file mode 100644
index 0000000..c139eb6
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/PropertyDef.java
@@ -0,0 +1,231 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class PropertyDef {
+	
+	private static final String PROPERTY_KEYNAME_DEFAULT = "default";
+	private static final String PROPERTY_KEYNAME_REQUIRED = "required";
+	private static final String PROPERTY_KEYNAME_STATUS = "status";
+	private static final String VALID_PROPERTY_KEYNAMES[] = {
+			PROPERTY_KEYNAME_DEFAULT,
+            PROPERTY_KEYNAME_REQUIRED,
+            PROPERTY_KEYNAME_STATUS};
+
+    private static final boolean PROPERTY_REQUIRED_DEFAULT = true;
+
+    private static final String VALID_REQUIRED_VALUES[] = {"true", "false"};
+
+    private static final String PROPERTY_STATUS_SUPPORTED = "supported";
+	private static final String PROPERTY_STATUS_EXPERIMENTAL = "experimental";
+	private static final String VALID_STATUS_VALUES[] = {
+			PROPERTY_STATUS_SUPPORTED, PROPERTY_STATUS_EXPERIMENTAL};
+
+	private static final String PROPERTY_STATUS_DEFAULT = PROPERTY_STATUS_SUPPORTED;
+	
+	private String name;
+	private Object value;
+	private LinkedHashMap<String,Object> schema;
+	private String _status;
+	private boolean _required;
+
+	public PropertyDef(String pdName, Object pdValue, 
+						LinkedHashMap<String,Object>  pdSchema) {
+		name = pdName;
+		value = pdValue;
+		schema = pdSchema;
+        _status = PROPERTY_STATUS_DEFAULT;
+        _required = PROPERTY_REQUIRED_DEFAULT;
+
+        if(schema != null) {
+        	// Validate required 'type' property exists
+        	if(schema.get("type") == null) {
+        		//msg = (_('Schema definition of "%(pname)s" must have a "type" '
+	            //         'attribute.') % dict(pname=self.name))
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	            		"InvalidSchemaError: Schema definition of \"%s\" must have a \"type\" attribute",name));
+        	}
+	        _loadRequiredAttrFromSchema();
+	        _loadStatusAttrFromSchema();
+        }
+	}
+
+	public Object getDefault() {
+		if(schema != null) {
+			for(Map.Entry<String,Object> me: schema.entrySet()) {
+				if(me.getKey().equals(PROPERTY_KEYNAME_DEFAULT)) {
+					return me.getValue();
+				}
+			}
+		}
+		return null;
+	}
+
+	public boolean isRequired() {
+		return _required;
+	}
+
+	private void _loadRequiredAttrFromSchema() {
+        // IF 'required' keyname exists verify it's a boolean,
+        // if so override default
+		Object val = schema.get(PROPERTY_KEYNAME_REQUIRED);
+		if(val != null) {
+			if(val instanceof Boolean) {
+				_required = (boolean)val;
+			}
+			else {
+                //valid_values = ', '.join(self.VALID_REQUIRED_VALUES)
+                //attr = self.PROPERTY_KEYNAME_REQUIRED
+                //TOSCAException.generate_inv_schema_property_error(self,
+                //                                                  attr,
+                //                                                  value,
+                //                                                  valid_values)
+				ThreadLocalsHolder.getCollector().appendException(String.format(
+						"Schema definition of \"%s\" has \"required\" attribute with an invalid value",
+						name));
+			}
+		}
+	}
+	
+	public String getStatus() {
+		return _status;
+	}
+
+	private void _loadStatusAttrFromSchema() {
+        // IF 'status' keyname exists verify it's a boolean,
+        // if so override default
+		String sts = (String)schema.get(PROPERTY_KEYNAME_STATUS);
+		if(sts != null) {
+			boolean bFound = false;
+			for(String vsv: VALID_STATUS_VALUES) {
+				if(vsv.equals(sts)) {
+					bFound = true;
+					break;
+				}
+			}
+			if(bFound) {
+				_status = sts;
+			}
+			else {
+                //valid_values = ', '.join(self.VALID_STATUS_VALUES)
+                //attr = self.PROPERTY_KEYNAME_STATUS
+                //TOSCAException.generate_inv_schema_property_error(self,
+                //                                                  attr,
+                //                                                  value,
+                //                                                  valid_values)
+				ThreadLocalsHolder.getCollector().appendWarning(String.format(
+						"Schema definition of \"%s\" has \"status\" attribute with an invalid value",
+						name));
+			}
+		}
+	}
+	
+	public String getName() {
+		return name;
+	}
+	
+	public LinkedHashMap<String,Object> getSchema() {
+		return schema;
+	}
+	
+	public Object getPDValue() {
+		// there's getValue in EntityType...
+		return value;
+	}
+	
+}
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidSchemaError
+from toscaparser.common.exception import TOSCAException
+from toscaparser.utils.gettextutils import _
+
+
+class PropertyDef(object):
+    '''TOSCA built-in Property type.'''
+
+    VALID_PROPERTY_KEYNAMES = (PROPERTY_KEYNAME_DEFAULT,
+                               PROPERTY_KEYNAME_REQUIRED,
+                               PROPERTY_KEYNAME_STATUS) = \
+        ('default', 'required', 'status')
+
+    PROPERTY_REQUIRED_DEFAULT = True
+
+    VALID_REQUIRED_VALUES = ['true', 'false']
+    VALID_STATUS_VALUES = (PROPERTY_STATUS_SUPPORTED,
+                           PROPERTY_STATUS_EXPERIMENTAL) = \
+        ('supported', 'experimental')
+
+    PROPERTY_STATUS_DEFAULT = PROPERTY_STATUS_SUPPORTED
+
+    def __init__(self, name, value=None, schema=None):
+        self.name = name
+        self.value = value
+        self.schema = schema
+        self._status = self.PROPERTY_STATUS_DEFAULT
+        self._required = self.PROPERTY_REQUIRED_DEFAULT
+
+        # Validate required 'type' property exists
+        try:
+            self.schema['type']
+        except KeyError:
+            msg = (_('Schema definition of "%(pname)s" must have a "type" '
+                     'attribute.') % dict(pname=self.name))
+            ExceptionCollector.appendException(
+                InvalidSchemaError(message=msg))
+
+        if self.schema:
+            self._load_required_attr_from_schema()
+            self._load_status_attr_from_schema()
+
+    @property
+    def default(self):
+        if self.schema:
+            for prop_key, prop_value in self.schema.items():
+                if prop_key == self.PROPERTY_KEYNAME_DEFAULT:
+                    return prop_value
+        return None
+
+    @property
+    def required(self):
+        return self._required
+
+    def _load_required_attr_from_schema(self):
+        # IF 'required' keyname exists verify it's a boolean,
+        # if so override default
+        if self.PROPERTY_KEYNAME_REQUIRED in self.schema:
+            value = self.schema[self.PROPERTY_KEYNAME_REQUIRED]
+            if isinstance(value, bool):
+                self._required = value
+            else:
+                valid_values = ', '.join(self.VALID_REQUIRED_VALUES)
+                attr = self.PROPERTY_KEYNAME_REQUIRED
+                TOSCAException.generate_inv_schema_property_error(self,
+                                                                  attr,
+                                                                  value,
+                                                                  valid_values)
+
+    @property
+    def status(self):
+        return self._status
+
+    def _load_status_attr_from_schema(self):
+        # IF 'status' keyname exists verify it's a valid value,
+        # if so override default
+        if self.PROPERTY_KEYNAME_STATUS in self.schema:
+            value = self.schema[self.PROPERTY_KEYNAME_STATUS]
+            if value in self.VALID_STATUS_VALUES:
+                self._status = value
+            else:
+                valid_values = ', '.join(self.VALID_STATUS_VALUES)
+                attr = self.PROPERTY_KEYNAME_STATUS
+                TOSCAException.generate_inv_schema_property_error(self,
+                                                                  attr,
+                                                                  value,
+                                                                  valid_values)
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/RelationshipType.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/RelationshipType.java
new file mode 100644
index 0000000..3903941
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/RelationshipType.java
@@ -0,0 +1,103 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.EntityType;
+import org.openecomp.sdc.toscaparser.api.elements.StatefulEntityType;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class RelationshipType extends StatefulEntityType {
+
+	private static final String DERIVED_FROM = "derived_from";
+	private static final String VALID_TARGET_TYPES = "valid_target_types";
+	private static final String INTERFACES = "interfaces";
+	private static final String ATTRIBUTES = "attributes";
+	private static final String PROPERTIES = "properties";
+	private static final String DESCRIPTION = "description";
+	private static final String VERSION = "version";
+	private static final String CREDENTIAL = "credential";
+	
+	private static final String SECTIONS[] = {
+			DERIVED_FROM, VALID_TARGET_TYPES, INTERFACES, 
+			ATTRIBUTES, PROPERTIES, DESCRIPTION, VERSION, CREDENTIAL};
+	
+	private String capabilityName;
+	private LinkedHashMap<String,Object> customDef;
+
+	public RelationshipType(String _type, String _capabilityName, LinkedHashMap<String,Object> _customDef) {
+		super(_type,RELATIONSHIP_PREFIX,_customDef);
+		capabilityName = _capabilityName;
+		customDef = _customDef;
+	}
+	
+	public RelationshipType getParentType() {
+        // Return a relationship this reletionship is derived from.'''
+        String prel = derivedFrom(defs);
+        if(prel != null) {
+            return new RelationshipType(prel,null,customDef);
+        }
+        return null;
+	}
+	
+	public Object getValidTargetTypes() {
+		return entityValue(defs,"valid_target_types");
+	}
+	
+	private void _validateKeys() {
+        for(String key:  defs.keySet()) {
+        	boolean bFound = false;
+        	for(int i=0; i< SECTIONS.length; i++) {
+        		if(key.equals(SECTIONS[i])) {
+        			bFound = true;
+        			break;
+        		}
+        	}
+        	if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                        "UnknownFieldError: Relationshiptype \"%s\" has unknown field \"%s\"",type,key));
+        	}
+        }
+	}
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.elements.statefulentitytype import StatefulEntityType
+
+
+class RelationshipType(StatefulEntityType):
+    '''TOSCA built-in relationship type.'''
+    SECTIONS = (DERIVED_FROM, VALID_TARGET_TYPES, INTERFACES,
+                ATTRIBUTES, PROPERTIES, DESCRIPTION, VERSION,
+                CREDENTIAL) = ('derived_from', 'valid_target_types',
+                               'interfaces', 'attributes', 'properties',
+                               'description', 'version', 'credential')
+
+    def __init__(self, type, capability_name=None, custom_def=None):
+        super(RelationshipType, self).__init__(type, self.RELATIONSHIP_PREFIX,
+                                               custom_def)
+        self.capability_name = capability_name
+        self.custom_def = custom_def
+        self._validate_keys()
+
+    @property
+    def parent_type(self):
+        '''Return a relationship this reletionship is derived from.'''
+        prel = self.derived_from(self.defs)
+        if prel:
+            return RelationshipType(prel, self.custom_def)
+
+    @property
+    def valid_target_types(self):
+        return self.entity_value(self.defs, 'valid_target_types')
+
+    def _validate_keys(self):
+        for key in self.defs.keys():
+            if key not in self.SECTIONS:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Relationshiptype "%s"' % self.type,
+                                      field=key))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnit.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnit.java
new file mode 100644
index 0000000..de18cd6
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnit.java
@@ -0,0 +1,262 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.HashMap;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.openecomp.sdc.toscaparser.api.utils.ValidateUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public abstract class ScalarUnit {
+
+	private static Logger log = LoggerFactory.getLogger(ScalarUnit.class.getName());
+
+	private static final String SCALAR_UNIT_SIZE = "scalar-unit.size";
+	private static final String SCALAR_UNIT_FREQUENCY = "scalar-unit.frequency";
+	private static final String SCALAR_UNIT_TIME = "scalar-unit.time";
+	
+	public static final String SCALAR_UNIT_TYPES[] = {
+            SCALAR_UNIT_SIZE, SCALAR_UNIT_FREQUENCY, SCALAR_UNIT_TIME
+	};
+
+	private Object value;
+	protected HashMap<String,Object> SCALAR_UNIT_DICT;
+	protected String SCALAR_UNIT_DEFAULT;
+	
+	public ScalarUnit(Object _value) {
+		value = _value;
+		SCALAR_UNIT_DICT = new HashMap<>();
+		SCALAR_UNIT_DEFAULT = "";
+	}
+	
+	
+	private String _checkUnitInScalarStandardUnits(String inputUnit) {
+        // Check whether the input unit is following specified standard
+		
+        // If unit is not following specified standard, convert it to standard
+        // unit after displaying a warning message.
+		
+		if(SCALAR_UNIT_DICT.get(inputUnit) != null) {
+			return inputUnit;
+		}
+		else {
+			for(String key: SCALAR_UNIT_DICT.keySet()) {
+				if(key.toUpperCase().equals(inputUnit.toUpperCase())) {
+					log.debug("ScalarUnit - _checkUnitInScalarStandardUnits - \n" +
+						"The unit {} does not follow scalar unit standards\n" +
+						"using {} instead",
+						inputUnit, key);
+					return key;
+				}
+			}
+            ThreadLocalsHolder.getCollector().appendWarning(String.format(
+            	"'The unit \"%s\" is not valid. Valid units are \n%s",
+                inputUnit,SCALAR_UNIT_DICT.keySet().toString()));
+            return inputUnit;
+		}
+	}
+	
+	public Object validateScalarUnit() {
+		Pattern pattern = Pattern.compile("([0-9.]+)\\s*(\\w+)");
+		Matcher matcher = pattern.matcher(value.toString());
+		if(matcher.find()) {
+			ValidateUtils.strToNum(matcher.group(1));
+			String scalarUnit = _checkUnitInScalarStandardUnits(matcher.group(2));
+			value = matcher.group(1) + " " + scalarUnit;
+		}
+		else {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                "ValueError: \"%s\" is not a valid scalar-unit",value.toString()));
+		}
+		return value;
+	}
+	
+	public double getNumFromScalarUnit(String unit) {
+		if(unit != null) {
+			unit = _checkUnitInScalarStandardUnits(unit);
+		}
+		else {
+			unit = SCALAR_UNIT_DEFAULT;
+		}
+		Pattern pattern = Pattern.compile("([0-9.]+)\\s*(\\w+)");
+		Matcher matcher = pattern.matcher(value.toString());
+		if(matcher.find()) {
+			ValidateUtils.strToNum(matcher.group(1));
+			String scalarUnit = _checkUnitInScalarStandardUnits(matcher.group(2));
+			value = matcher.group(1) + " " + scalarUnit;
+			Object on1 = ValidateUtils.strToNum(matcher.group(1)) != null ? ValidateUtils.strToNum(matcher.group(1)) : 0;
+			Object on2 = SCALAR_UNIT_DICT.get(matcher.group(2)) != null ? SCALAR_UNIT_DICT.get(matcher.group(2)) : 0; 
+			Object on3 = SCALAR_UNIT_DICT.get(unit) != null ? SCALAR_UNIT_DICT.get(unit) : 0;
+			
+			Double n1 = new Double(on1.toString());
+			Double n2 = new Double(on2.toString());
+			Double n3 = new Double(on3.toString());
+			double converted = n1 * n2 / n3; 
+	        if(Math.abs(converted - Math.round(converted)) < 0.0000000000001 ) {
+	            converted = Math.round(converted);
+	        }
+	        return converted;
+		}
+		return 0l; //???
+	}
+	
+	protected static HashMap<String,String> scalarunitMapping = _getScalarunitMappings();
+	
+	private static HashMap<String,String> _getScalarunitMappings() {
+		HashMap<String,String> map = new HashMap<>();
+	    map.put(SCALAR_UNIT_FREQUENCY,"ScalarUnitFrequency");
+	    map.put(SCALAR_UNIT_SIZE, "ScalarUnitSize");
+	    map.put(SCALAR_UNIT_TIME, "ScalarUnit_Time");
+	    return map;
+	}
+
+	public static ScalarUnit getScalarunitClass(String type,Object val) {
+		if(type.equals(SCALAR_UNIT_SIZE)) {
+			return new ScalarUnitSize(val);
+		}
+		else if(type.equals(SCALAR_UNIT_TIME)) {
+			return new ScalarUnitTime(val);
+		}
+		else if(type.equals(SCALAR_UNIT_FREQUENCY)) {
+			return new ScalarUnitFrequency(val);
+		}
+		return null;
+	}
+
+	public static double getScalarunitValue(String type, Object value, String unit) {
+		if(type.equals(SCALAR_UNIT_SIZE)) {
+			return (new ScalarUnitSize(value)).getNumFromScalarUnit(unit);
+		}
+		if(type.equals(SCALAR_UNIT_TIME)) {
+			return (new ScalarUnitTime(value)).getNumFromScalarUnit(unit);
+		}
+		if(type.equals(SCALAR_UNIT_FREQUENCY)) {
+			return (new ScalarUnitFrequency(value)).getNumFromScalarUnit(unit);
+		}
+        ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "TypeError: \"%s\" is not a valid scalar-unit type",type));
+        return 0.0;
+	}
+	
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.utils.gettextutils import _
+from toscaparser.utils import validateutils
+
+log = logging.getLogger('tosca')
+
+
+class ScalarUnit(object):
+    '''Parent class for scalar-unit type.'''
+
+    SCALAR_UNIT_TYPES = (
+        SCALAR_UNIT_SIZE, SCALAR_UNIT_FREQUENCY, SCALAR_UNIT_TIME
+    ) = (
+        'scalar-unit.size', 'scalar-unit.frequency', 'scalar-unit.time'
+    )
+
+    def __init__(self, value):
+        self.value = value
+
+    def _check_unit_in_scalar_standard_units(self, input_unit):
+        """Check whether the input unit is following specified standard
+
+        If unit is not following specified standard, convert it to standard
+        unit after displaying a warning message.
+        """
+        if input_unit in self.SCALAR_UNIT_DICT.keys():
+            return input_unit
+        else:
+            for key in self.SCALAR_UNIT_DICT.keys():
+                if key.upper() == input_unit.upper():
+                    log.warning(_('The unit "%(unit)s" does not follow '
+                                  'scalar unit standards; using "%(key)s" '
+                                  'instead.') % {'unit': input_unit,
+                                                 'key': key})
+                    return key
+            msg = (_('The unit "%(unit)s" is not valid. Valid units are '
+                     '"%(valid_units)s".') %
+                   {'unit': input_unit,
+                    'valid_units': sorted(self.SCALAR_UNIT_DICT.keys())})
+            ExceptionCollector.appendException(ValueError(msg))
+
+    def validate_scalar_unit(self):
+        regex = re.compile('([0-9.]+)\s*(\w+)')
+        try:
+            result = regex.match(str(self.value)).groups()
+            validateutils.str_to_num(result[0])
+            scalar_unit = self._check_unit_in_scalar_standard_units(result[1])
+            self.value = ' '.join([result[0], scalar_unit])
+            return self.value
+
+        except Exception:
+            ExceptionCollector.appendException(
+                ValueError(_('"%s" is not a valid scalar-unit.')
+                           % self.value))
+
+    def get_num_from_scalar_unit(self, unit=None):
+        if unit:
+            unit = self._check_unit_in_scalar_standard_units(unit)
+        else:
+            unit = self.SCALAR_UNIT_DEFAULT
+        self.validate_scalar_unit()
+
+        regex = re.compile('([0-9.]+)\s*(\w+)')
+        result = regex.match(str(self.value)).groups()
+        converted = (float(validateutils.str_to_num(result[0]))
+                     * self.SCALAR_UNIT_DICT[result[1]]
+                     / self.SCALAR_UNIT_DICT[unit])
+        if converted - int(converted) < 0.0000000000001:
+            converted = int(converted)
+        return converted
+
+
+class ScalarUnit_Size(ScalarUnit):
+
+    SCALAR_UNIT_DEFAULT = 'B'
+    SCALAR_UNIT_DICT = {'B': 1, 'kB': 1000, 'KiB': 1024, 'MB': 1000000,
+                        'MiB': 1048576, 'GB': 1000000000,
+                        'GiB': 1073741824, 'TB': 1000000000000,
+                        'TiB': 1099511627776}
+
+
+class ScalarUnit_Time(ScalarUnit):
+
+    SCALAR_UNIT_DEFAULT = 'ms'
+    SCALAR_UNIT_DICT = {'d': 86400, 'h': 3600, 'm': 60, 's': 1,
+                        'ms': 0.001, 'us': 0.000001, 'ns': 0.000000001}
+
+
+class ScalarUnit_Frequency(ScalarUnit):
+
+    SCALAR_UNIT_DEFAULT = 'GHz'
+    SCALAR_UNIT_DICT = {'Hz': 1, 'kHz': 1000,
+                        'MHz': 1000000, 'GHz': 1000000000}
+
+
+scalarunit_mapping = {
+    ScalarUnit.SCALAR_UNIT_FREQUENCY: ScalarUnit_Frequency,
+    ScalarUnit.SCALAR_UNIT_SIZE: ScalarUnit_Size,
+    ScalarUnit.SCALAR_UNIT_TIME: ScalarUnit_Time,
+    }
+
+
+def get_scalarunit_class(type):
+    return scalarunit_mapping.get(type)
+
+
+def get_scalarunit_value(type, value, unit=None):
+    if type in ScalarUnit.SCALAR_UNIT_TYPES:
+        ScalarUnit_Class = get_scalarunit_class(type)
+        return (ScalarUnit_Class(value).
+                get_num_from_scalar_unit(unit))
+    else:
+        ExceptionCollector.appendException(
+            TypeError(_('"%s" is not a valid scalar-unit type.') % type))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnitFrequency.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnitFrequency.java
new file mode 100644
index 0000000..57a111e
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnitFrequency.java
@@ -0,0 +1,14 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+public class ScalarUnitFrequency extends ScalarUnit {
+
+	public ScalarUnitFrequency(Object value) {
+		super(value);
+	    SCALAR_UNIT_DEFAULT = "GHz";
+	    SCALAR_UNIT_DICT.put("Hz",1L);
+	    SCALAR_UNIT_DICT.put("kHz",1000L);
+	    SCALAR_UNIT_DICT.put("MHz",1000000L);
+	    SCALAR_UNIT_DICT.put("GHz",1000000000L);
+	}
+
+}
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnitSize.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnitSize.java
new file mode 100644
index 0000000..72e7c33
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnitSize.java
@@ -0,0 +1,19 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+public class ScalarUnitSize extends ScalarUnit {
+
+	public ScalarUnitSize(Object value) {
+		super(value);
+		
+	    SCALAR_UNIT_DEFAULT = "B";
+	    SCALAR_UNIT_DICT.put("B",1L);
+	    SCALAR_UNIT_DICT.put("kB",1000L);
+	    SCALAR_UNIT_DICT.put("kiB",1024L);
+	    SCALAR_UNIT_DICT.put("MB",1000000L);
+	    SCALAR_UNIT_DICT.put("MiB",1048576L);
+	    SCALAR_UNIT_DICT.put("GB",1000000000L);
+	    SCALAR_UNIT_DICT.put("GiB",1073741824L);
+	    SCALAR_UNIT_DICT.put("TB",1000000000000L);
+	    SCALAR_UNIT_DICT.put("TiB",1099511627776L);
+	}
+}
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnitTime.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnitTime.java
new file mode 100644
index 0000000..5cde10a
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/ScalarUnitTime.java
@@ -0,0 +1,17 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+public class ScalarUnitTime extends ScalarUnit {
+
+	public ScalarUnitTime(Object value) {
+		super(value);
+	    SCALAR_UNIT_DEFAULT = "ms";
+	    SCALAR_UNIT_DICT.put("d",86400L);
+	    SCALAR_UNIT_DICT.put("h",3600L);
+	    SCALAR_UNIT_DICT.put("m",60L);
+	    SCALAR_UNIT_DICT.put("s",1L);
+	    SCALAR_UNIT_DICT.put("ms",0.001);
+	    SCALAR_UNIT_DICT.put("us",0.000001);
+	    SCALAR_UNIT_DICT.put("ns",0.000000001);
+	}
+
+}
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/StatefulEntityType.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/StatefulEntityType.java
new file mode 100644
index 0000000..5ab816f
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/StatefulEntityType.java
@@ -0,0 +1,220 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.UnsupportedType;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.AttributeDef;
+import org.openecomp.sdc.toscaparser.api.elements.EntityType;
+import org.openecomp.sdc.toscaparser.api.elements.PropertyDef;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+
+public class StatefulEntityType extends EntityType {
+    // Class representing TOSCA states
+
+    public static final String interfacesNodeLifecycleOperations[] = {
+    	"create", "configure", "start", "stop", "delete"};
+
+    public static final String interfacesRelationshipConfigureOperations[] = {
+    	"post_configure_source", "post_configure_target", "add_target", "remove_target"};
+
+    public StatefulEntityType() {
+    	// void constructor for subclasses that don't want super
+    }
+    
+	@SuppressWarnings("unchecked")
+	public StatefulEntityType(String entityType, String prefix, LinkedHashMap<String,Object> customDef) {
+
+        String entireEntityType = entityType;
+        if(UnsupportedType.validateType(entireEntityType)) {
+            defs = null;
+        }
+        else {
+            if(entityType.startsWith(TOSCA + ":")) {
+                entityType = entityType.substring(TOSCA.length()+1);
+                entireEntityType = prefix + entityType;
+            }
+            if(!entityType.startsWith(TOSCA)) {
+                entireEntityType = prefix + entityType;
+            }
+            if(TOSCA_DEF.get(entireEntityType) != null) {
+                defs = (LinkedHashMap<String,Object> )TOSCA_DEF.get(entireEntityType);
+                entityType = entireEntityType;
+            }
+            else if(customDef != null && customDef.get(entityType) != null) {
+                defs = (LinkedHashMap<String,Object> )customDef.get(entityType);
+            }
+            else{
+                defs = null;
+				ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "InvalidTypeError: \"%s\" is not a valid type",entityType));
+            }
+        }
+        type = entityType;
+	}
+	
+	@SuppressWarnings("unchecked")
+	public ArrayList<PropertyDef> getPropertiesDefObjects() {
+		// Return a list of property definition objects
+		ArrayList<PropertyDef> properties = new ArrayList<PropertyDef>();
+		LinkedHashMap<String,Object> props = (LinkedHashMap<String,Object>)getDefinition(PROPERTIES);
+		if(props != null) {
+			for(Map.Entry<String,Object> me: props.entrySet()) {
+				String pdname = me.getKey();
+				Object to = me.getValue();
+				if(to == null || !(to instanceof LinkedHashMap)) {
+					String s = to == null ? "null" : to.getClass().getSimpleName();
+					ThreadLocalsHolder.getCollector().appendException(String.format(
+							"Unexpected type error: property \"%s\" has type \"%s\" (expected dict)",pdname,s));
+					continue;
+				}
+				LinkedHashMap<String,Object> pdschema = (LinkedHashMap<String,Object>)to;
+				properties.add(new PropertyDef(pdname,null,pdschema));
+			}
+		}
+		return properties;
+	}
+	
+	public LinkedHashMap<String,PropertyDef> getPropertiesDef() {
+		LinkedHashMap<String,PropertyDef> pds = new LinkedHashMap<String,PropertyDef>();
+		for(PropertyDef pd: getPropertiesDefObjects()) {
+			pds.put(pd.getName(),pd);
+		}
+		return pds;
+	}
+	
+	public PropertyDef getPropertyDefValue(String name) {
+		// Return the property definition associated with a given name
+		PropertyDef pd = null;
+		LinkedHashMap<String,PropertyDef> propsDef = getPropertiesDef();
+		if(propsDef != null) {
+			pd = propsDef.get(name);
+		}
+		return pd;
+	}
+	
+	public ArrayList<AttributeDef> getAttributesDefObjects() {
+		// Return a list of attribute definition objects
+		@SuppressWarnings("unchecked")
+		LinkedHashMap<String,Object> attrs = (LinkedHashMap<String,Object>)getValue(ATTRIBUTES,null,true);
+		ArrayList<AttributeDef> ads = new ArrayList<>();
+		if(attrs != null) {
+			for(Map.Entry<String,Object> me: attrs.entrySet()) {
+				String attr = me.getKey();
+				@SuppressWarnings("unchecked")
+				LinkedHashMap<String,Object> adschema = (LinkedHashMap<String,Object>)me.getValue();
+				ads.add(new AttributeDef(attr,null,adschema));
+			}
+		}
+		return ads;
+	}
+
+	public LinkedHashMap<String,AttributeDef> getAttributesDef() {
+		// Return a dictionary of attribute definition name-object pairs
+		
+		LinkedHashMap<String,AttributeDef> ads = new LinkedHashMap<>();
+		for(AttributeDef ado: getAttributesDefObjects()) {
+			ads.put(((AttributeDef)ado).getName(),ado);
+		}
+		return ads;
+	}
+
+	public AttributeDef getAttributeDefValue(String name) {
+		// Return the attribute definition associated with a given name
+		AttributeDef ad = null;
+		LinkedHashMap<String,AttributeDef> attrsDef = getAttributesDef();
+		if(attrsDef != null) {
+			ad = attrsDef.get(name);
+		}
+		return ad;
+	}
+	
+	public String getType() {
+		return type;
+	}
+ }
+
+/*python
+
+from toscaparser.common.exception import InvalidTypeError
+from toscaparser.elements.attribute_definition import AttributeDef
+from toscaparser.elements.entity_type import EntityType
+from toscaparser.elements.property_definition import PropertyDef
+from toscaparser.unsupportedtype import UnsupportedType
+
+
+class StatefulEntityType(EntityType):
+    '''Class representing TOSCA states.'''
+
+    interfaces_node_lifecycle_operations = ['create',
+                                            'configure', 'start',
+                                            'stop', 'delete']
+
+    interfaces_relationship_configure_operations = ['post_configure_source',
+                                                    'post_configure_target',
+                                                    'add_target',
+                                                    'remove_target']
+
+    def __init__(self, entitytype, prefix, custom_def=None):
+        entire_entitytype = entitytype
+        if UnsupportedType.validate_type(entire_entitytype):
+            self.defs = None
+        else:
+            if entitytype.startswith(self.TOSCA + ":"):
+                entitytype = entitytype[(len(self.TOSCA) + 1):]
+                entire_entitytype = prefix + entitytype
+            if not entitytype.startswith(self.TOSCA):
+                entire_entitytype = prefix + entitytype
+            if entire_entitytype in list(self.TOSCA_DEF.keys()):
+                self.defs = self.TOSCA_DEF[entire_entitytype]
+                entitytype = entire_entitytype
+            elif custom_def and entitytype in list(custom_def.keys()):
+                self.defs = custom_def[entitytype]
+            else:
+                self.defs = None
+                ExceptionCollector.appendException(
+                    InvalidTypeError(what=entitytype))
+        self.type = entitytype
+
+    def get_properties_def_objects(self):
+        '''Return a list of property definition objects.'''
+        properties = []
+        props = self.get_definition(self.PROPERTIES)
+        if props:
+            for prop, schema in props.items():
+                properties.append(PropertyDef(prop, None, schema))
+        return properties
+
+    def get_properties_def(self):
+        '''Return a dictionary of property definition name-object pairs.'''
+        return {prop.name: prop
+                for prop in self.get_properties_def_objects()}
+
+    def get_property_def_value(self, name):
+        '''Return the property definition associated with a given name.'''
+        props_def = self.get_properties_def()
+        if props_def and name in props_def.keys():
+            return props_def[name].value
+
+    def get_attributes_def_objects(self):
+        '''Return a list of attribute definition objects.'''
+        attrs = self.get_value(self.ATTRIBUTES, parent=True)
+        if attrs:
+            return [AttributeDef(attr, None, schema)
+                    for attr, schema in attrs.items()]
+        return []
+
+    def get_attributes_def(self):
+        '''Return a dictionary of attribute definition name-object pairs.'''
+        return {attr.name: attr
+                for attr in self.get_attributes_def_objects()}
+
+    def get_attribute_def_value(self, name):
+        '''Return the attribute definition associated with a given name.'''
+        attrs_def = self.get_attributes_def()
+        if attrs_def and name in attrs_def.keys():
+            return attrs_def[name].value
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/TypeValidation.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/TypeValidation.java
new file mode 100644
index 0000000..2caf5c4
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/TypeValidation.java
@@ -0,0 +1,151 @@
+package org.openecomp.sdc.toscaparser.api.elements;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.extensions.ExtTools;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class TypeValidation {
+
+	private static final String DEFINITION_VERSION = "tosca_definitions_version";
+	private static final String DESCRIPTION = "description";
+	private static final String IMPORTS = "imports";
+	private static final String DSL_DEFINITIONS = "dsl_definitions";
+	private static final String NODE_TYPES = "node_types";
+	private static final String REPOSITORIES = "repositories";
+	private static final String DATA_TYPES = "data_types";
+	private static final String ARTIFACT_TYPES = "artifact_types";
+	private static final String GROUP_TYPES = "group_types";
+	private static final String RELATIONSHIP_TYPES = "relationship_types";
+	private static final String CAPABILITY_TYPES = "capability_types";
+	private static final String INTERFACE_TYPES = "interface_types";
+	private static final String POLICY_TYPES = "policy_types";
+	private static final String TOPOLOGY_TEMPLATE = "topology_template";
+	//Pavel
+	private static final String METADATA = "metadata";
+
+    private String ALLOWED_TYPE_SECTIONS[] = { 
+    		DEFINITION_VERSION, DESCRIPTION, IMPORTS,
+            DSL_DEFINITIONS, NODE_TYPES, REPOSITORIES,
+            DATA_TYPES, ARTIFACT_TYPES, GROUP_TYPES,
+            RELATIONSHIP_TYPES, CAPABILITY_TYPES,
+            INTERFACE_TYPES, POLICY_TYPES,
+            TOPOLOGY_TEMPLATE, METADATA
+    };
+
+    private static ArrayList<String> VALID_TEMPLATE_VERSIONS = _getVTV();
+    
+    private static ArrayList<String> _getVTV() {
+    	ArrayList<String> vtv = new ArrayList<>();
+    	vtv.add("tosca_simple_yaml_1_0");
+    	ExtTools exttools = new ExtTools();
+        vtv.addAll(exttools.getVersions());
+        return vtv;
+    }
+    
+    //private LinkedHashMap<String,Object> customTypes;
+    private Object importDef;
+    //private String version;
+    
+    public TypeValidation(LinkedHashMap<String,Object> _customTypes,
+    					  Object _importDef) {
+        importDef = _importDef;
+        _validateTypeKeys(_customTypes);
+    }
+    
+    private void _validateTypeKeys(LinkedHashMap<String,Object> customTypes) {
+    	
+        String sVersion = (String)customTypes.get(DEFINITION_VERSION);
+        if(sVersion != null) {
+        	_validateTypeVersion(sVersion);
+            //version = sVersion;
+        }
+        for(String name: customTypes.keySet()) {
+        	boolean bFound = false;
+        	for(String ats: ALLOWED_TYPE_SECTIONS) {
+        		if(name.equals(ats)) {
+        			bFound = true;
+        			break;
+        		}
+        	}
+        	if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "UnknownFieldError: Template \"%s\" contains unknown field \"%s\"",
+                    importDef.toString(),name));
+        	}
+        }
+    }
+    
+    private void _validateTypeVersion(String sVersion) {
+    	boolean bFound = false;
+    	String allowed = "";
+    	for(String atv: VALID_TEMPLATE_VERSIONS) {
+    		allowed += "\"" + atv + "\" ";
+    		if(sVersion.equals(atv)) {
+    			bFound = true;
+    			break;
+    		}
+    	}
+    	if(!bFound) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                "InvalidTemplateVersion: version \"%s\" in \"%s\" is not supported\n" +
+                "Allowed versions: [%s]",
+                sVersion,importDef.toString(),allowed));
+    	}    	
+    }
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidTemplateVersion
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.extensions.exttools import ExtTools
+
+
+class TypeValidation(object):
+
+    ALLOWED_TYPE_SECTIONS = (DEFINITION_VERSION, DESCRIPTION, IMPORTS,
+                             DSL_DEFINITIONS, NODE_TYPES, REPOSITORIES,
+                             DATA_TYPES, ARTIFACT_TYPES, GROUP_TYPES,
+                             RELATIONSHIP_TYPES, CAPABILITY_TYPES,
+                             INTERFACE_TYPES, POLICY_TYPES,
+                             TOPOLOGY_TEMPLATE) = \
+        ('tosca_definitions_version', 'description', 'imports',
+         'dsl_definitions', 'node_types', 'repositories',
+         'data_types', 'artifact_types', 'group_types',
+         'relationship_types', 'capability_types',
+         'interface_types', 'policy_types', 'topology_template')
+    VALID_TEMPLATE_VERSIONS = ['tosca_simple_yaml_1_0']
+    exttools = ExtTools()
+    VALID_TEMPLATE_VERSIONS.extend(exttools.get_versions())
+
+    def __init__(self, custom_types, import_def):
+        self.import_def = import_def
+        self._validate_type_keys(custom_types)
+
+    def _validate_type_keys(self, custom_type):
+        version = custom_type[self.DEFINITION_VERSION] \
+            if self.DEFINITION_VERSION in custom_type \
+            else None
+        if version:
+            self._validate_type_version(version)
+            self.version = version
+
+        for name in custom_type:
+            if name not in self.ALLOWED_TYPE_SECTIONS:
+                ExceptionCollector.appendException(
+#                    UnknownFieldError(what='Template ' + (self.import_def),
+                    UnknownFieldError(what= (self.import_def),
+                                      field=name))
+
+    def _validate_type_version(self, version):
+        if version not in self.VALID_TEMPLATE_VERSIONS:
+            ExceptionCollector.appendException(
+                InvalidTemplateVersion(
+#                    what=version + ' in ' + self.import_def,
+                    what=self.import_def,
+                    valid_versions=', '. join(self.VALID_TEMPLATE_VERSIONS)))    
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Constraint.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Constraint.java
new file mode 100644
index 0000000..3c60a66
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Constraint.java
@@ -0,0 +1,237 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.ScalarUnit;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public abstract class Constraint {
+	
+	// Parent class for constraints for a Property or Input
+	
+	protected static final String EQUAL = "equal";
+	protected static final String GREATER_THAN = "greater_than";
+	protected static final String GREATER_OR_EQUAL = "greater_or_equal";
+	protected static final String LESS_THAN = "less_than";
+	protected static final String LESS_OR_EQUAL = "less_or_equal";
+	protected static final String IN_RANGE = "in_range";
+	protected static final String VALID_VALUES = "valid_values";
+	protected static final String LENGTH = "length";
+	protected static final String MIN_LENGTH = "min_length";
+	protected static final String MAX_LENGTH = "max_length";
+	protected static final String PATTERN = "pattern";
+
+	protected static final String CONSTRAINTS[] = {
+			EQUAL, GREATER_THAN,GREATER_OR_EQUAL, LESS_THAN, LESS_OR_EQUAL, 
+			IN_RANGE, VALID_VALUES, LENGTH, MIN_LENGTH, MAX_LENGTH, PATTERN};
+
+	@SuppressWarnings("unchecked")
+	public static Constraint factory(String constraintClass,String propname,String proptype,Object constraint) {
+
+		// a factory for the different Constraint classes
+		// replaces Python's __new__() usage
+
+        if(!(constraint instanceof LinkedHashMap) || 
+        		((LinkedHashMap<String,Object>)constraint).size() != 1) {
+                 ThreadLocalsHolder.getCollector().appendException(
+                     "InvalidSchemaError: Invalid constraint schema " + constraint.toString());
+        }
+        
+        if(constraintClass.equals(EQUAL)) {
+        	return new Equal(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(GREATER_THAN)) {
+        	return new GreaterThan(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(GREATER_OR_EQUAL)) {
+        	return new GreaterOrEqual(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(LESS_THAN)) {
+        	return new LessThan(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(LESS_OR_EQUAL)) {
+        	return new LessOrEqual(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(IN_RANGE)) {
+        	return new InRange(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(VALID_VALUES)) {
+        	return new ValidValues(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(LENGTH)) {
+        	return new Length(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(MIN_LENGTH)) {
+        	return new MinLength(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(MAX_LENGTH)) {
+        	return new MaxLength(propname,proptype,constraint);
+        }
+        else if(constraintClass.equals(PATTERN)) {
+        	return new Pattern(propname,proptype,constraint);
+        }
+        else {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+            		"InvalidSchemaError: Invalid property \"%s\"",constraintClass));
+            return null;
+        }
+	}
+	
+	protected String constraintKey = "TBD";
+	protected ArrayList<String> validTypes = new ArrayList<>();
+	protected ArrayList<String> validPropTypes = new ArrayList<>();
+	
+	protected String propertyName;
+	protected String propertyType;
+	protected Object constraintValue;
+	protected Object constraintValueMsg;
+	protected Object valueMsg;
+	
+	@SuppressWarnings("unchecked")
+	public Constraint(String propname,String proptype,Object constraint) {
+		
+		_setValues();
+		
+        propertyName = propname;
+        propertyType = proptype;
+        constraintValue = ((LinkedHashMap<String,Object>)constraint).get(constraintKey);
+        constraintValueMsg = constraintValue;
+        boolean bFound = false;
+        for(String s: ScalarUnit.SCALAR_UNIT_TYPES) {
+        	if(s.equals(propertyType)) {
+        		bFound = true;
+        		break;
+        	}
+        }
+        if(bFound) {
+            constraintValue = _getScalarUnitConstraintValue();
+        }
+        // check if constraint is valid for property type
+        bFound = false;
+        for(String s: validPropTypes) {
+        	if(s.equals(propertyType)) {
+        		bFound = true;
+        		break;
+        	}
+        }
+        if(!bFound) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+            	"InvalidSchemaError: Property \"%s\" is not valid for data type \"%s\"",
+            	constraintKey,propertyType));
+        }
+	}
+
+	@SuppressWarnings("unchecked")
+	private Object _getScalarUnitConstraintValue() {
+		// code differs from Python because of class creation
+		if(constraintValue instanceof ArrayList) {
+			ArrayList<Object> ret = new ArrayList<>();
+			for(Object v: (ArrayList<Object>)constraintValue) {
+				ScalarUnit su = ScalarUnit.getScalarunitClass(propertyType,v);
+				ret.add(su.getNumFromScalarUnit(null));
+			}
+			return ret;
+		}
+		else {
+			ScalarUnit su = ScalarUnit.getScalarunitClass(propertyType,constraintValue);
+			return su.getNumFromScalarUnit(null);
+		}
+	}
+
+	public void validate(Object value) {
+		valueMsg = value;
+        boolean bFound = false;
+        for(String s: ScalarUnit.SCALAR_UNIT_TYPES) {
+        	if(s.equals(propertyType)) {
+        		bFound = true;
+        		break;
+        	}
+        }
+        if(bFound) {
+        	value = ScalarUnit.getScalarunitValue(propertyType,value,null);
+        }
+        if(!_isValid(value)) {
+            ThreadLocalsHolder.getCollector().appendWarning("ValidationError: " + _errMsg(value));
+        }
+	}
+
+	protected abstract boolean _isValid(Object value);
+	
+	protected abstract void _setValues();
+
+	protected abstract String _errMsg(Object value);
+	
+}
+
+/*python
+
+class Constraint(object):
+    '''Parent class for constraints for a Property or Input.'''
+
+    CONSTRAINTS = (EQUAL, GREATER_THAN,
+                   GREATER_OR_EQUAL, LESS_THAN, LESS_OR_EQUAL, IN_RANGE,
+                   VALID_VALUES, LENGTH, MIN_LENGTH, MAX_LENGTH, PATTERN) = \
+                  ('equal', 'greater_than', 'greater_or_equal', 'less_than',
+                   'less_or_equal', 'in_range', 'valid_values', 'length',
+                   'min_length', 'max_length', 'pattern')
+
+    def __new__(cls, property_name, property_type, constraint):
+        if cls is not Constraint:
+            return super(Constraint, cls).__new__(cls)
+
+        if(not isinstance(constraint, collections.Mapping) or
+           len(constraint) != 1):
+            ExceptionCollector.appendException(
+                InvalidSchemaError(message=_('Invalid constraint schema.')))
+
+        for type in constraint.keys():
+            ConstraintClass = get_constraint_class(type)
+            if not ConstraintClass:
+                msg = _('Invalid property "%s".') % type
+                ExceptionCollector.appendException(
+                    InvalidSchemaError(message=msg))
+
+        return ConstraintClass(property_name, property_type, constraint)
+
+    def __init__(self, property_name, property_type, constraint):
+        self.property_name = property_name
+        self.property_type = property_type
+        self.constraint_value = constraint[self.constraint_key]
+        self.constraint_value_msg = self.constraint_value
+        if self.property_type in scalarunit.ScalarUnit.SCALAR_UNIT_TYPES:
+            self.constraint_value = self._get_scalarunit_constraint_value()
+        # check if constraint is valid for property type
+        if property_type not in self.valid_prop_types:
+            msg = _('Property "%(ctype)s" is not valid for data type '
+                    '"%(dtype)s".') % dict(
+                        ctype=self.constraint_key,
+                        dtype=property_type)
+            ExceptionCollector.appendException(InvalidSchemaError(message=msg))
+
+    def _get_scalarunit_constraint_value(self):
+        if self.property_type in scalarunit.ScalarUnit.SCALAR_UNIT_TYPES:
+            ScalarUnit_Class = (scalarunit.
+                                get_scalarunit_class(self.property_type))
+        if isinstance(self.constraint_value, list):
+            return [ScalarUnit_Class(v).get_num_from_scalar_unit()
+                    for v in self.constraint_value]
+        else:
+            return (ScalarUnit_Class(self.constraint_value).
+                    get_num_from_scalar_unit())
+
+    def _err_msg(self, value):
+        return _('Property "%s" could not be validated.') % self.property_name
+
+    def validate(self, value):
+        self.value_msg = value
+        if self.property_type in scalarunit.ScalarUnit.SCALAR_UNIT_TYPES:
+            value = scalarunit.get_scalarunit_value(self.property_type, value)
+        if not self._is_valid(value):
+            err_msg = self._err_msg(value)
+            ExceptionCollector.appendException(
+                ValidationError(message=err_msg))
+
+
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Equal.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Equal.java
new file mode 100644
index 0000000..e16cac3
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Equal.java
@@ -0,0 +1,61 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+public class Equal extends Constraint {
+
+	protected void _setValues() {
+
+		constraintKey = EQUAL;
+		
+		for(String s: Schema.PROPERTY_TYPES) {
+			validPropTypes.add(s);
+		}
+		
+	}
+	
+	public Equal(String name,String type,Object c) {
+		super(name,type,c);
+		
+	}
+	
+	protected boolean _isValid(Object val) {
+		// equality of objects is tricky so we're comparing 
+		// the toString() representation
+		if(val.toString().equals(constraintValue.toString())) {
+			return true;
+		}
+		return false;
+	}
+	
+	protected String _errMsg(Object value) {
+	    return String.format("The value \"%s\" of property \"%s\" is not equal to \"%s\"",
+	    		valueMsg,propertyName,constraintValueMsg);
+	}
+
+}
+
+/*python
+
+class Equal(Constraint):
+"""Constraint class for "equal"
+
+Constrains a property or parameter to a value equal to ('=')
+the value declared.
+"""
+
+constraint_key = Constraint.EQUAL
+
+valid_prop_types = Schema.PROPERTY_TYPES
+
+def _is_valid(self, value):
+    if value == self.constraint_value:
+        return True
+
+    return False
+
+def _err_msg(self, value):
+    return (_('The value "%(pvalue)s" of property "%(pname)s" is not '
+              'equal to "%(cvalue)s".') %
+            dict(pname=self.property_name,
+                 pvalue=self.value_msg,
+                 cvalue=self.constraint_value_msg))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/GreaterOrEqual.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/GreaterOrEqual.java
new file mode 100644
index 0000000..021bed3
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/GreaterOrEqual.java
@@ -0,0 +1,113 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.Date;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.functions.Function;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class GreaterOrEqual extends Constraint {
+	// Constraint class for "greater_or_equal"
+
+	// Constrains a property or parameter to a value greater than or equal
+	// to ('>=') the value declared.
+
+	protected void _setValues() {
+
+		constraintKey = GREATER_OR_EQUAL;
+
+		validTypes.add("Integer");
+		validTypes.add("Double");
+		validTypes.add("Float");
+		// timestamps are loaded as Date objects
+		validTypes.add("Date");
+		//validTypes.add("datetime.date");
+		//validTypes.add("datetime.time");
+		//validTypes.add("datetime.datetime");
+		
+		validPropTypes.add(Schema.INTEGER);
+		validPropTypes.add(Schema.FLOAT);
+		validPropTypes.add(Schema.TIMESTAMP);
+		validPropTypes.add(Schema.SCALAR_UNIT_SIZE);
+		validPropTypes.add(Schema.SCALAR_UNIT_FREQUENCY);
+		validPropTypes.add(Schema.SCALAR_UNIT_TIME);
+		
+	}
+	
+	public GreaterOrEqual(String name,String type,Object c) {
+		super(name,type,c);
+		
+		if(!validTypes.contains(constraintValue.getClass().getSimpleName())) {
+	        ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: The property \"greater_or_equal\" expects comparable values");
+		}
+	}
+	
+	
+
+	@Override
+	protected boolean _isValid(Object value) {
+	    if(Function.isFunction(value)) {
+	        return true;
+		}
+
+	    // timestamps
+	    if(value instanceof Date) {
+	    	if(constraintValue instanceof Date) {
+	    		return !((Date)value).before((Date)constraintValue);
+	    	}
+	    	return false;
+	    }
+	    // all others
+		Double n1 = new Double(value.toString());
+		Double n2 = new Double(constraintValue.toString());
+		return n1 >= n2;
+	}
+
+	protected String _errMsg(Object value) {
+	    return String.format("The value \"%s\" of property \"%s\" must be greater or equal to \"%s\"",
+	    		valueMsg,propertyName,constraintValueMsg);
+	}
+}
+
+/*python
+
+class GreaterOrEqual(Constraint):
+"""Constraint class for "greater_or_equal"
+
+Constrains a property or parameter to a value greater than or equal
+to ('>=') the value declared.
+"""
+
+constraint_key = Constraint.GREATER_OR_EQUAL
+
+valid_types = (int, float, datetime.date,
+               datetime.time, datetime.datetime)
+
+valid_prop_types = (Schema.INTEGER, Schema.FLOAT, Schema.TIMESTAMP,
+                    Schema.SCALAR_UNIT_SIZE, Schema.SCALAR_UNIT_FREQUENCY,
+                    Schema.SCALAR_UNIT_TIME)
+
+def __init__(self, property_name, property_type, constraint):
+    super(GreaterOrEqual, self).__init__(property_name, property_type,
+                                         constraint)
+    if not isinstance(self.constraint_value, self.valid_types):
+        ThreadLocalsHolder.getCollector().appendException(
+            InvalidSchemaError(message=_('The property '
+                                         '"greater_or_equal" expects '
+                                         'comparable values.')))
+
+def _is_valid(self, value):
+    if toscaparser.functions.is_function(value) or \
+       value >= self.constraint_value:
+        return True
+    return False
+
+def _err_msg(self, value):
+    return (_('The value "%(pvalue)s" of property "%(pname)s" must be '
+              'greater than or equal to "%(cvalue)s".') %
+            dict(pname=self.property_name,
+                 pvalue=self.value_msg,
+                 cvalue=self.constraint_value_msg))
+
+
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/GreaterThan.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/GreaterThan.java
new file mode 100644
index 0000000..d23d7ce
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/GreaterThan.java
@@ -0,0 +1,102 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.Date;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class GreaterThan extends Constraint {
+
+	@Override
+	protected void _setValues() {
+
+		constraintKey = GREATER_THAN;
+
+		validTypes.add("Integer");
+		validTypes.add("Double");
+		validTypes.add("Float");
+		// timestamps are loaded as Date objects
+		validTypes.add("Date");
+		//validTypes.add("datetime.date");
+		//validTypes.add("datetime.time");
+		//validTypes.add("datetime.datetime");
+		
+		
+		validPropTypes.add(Schema.INTEGER);
+		validPropTypes.add(Schema.FLOAT);
+		validPropTypes.add(Schema.TIMESTAMP);
+		validPropTypes.add(Schema.SCALAR_UNIT_SIZE);
+		validPropTypes.add(Schema.SCALAR_UNIT_FREQUENCY);
+		validPropTypes.add(Schema.SCALAR_UNIT_TIME);
+		
+	}
+	
+	public GreaterThan(String name,String type,Object c) {
+		super(name,type,c);
+		
+		if(!validTypes.contains(constraintValue.getClass().getSimpleName())) {
+	        ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: The property \"greater_than\" expects comparable values");
+		}
+	}
+	
+	@Override
+	protected boolean _isValid(Object value) {
+
+		// timestamps
+	    if(value instanceof Date) {
+	    	if(constraintValue instanceof Date) {
+	    		return ((Date)value).after((Date)constraintValue);
+	    	}
+	    	return false;
+	    }
+
+	    Double n1 = new Double(value.toString());
+		Double n2 = new Double(constraintValue.toString());
+		return n1 > n2;
+	}
+
+	protected String _errMsg(Object value) {
+	    return String.format("The value \"%s\" of property \"%s\" must be greater than \"%s\"",
+	    		valueMsg,propertyName,constraintValueMsg);
+	}
+
+}
+
+/*
+class GreaterThan(Constraint):
+    """Constraint class for "greater_than"
+
+    Constrains a property or parameter to a value greater than ('>')
+    the value declared.
+    """
+
+    constraint_key = Constraint.GREATER_THAN
+
+    valid_types = (int, float, datetime.date,
+                   datetime.time, datetime.datetime)
+
+    valid_prop_types = (Schema.INTEGER, Schema.FLOAT, Schema.TIMESTAMP,
+                        Schema.SCALAR_UNIT_SIZE, Schema.SCALAR_UNIT_FREQUENCY,
+                        Schema.SCALAR_UNIT_TIME)
+
+    def __init__(self, property_name, property_type, constraint):
+        super(GreaterThan, self).__init__(property_name, property_type,
+                                          constraint)
+        if not isinstance(constraint[self.GREATER_THAN], self.valid_types):
+            ExceptionCollector.appendException(
+                InvalidSchemaError(message=_('The property "greater_than" '
+                                             'expects comparable values.')))
+
+    def _is_valid(self, value):
+        if value > self.constraint_value:
+            return True
+
+        return False
+
+    def _err_msg(self, value):
+        return (_('The value "%(pvalue)s" of property "%(pname)s" must be '
+                  'greater than "%(cvalue)s".') %
+                dict(pname=self.property_name,
+                     pvalue=self.value_msg,
+                     cvalue=self.constraint_value_msg))
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/InRange.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/InRange.java
new file mode 100644
index 0000000..282267d
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/InRange.java
@@ -0,0 +1,171 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.Date;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+import java.util.ArrayList;
+
+public class InRange extends Constraint {
+    // Constraint class for "in_range"
+
+    //Constrains a property or parameter to a value in range of (inclusive)
+    //the two values declared.
+
+    private static final String UNBOUNDED = "UNBOUNDED";
+    
+    private Object min,max;
+
+	protected void _setValues() {
+
+		constraintKey = IN_RANGE;
+
+		validTypes.add("Integer");
+		validTypes.add("Double");
+		validTypes.add("Float");
+		validTypes.add("String");
+		// timestamps are loaded as Date objects
+		validTypes.add("Date");
+		//validTypes.add("datetime.date");
+		//validTypes.add("datetime.time");
+		//validTypes.add("datetime.datetime");
+		
+		validPropTypes.add(Schema.INTEGER);
+		validPropTypes.add(Schema.FLOAT);
+		validPropTypes.add(Schema.TIMESTAMP);
+		validPropTypes.add(Schema.SCALAR_UNIT_SIZE);
+		validPropTypes.add(Schema.SCALAR_UNIT_FREQUENCY);
+		validPropTypes.add(Schema.SCALAR_UNIT_TIME);
+		validPropTypes.add(Schema.RANGE);
+		
+	}
+	
+	@SuppressWarnings("unchecked")
+	public InRange(String name,String type,Object c) {
+		super(name,type,c);
+
+		if(!(constraintValue instanceof ArrayList) || ((ArrayList<Object>)constraintValue).size() != 2) {
+            ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: The property \"in_range\" expects a list");
+			
+		}
+
+		ArrayList<Object> alcv = (ArrayList<Object>)constraintValue;
+        String msg = "The property \"in_range\" expects comparable values";
+        for(Object vo: alcv) {
+    		if(!validTypes.contains(vo.getClass().getSimpleName())) {
+    	        ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: " + msg);
+    		}
+            // The only string we allow for range is the special value 'UNBOUNDED'
+            if((vo instanceof String) && !((String)vo).equals(UNBOUNDED)) { 
+				ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: " + msg);
+            }
+        }
+        min = alcv.get(0);
+        max = alcv.get(1);
+        
+	}
+
+	@Override
+	protected boolean _isValid(Object value) {
+		
+		// timestamps
+		if(value instanceof Date) {
+			if(min instanceof Date && max instanceof Date) {
+				return !((Date)value).before((Date)min) &&
+					   !((Date)value).after((Date)max);
+			}
+			return false;
+		}
+
+		Double dvalue = new Double(value.toString());
+        if(!(min instanceof String)) {
+            if(dvalue < new Double(min.toString())) {
+                return false;
+            }
+        }
+        else if(!((String)min).equals(UNBOUNDED)) {
+            return false;
+        }
+        if(!(max instanceof String)) {
+            if(dvalue > new Double(max.toString())) {
+                return false;
+            }
+        }
+        else if(!((String)max).equals(UNBOUNDED)) {
+            return false;
+        }
+        return true;
+	}
+
+	@Override
+	protected String _errMsg(Object value) {
+        return String.format("The value \"%s\" of property \"%s\" is out of range \"(min:%s, max:%s)\"",
+        					valueMsg,propertyName,min.toString(),max.toString());
+	}
+
+}
+
+/*python
+
+class InRange(Constraint):
+    """Constraint class for "in_range"
+
+    Constrains a property or parameter to a value in range of (inclusive)
+    the two values declared.
+    """
+    UNBOUNDED = 'UNBOUNDED'
+
+    constraint_key = Constraint.IN_RANGE
+
+    valid_types = (int, float, datetime.date,
+                   datetime.time, datetime.datetime, str)
+
+    valid_prop_types = (Schema.INTEGER, Schema.FLOAT, Schema.TIMESTAMP,
+                        Schema.SCALAR_UNIT_SIZE, Schema.SCALAR_UNIT_FREQUENCY,
+                        Schema.SCALAR_UNIT_TIME, Schema.RANGE)
+
+    def __init__(self, property_name, property_type, constraint):
+        super(InRange, self).__init__(property_name, property_type, constraint)
+        if(not isinstance(self.constraint_value, collections.Sequence) or
+           (len(constraint[self.IN_RANGE]) != 2)):
+            ExceptionCollector.appendException(
+                InvalidSchemaError(message=_('The property "in_range" '
+                                             'expects a list.')))
+
+        msg = _('The property "in_range" expects comparable values.')
+        for value in self.constraint_value:
+            if not isinstance(value, self.valid_types):
+                ExceptionCollector.appendException(
+                    InvalidSchemaError(message=msg))
+            # The only string we allow for range is the special value
+            # 'UNBOUNDED'
+            if(isinstance(value, str) and value != self.UNBOUNDED):
+                ExceptionCollector.appendException(
+                    InvalidSchemaError(message=msg))
+
+        self.min = self.constraint_value[0]
+        self.max = self.constraint_value[1]
+
+    def _is_valid(self, value):
+        if not isinstance(self.min, str):
+            if value < self.min:
+                return False
+        elif self.min != self.UNBOUNDED:
+            return False
+        if not isinstance(self.max, str):
+            if value > self.max:
+                return False
+        elif self.max != self.UNBOUNDED:
+            return False
+        return True
+
+    def _err_msg(self, value):
+        return (_('The value "%(pvalue)s" of property "%(pname)s" is out of '
+                  'range "(min:%(vmin)s, max:%(vmax)s)".') %
+                dict(pname=self.property_name,
+                     pvalue=self.value_msg,
+                     vmin=self.constraint_value_msg[0],
+                     vmax=self.constraint_value_msg[1]))
+
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Length.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Length.java
new file mode 100644
index 0000000..4cfd1c0
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Length.java
@@ -0,0 +1,79 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class Length extends Constraint {
+	// Constraint class for "length"
+	
+	// Constrains the property or parameter to a value of a given length.
+
+	@Override
+	protected void _setValues() {
+
+		constraintKey = LENGTH;
+
+		validTypes.add("Integer");
+		
+		validPropTypes.add(Schema.STRING);
+		
+	}
+	
+	public Length(String name,String type,Object c) {
+		super(name,type,c);
+		
+		if(!validTypes.contains(constraintValue.getClass().getSimpleName())) {
+	        ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: The property \"length\" expects an integer");
+		}
+	}
+	
+	@Override
+	protected boolean _isValid(Object value) {
+	    if(value instanceof String && constraintValue instanceof Integer &&
+	    		((String)value).length() == (Integer)constraintValue) {
+	        return true;
+	    }
+		return false;
+	}
+
+	@Override
+	protected String _errMsg(Object value) {
+	    return String.format("Length of value \"%s\" of property \"%s\" must be equal to \"%s\"",
+	    					 value.toString(),propertyName,constraintValue.toString());
+	}
+
+}
+
+/*python
+	class Length(Constraint):
+	"""Constraint class for "length"
+	
+	Constrains the property or parameter to a value of a given length.
+	"""
+	
+	constraint_key = Constraint.LENGTH
+	
+	valid_types = (int, )
+	
+	valid_prop_types = (Schema.STRING, )
+	
+	def __init__(self, property_name, property_type, constraint):
+	    super(Length, self).__init__(property_name, property_type, constraint)
+	    if not isinstance(self.constraint_value, self.valid_types):
+	        ExceptionCollector.appendException(
+	            InvalidSchemaError(message=_('The property "length" expects '
+	                                         'an integer.')))
+	
+	def _is_valid(self, value):
+	    if isinstance(value, str) and len(value) == self.constraint_value:
+	        return True
+	
+	    return False
+	
+	def _err_msg(self, value):
+	    return (_('Length of value "%(pvalue)s" of property "%(pname)s" '
+	              'must be equal to "%(cvalue)s".') %
+	            dict(pname=self.property_name,
+	                 pvalue=value,
+	                 cvalue=self.constraint_value))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/LessOrEqual.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/LessOrEqual.java
new file mode 100644
index 0000000..00cba36
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/LessOrEqual.java
@@ -0,0 +1,106 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.Date;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class LessOrEqual extends Constraint {
+	// Constraint class for "less_or_equal"
+
+	// Constrains a property or parameter to a value less than or equal
+	// to ('<=') the value declared.
+
+	protected void _setValues() {
+
+		constraintKey = LESS_OR_EQUAL;
+
+		validTypes.add("Integer");
+		validTypes.add("Double");
+		validTypes.add("Float");
+		// timestamps are loaded as Date objects
+		validTypes.add("Date");
+		//validTypes.add("datetime.date");
+		//validTypes.add("datetime.time");
+		//validTypes.add("datetime.datetime");
+		
+		validPropTypes.add(Schema.INTEGER);
+		validPropTypes.add(Schema.FLOAT);
+		validPropTypes.add(Schema.TIMESTAMP);
+		validPropTypes.add(Schema.SCALAR_UNIT_SIZE);
+		validPropTypes.add(Schema.SCALAR_UNIT_FREQUENCY);
+		validPropTypes.add(Schema.SCALAR_UNIT_TIME);
+		
+	}
+	
+	public LessOrEqual(String name,String type,Object c) {
+		super(name,type,c);
+		
+		if(!validTypes.contains(constraintValue.getClass().getSimpleName())) {
+	        ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: The property \"less_or_equal\" expects comparable values");
+		}
+	}
+	
+	@Override
+	protected boolean _isValid(Object value) {
+
+		// timestamps
+	    if(value instanceof Date) {
+	    	if(constraintValue instanceof Date) {
+	    		return !((Date)value).after((Date)constraintValue);
+	    	}
+	    	return false;
+	    }
+	    
+		Double n1 = new Double(value.toString());
+		Double n2 = new Double(constraintValue.toString());
+		return n1 <= n2;
+	}
+
+	@Override
+	protected String _errMsg(Object value) {
+	    return String.format("The value \"%s\" of property \"%s\" must be less or equal to \"%s\"",
+	    		valueMsg,propertyName,constraintValueMsg);
+	}
+
+}
+
+/*python
+
+class LessOrEqual(Constraint):
+    """Constraint class for "less_or_equal"
+
+    Constrains a property or parameter to a value less than or equal
+    to ('<=') the value declared.
+    """
+
+    constraint_key = Constraint.LESS_OR_EQUAL
+
+    valid_types = (int, float, datetime.date,
+                   datetime.time, datetime.datetime)
+
+    valid_prop_types = (Schema.INTEGER, Schema.FLOAT, Schema.TIMESTAMP,
+                        Schema.SCALAR_UNIT_SIZE, Schema.SCALAR_UNIT_FREQUENCY,
+                        Schema.SCALAR_UNIT_TIME)
+
+    def __init__(self, property_name, property_type, constraint):
+        super(LessOrEqual, self).__init__(property_name, property_type,
+                                          constraint)
+        if not isinstance(self.constraint_value, self.valid_types):
+            ExceptionCollector.appendException(
+                InvalidSchemaError(message=_('The property "less_or_equal" '
+                                             'expects comparable values.')))
+
+    def _is_valid(self, value):
+        if value <= self.constraint_value:
+            return True
+
+        return False
+
+    def _err_msg(self, value):
+        return (_('The value "%(pvalue)s" of property "%(pname)s" must be '
+                  'less than or equal to "%(cvalue)s".') %
+                dict(pname=self.property_name,
+                     pvalue=self.value_msg,
+                     cvalue=self.constraint_value_msg))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/LessThan.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/LessThan.java
new file mode 100644
index 0000000..eb5a41d
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/LessThan.java
@@ -0,0 +1,104 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.Date;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class LessThan extends Constraint {
+
+	@Override
+	protected void _setValues() {
+
+		constraintKey = LESS_THAN;
+
+		validTypes.add("Integer");
+		validTypes.add("Double");
+		validTypes.add("Float");
+		// timestamps are loaded as Date objects
+		validTypes.add("Date");
+		//validTypes.add("datetime.date");
+		//validTypes.add("datetime.time");
+		//validTypes.add("datetime.datetime");
+		
+		
+		validPropTypes.add(Schema.INTEGER);
+		validPropTypes.add(Schema.FLOAT);
+		validPropTypes.add(Schema.TIMESTAMP);
+		validPropTypes.add(Schema.SCALAR_UNIT_SIZE);
+		validPropTypes.add(Schema.SCALAR_UNIT_FREQUENCY);
+		validPropTypes.add(Schema.SCALAR_UNIT_TIME);
+		
+	}
+	
+	public LessThan(String name,String type,Object c) {
+		super(name,type,c);
+		
+		if(!validTypes.contains(constraintValue.getClass().getSimpleName())) {
+	        ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: The property \"less_than\" expects comparable values");
+		}
+	}
+	
+	@Override
+	protected boolean _isValid(Object value) {
+		
+	    // timestamps
+	    if(value instanceof Date) {
+	    	if(constraintValue instanceof Date) {
+	    		return ((Date)value).before((Date)constraintValue);
+	    	}
+	    	return false;
+	    }
+	    
+		Double n1 = new Double(value.toString());
+		Double n2 = new Double(constraintValue.toString());
+		return n1 < n2;
+	}
+
+	@Override
+	protected String _errMsg(Object value) {
+	    return String.format("The value \"%s\" of property \"%s\" must be less than \"%s\"",
+	    		valueMsg,propertyName,constraintValueMsg);
+	}
+
+}
+
+/*python
+
+class LessThan(Constraint):
+"""Constraint class for "less_than"
+
+Constrains a property or parameter to a value less than ('<')
+the value declared.
+"""
+
+constraint_key = Constraint.LESS_THAN
+
+valid_types = (int, float, datetime.date,
+               datetime.time, datetime.datetime)
+
+valid_prop_types = (Schema.INTEGER, Schema.FLOAT, Schema.TIMESTAMP,
+                    Schema.SCALAR_UNIT_SIZE, Schema.SCALAR_UNIT_FREQUENCY,
+                    Schema.SCALAR_UNIT_TIME)
+
+def __init__(self, property_name, property_type, constraint):
+    super(LessThan, self).__init__(property_name, property_type,
+                                   constraint)
+    if not isinstance(self.constraint_value, self.valid_types):
+        ExceptionCollector.appendException(
+            InvalidSchemaError(message=_('The property "less_than" '
+                                         'expects comparable values.')))
+
+def _is_valid(self, value):
+    if value < self.constraint_value:
+        return True
+
+    return False
+
+def _err_msg(self, value):
+    return (_('The value "%(pvalue)s" of property "%(pname)s" must be '
+              'less than "%(cvalue)s".') %
+            dict(pname=self.property_name,
+                 pvalue=self.value_msg,
+                 cvalue=self.constraint_value_msg))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/MaxLength.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/MaxLength.java
new file mode 100644
index 0000000..278ae85
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/MaxLength.java
@@ -0,0 +1,90 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class MaxLength extends Constraint {
+	// Constraint class for "min_length"
+	
+	// Constrains the property or parameter to a value of a maximum length.
+
+	@Override
+	protected void _setValues() {
+
+		constraintKey = MAX_LENGTH;
+
+		validTypes.add("Integer");
+		
+		validPropTypes.add(Schema.STRING);
+		validPropTypes.add(Schema.MAP);
+		
+	}
+	
+	public MaxLength(String name,String type,Object c) {
+		super(name,type,c);
+		
+		if(!validTypes.contains(constraintValue.getClass().getSimpleName())) {
+	        ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: The property \"max_length\" expects an integer");
+		}
+	}
+	
+	@SuppressWarnings("unchecked")
+	@Override
+	protected boolean _isValid(Object value) {
+	    if(value instanceof String && constraintValue instanceof Integer &&
+	    		((String)value).length() <= (Integer)constraintValue) {
+	        return true;
+	    }
+	    else if(value instanceof LinkedHashMap && constraintValue instanceof Integer &&
+	    		((LinkedHashMap<String,Object>)value).size() <= (Integer)constraintValue) {
+	        return true;
+	    }
+		return false;
+	}
+
+	@Override
+	protected String _errMsg(Object value) {
+	    return String.format("Length of value \"%s\" of property \"%s\" must be no greater than \"%s\"",
+	    					 value.toString(),propertyName,constraintValue.toString());
+	}
+
+}
+
+/*python
+
+class MaxLength(Constraint):
+    """Constraint class for "max_length"
+
+    Constrains the property or parameter to a value to a maximum length.
+    """
+
+    constraint_key = Constraint.MAX_LENGTH
+
+    valid_types = (int, )
+
+    valid_prop_types = (Schema.STRING, Schema.MAP)
+
+    def __init__(self, property_name, property_type, constraint):
+        super(MaxLength, self).__init__(property_name, property_type,
+                                        constraint)
+        if not isinstance(self.constraint_value, self.valid_types):
+            ExceptionCollector.appendException(
+                InvalidSchemaError(message=_('The property "max_length" '
+                                             'expects an integer.')))
+
+    def _is_valid(self, value):
+        if ((isinstance(value, str) or isinstance(value, dict)) and
+           len(value) <= self.constraint_value):
+            return True
+
+        return False
+
+    def _err_msg(self, value):
+        return (_('Length of value "%(pvalue)s" of property "%(pname)s" '
+                  'must be no greater than "%(cvalue)s".') %
+                dict(pname=self.property_name,
+                     pvalue=value,
+                     cvalue=self.constraint_value))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/MinLength.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/MinLength.java
new file mode 100644
index 0000000..480c878
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/MinLength.java
@@ -0,0 +1,90 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class MinLength extends Constraint {
+	// Constraint class for "min_length"
+	
+	// Constrains the property or parameter to a value of a minimum length.
+
+	@Override
+	protected void _setValues() {
+
+		constraintKey = MIN_LENGTH;
+
+		validTypes.add("Integer");
+		
+		validPropTypes.add(Schema.STRING);
+		validPropTypes.add(Schema.MAP);
+		
+	}
+	
+	public MinLength(String name,String type,Object c) {
+		super(name,type,c);
+		
+		if(!validTypes.contains(constraintValue.getClass().getSimpleName())) {
+	        ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: The property \"min_length\" expects an integer");
+		}
+	}
+	
+	@SuppressWarnings("unchecked")
+	@Override
+	protected boolean _isValid(Object value) {
+	    if(value instanceof String && constraintValue instanceof Integer &&
+	    		((String)value).length() >= (Integer)constraintValue) {
+	        return true;
+	    }
+	    else if(value instanceof LinkedHashMap && constraintValue instanceof Integer &&
+	    		((LinkedHashMap<String,Object>)value).size() >= (Integer)constraintValue) {
+	        return true;
+	    }
+		return false;
+	}
+
+	@Override
+	protected String _errMsg(Object value) {
+	    return String.format("Length of value \"%s\" of property \"%s\" must be at least \"%s\"",
+	    					 value.toString(),propertyName,constraintValue.toString());
+	}
+
+}
+
+/*python
+
+class MinLength(Constraint):
+	"""Constraint class for "min_length"
+	
+	Constrains the property or parameter to a value to a minimum length.
+	"""
+	
+	constraint_key = Constraint.MIN_LENGTH
+	
+	valid_types = (int, )
+	
+	valid_prop_types = (Schema.STRING, Schema.MAP)
+	
+	def __init__(self, property_name, property_type, constraint):
+	    super(MinLength, self).__init__(property_name, property_type,
+	                                    constraint)
+	    if not isinstance(self.constraint_value, self.valid_types):
+	        ExceptionCollector.appendException(
+	            InvalidSchemaError(message=_('The property "min_length" '
+	                                         'expects an integer.')))
+	
+	def _is_valid(self, value):
+	    if ((isinstance(value, str) or isinstance(value, dict)) and
+	       len(value) >= self.constraint_value):
+	        return True
+	
+	    return False
+	
+	def _err_msg(self, value):
+	    return (_('Length of value "%(pvalue)s" of property "%(pname)s" '
+	              'must be at least "%(cvalue)s".') %
+	            dict(pname=self.property_name,
+	                 pvalue=value,
+	                 cvalue=self.constraint_value))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Pattern.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Pattern.java
new file mode 100644
index 0000000..444a73c
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Pattern.java
@@ -0,0 +1,96 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.regex.Matcher;
+import java.util.regex.PatternSyntaxException;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class Pattern extends Constraint {
+
+	@Override
+	protected void _setValues() {
+
+		constraintKey = PATTERN;
+
+		validTypes.add("String");
+		
+		validPropTypes.add(Schema.STRING);
+		
+	}
+	
+	
+	public Pattern(String name,String type,Object c) {
+		super(name,type,c);
+		
+		if(!validTypes.contains(constraintValue.getClass().getSimpleName())) {
+	        ThreadLocalsHolder.getCollector().appendException("InvalidSchemaError: The property \"pattern\" expects a string");
+		}
+	}
+
+	@Override
+	protected boolean _isValid(Object value) {
+		try {
+			if(!(value instanceof String)) {
+		        ThreadLocalsHolder.getCollector().appendException(String.format("ValueError: Input value \"%s\" to \"pattern\" property \"%s\" must be a string",
+		        		value.toString(),propertyName));
+				return false;
+			}
+			String strp = constraintValue.toString();
+			String strm = value.toString();
+			java.util.regex.Pattern pattern = java.util.regex.Pattern.compile(strp);
+			Matcher matcher = pattern.matcher(strm);
+			if(matcher.find() && matcher.end() == strm.length()) {
+				return true;
+			}
+			return false;
+		}
+		catch(PatternSyntaxException pse) {
+	        ThreadLocalsHolder.getCollector().appendException(String.format("ValueError: Invalid regex \"%s\" in \"pattern\" property \"%s\"",
+	        		constraintValue.toString(),propertyName));
+	        return false;
+		}
+	}
+
+	@Override
+	protected String _errMsg(Object value) {
+	    return String.format("The value \"%s\" of property \"%s\" does not match the pattern \"%s\"",
+				 value.toString(),propertyName,constraintValue.toString());
+	}
+
+}
+
+/*python
+
+class Pattern(Constraint):
+    """Constraint class for "pattern"
+
+    Constrains the property or parameter to a value that is allowed by
+    the provided regular expression.
+    """
+
+    constraint_key = Constraint.PATTERN
+
+    valid_types = (str, )
+
+    valid_prop_types = (Schema.STRING, )
+
+    def __init__(self, property_name, property_type, constraint):
+        super(Pattern, self).__init__(property_name, property_type, constraint)
+        if not isinstance(self.constraint_value, self.valid_types):
+            ExceptionCollector.appendException(
+                InvalidSchemaError(message=_('The property "pattern" '
+                                             'expects a string.')))
+        self.match = re.compile(self.constraint_value).match
+
+    def _is_valid(self, value):
+        match = self.match(value)
+        return match is not None and match.end() == len(value)
+
+    def _err_msg(self, value):
+        return (_('The value "%(pvalue)s" of property "%(pname)s" does not '
+                  'match pattern "%(cvalue)s".') %
+                dict(pname=self.property_name,
+                     pvalue=value,
+                     cvalue=self.constraint_value))
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Schema.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Schema.java
new file mode 100644
index 0000000..ca721e6
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Schema.java
@@ -0,0 +1,278 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+
+public class Schema {
+
+	private static final String TYPE = "type";
+	private static final String REQUIRED = "required";
+	private static final String DESCRIPTION = "description";
+	private static final String DEFAULT = "default";
+	private static final String CONSTRAINTS = "constraints";
+	private static final String STATUS = "status";
+	private static final String ENTRYSCHEMA = "entry_schema";
+	private static final String KEYS[] = {
+	        TYPE, REQUIRED, DESCRIPTION,DEFAULT, CONSTRAINTS, ENTRYSCHEMA, STATUS};
+
+	public static final String INTEGER = "integer";
+	public static final String STRING = "string";
+	public static final String BOOLEAN = "boolean";
+	public static final String FLOAT = "float";
+	public static final String RANGE = "range";
+	public static final String NUMBER = "number";
+	public static final String TIMESTAMP = "timestamp";
+	public static final String LIST = "list";
+	public static final String MAP = "map";
+	public static final String SCALAR_UNIT_SIZE = "scalar-unit.size";
+	public static final String SCALAR_UNIT_FREQUENCY = "scalar-unit.frequency";
+	public static final String SCALAR_UNIT_TIME = "scalar-unit.time";
+	public static final String VERSION = "version";
+	public static final String PORTDEF = "PortDef";
+	public static final String PORTSPEC = "PortSpec"; //??? PortSpec.SHORTNAME
+	public static final String JSON = "json"; 
+
+	public static final String PROPERTY_TYPES[] = {
+	        INTEGER, STRING, BOOLEAN, FLOAT, RANGE,NUMBER, TIMESTAMP, LIST, MAP,
+	        SCALAR_UNIT_SIZE, SCALAR_UNIT_FREQUENCY, SCALAR_UNIT_TIME,
+	        VERSION, PORTDEF, PORTSPEC, JSON};
+	
+	@SuppressWarnings("unused")
+	private static final String SCALAR_UNIT_SIZE_DEFAULT = "B";
+	
+	private static Map<String,Long> SCALAR_UNIT_SIZE_DICT = new HashMap<>();
+	static {
+		SCALAR_UNIT_SIZE_DICT.put("B", 1L);
+		SCALAR_UNIT_SIZE_DICT.put("KB", 1000L);
+		SCALAR_UNIT_SIZE_DICT.put("KIB", 1024L);
+		SCALAR_UNIT_SIZE_DICT.put("MB", 1000000L);
+		SCALAR_UNIT_SIZE_DICT.put("MIB", 1048576L);
+		SCALAR_UNIT_SIZE_DICT.put("GB", 1000000000L);
+		SCALAR_UNIT_SIZE_DICT.put("GIB", 1073741824L);
+		SCALAR_UNIT_SIZE_DICT.put("TB", 1000000000000L);
+		SCALAR_UNIT_SIZE_DICT.put("TIB", 1099511627776L);
+	}
+	
+	private String name;
+	private LinkedHashMap<String,Object> schema;
+	private int _len;
+	private ArrayList<Constraint> constraintsList;
+
+ 
+	public Schema(String _name,LinkedHashMap<String,Object> _schemaDict) {
+		name = _name;
+		
+        if(!(_schemaDict instanceof LinkedHashMap)) {
+            //msg = (_('Schema definition of "%(pname)s" must be a dict.')
+            //       % dict(pname=name))
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+            		"InvalidSchemaError: Schema definition of \"%s\" must be a dict",name));
+        }
+
+        if(_schemaDict.get("type") == null) {
+            //msg = (_('Schema definition of "%(pname)s" must have a "type" '
+            //         'attribute.') % dict(pname=name))
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+            		"InvalidSchemaError: Schema definition of \"%s\" must have a \"type\" attribute",name));
+        }
+        
+        schema = _schemaDict;
+        _len = 0; //??? None
+        constraintsList = new ArrayList<>();
+	}
+
+    public String getType() {
+        return (String)schema.get(TYPE);
+    }
+
+    public boolean isRequired() {
+        return (boolean)schema.getOrDefault(REQUIRED, true);
+    }
+
+    public String getDescription() {
+        return (String)schema.getOrDefault(DESCRIPTION,"");
+    }
+
+    public Object getDefault() {
+        return schema.get(DEFAULT);
+    }
+
+    public String getStatus() {
+        return (String)schema.getOrDefault(STATUS,"");
+    }
+
+    @SuppressWarnings("unchecked")
+	public ArrayList<Constraint> getConstraints() {
+        if(constraintsList.size() == 0) {
+        	Object cob = schema.get(CONSTRAINTS);
+        	if(cob instanceof ArrayList) {
+				ArrayList<Object> constraintSchemata = (ArrayList<Object>)cob;
+            	for(Object ob: constraintSchemata) {
+            		if(ob instanceof LinkedHashMap) {
+	            		for(String cClass: ((LinkedHashMap<String,Object>)ob).keySet()) {
+	            			Constraint c = Constraint.factory(cClass,name,getType(),ob);
+	            			if(c != null) {
+	            				constraintsList.add(c);
+	            			}
+	            			else {
+	            				// error
+	            				ThreadLocalsHolder.getCollector().appendException(String.format(
+	            					"UnknownFieldError: Constraint type \"%s\" for property \"%s\" is not supported",
+	            					cClass,name));
+	            			}
+	            			break;
+	            		}
+            		}
+            	}
+        	}
+        }
+        return constraintsList;
+    }
+
+    @SuppressWarnings("unchecked")
+	public LinkedHashMap<String,Object> getEntrySchema() {
+        return (LinkedHashMap<String,Object>)schema.get(ENTRYSCHEMA);
+    }
+    
+    // Python intrinsic methods...
+
+    // substitute for __getitem__ (aka self[key])
+    public Object getItem(String key) {
+    	return schema.get(key);
+    }
+    
+    /*
+    def __iter__(self):
+        for k in self.KEYS:
+            try:
+                self.schema[k]
+            except KeyError:
+                pass
+            else:
+                yield k
+    */
+    
+    // substitute for __len__ (aka self.len())
+    public int getLen() {
+    	int len = 0;
+    	for(String k: KEYS) {
+    		if(schema.get(k) != null) {
+    			len++;
+    		}
+    		_len = len;
+    	}
+    	return _len;
+    }
+    // getter
+    public LinkedHashMap<String,Object> getSchema() {
+    	return schema;
+    }
+    
+}
+
+/*python
+
+class Schema(collections.Mapping):
+
+KEYS = (
+    TYPE, REQUIRED, DESCRIPTION,
+    DEFAULT, CONSTRAINTS, ENTRYSCHEMA, STATUS
+) = (
+    'type', 'required', 'description',
+    'default', 'constraints', 'entry_schema', 'status'
+)
+
+PROPERTY_TYPES = (
+    INTEGER, STRING, BOOLEAN, FLOAT, RANGE,
+    NUMBER, TIMESTAMP, LIST, MAP,
+    SCALAR_UNIT_SIZE, SCALAR_UNIT_FREQUENCY, SCALAR_UNIT_TIME,
+    VERSION, PORTDEF, PORTSPEC
+) = (
+    'integer', 'string', 'boolean', 'float', 'range',
+    'number', 'timestamp', 'list', 'map',
+    'scalar-unit.size', 'scalar-unit.frequency', 'scalar-unit.time',
+    'version', 'PortDef', PortSpec.SHORTNAME
+)
+
+SCALAR_UNIT_SIZE_DEFAULT = 'B'
+SCALAR_UNIT_SIZE_DICT = {'B': 1, 'KB': 1000, 'KIB': 1024, 'MB': 1000000,
+                         'MIB': 1048576, 'GB': 1000000000,
+                         'GIB': 1073741824, 'TB': 1000000000000,
+                         'TIB': 1099511627776}
+
+def __init__(self, name, schema_dict):
+    self.name = name
+    if not isinstance(schema_dict, collections.Mapping):
+        msg = (_('Schema definition of "%(pname)s" must be a dict.')
+               % dict(pname=name))
+        ExceptionCollector.appendException(InvalidSchemaError(message=msg))
+
+    try:
+        schema_dict['type']
+    except KeyError:
+        msg = (_('Schema definition of "%(pname)s" must have a "type" '
+                 'attribute.') % dict(pname=name))
+        ExceptionCollector.appendException(InvalidSchemaError(message=msg))
+
+    self.schema = schema_dict
+    self._len = None
+    self.constraints_list = []
+
+@property
+def type(self):
+    return self.schema[self.TYPE]
+
+@property
+def required(self):
+    return self.schema.get(self.REQUIRED, True)
+
+@property
+def description(self):
+    return self.schema.get(self.DESCRIPTION, '')
+
+@property
+def default(self):
+    return self.schema.get(self.DEFAULT)
+
+@property
+def status(self):
+    return self.schema.get(self.STATUS, '')
+
+@property
+def constraints(self):
+    if not self.constraints_list:
+        constraint_schemata = self.schema.get(self.CONSTRAINTS)
+        if constraint_schemata:
+            self.constraints_list = [Constraint(self.name,
+                                                self.type,
+                                                cschema)
+                                     for cschema in constraint_schemata]
+    return self.constraints_list
+
+@property
+def entry_schema(self):
+    return self.schema.get(self.ENTRYSCHEMA)
+
+def __getitem__(self, key):
+    return self.schema[key]
+
+def __iter__(self):
+    for k in self.KEYS:
+        try:
+            self.schema[k]
+        except KeyError:
+            pass
+        else:
+            yield k
+
+def __len__(self):
+    if self._len is None:
+        self._len = len(list(iter(self)))
+    return self._len
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Schema.java.orig b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Schema.java.orig
new file mode 100644
index 0000000..96eff34
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/Schema.java.orig
@@ -0,0 +1,281 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+
+
+public class Schema {
+
+	private static final String TYPE = "type";
+	private static final String REQUIRED = "required";
+	private static final String DESCRIPTION = "description";
+	private static final String DEFAULT = "default";
+	private static final String CONSTRAINTS = "constraints";
+	private static final String STATUS = "status";
+	private static final String ENTRYSCHEMA = "entry_schema";
+	private static final String KEYS[] = {
+	        TYPE, REQUIRED, DESCRIPTION,DEFAULT, CONSTRAINTS, ENTRYSCHEMA, STATUS};
+
+	public static final String INTEGER = "integer";
+	public static final String STRING = "string";
+	public static final String BOOLEAN = "boolean";
+	public static final String FLOAT = "float";
+	public static final String RANGE = "range";
+	public static final String NUMBER = "number";
+	public static final String TIMESTAMP = "timestamp";
+	public static final String LIST = "list";
+	public static final String MAP = "map";
+	public static final String SCALAR_UNIT_SIZE = "scalar-unit.size";
+	public static final String SCALAR_UNIT_FREQUENCY = "scalar-unit.frequency";
+	public static final String SCALAR_UNIT_TIME = "scalar-unit.time";
+	public static final String VERSION = "version";
+	public static final String PORTDEF = "PortDef";
+	public static final String PORTSPEC = "PortSpec"; //??? PortSpec.SHORTNAME
+<<<<<<< HEAD
+	public static final String JSON = "json"; 
+=======
+	public static final String JSON = "json";
+>>>>>>> master
+
+	public static final String PROPERTY_TYPES[] = {
+	        INTEGER, STRING, BOOLEAN, FLOAT, RANGE,NUMBER, TIMESTAMP, LIST, MAP,
+	        SCALAR_UNIT_SIZE, SCALAR_UNIT_FREQUENCY, SCALAR_UNIT_TIME,
+	        VERSION, PORTDEF, PORTSPEC, JSON};
+	
+	@SuppressWarnings("unused")
+	private static final String SCALAR_UNIT_SIZE_DEFAULT = "B";
+	
+	private static Map<String,Long> SCALAR_UNIT_SIZE_DICT = new HashMap<>();
+	static {
+		SCALAR_UNIT_SIZE_DICT.put("B", 1L);
+		SCALAR_UNIT_SIZE_DICT.put("KB", 1000L);
+		SCALAR_UNIT_SIZE_DICT.put("KIB", 1024L);
+		SCALAR_UNIT_SIZE_DICT.put("MB", 1000000L);
+		SCALAR_UNIT_SIZE_DICT.put("MIB", 1048576L);
+		SCALAR_UNIT_SIZE_DICT.put("GB", 1000000000L);
+		SCALAR_UNIT_SIZE_DICT.put("GIB", 1073741824L);
+		SCALAR_UNIT_SIZE_DICT.put("TB", 1000000000000L);
+		SCALAR_UNIT_SIZE_DICT.put("TIB", 1099511627776L);
+	}
+	
+	private String name;
+	private LinkedHashMap<String,Object> schema;
+	private int _len;
+	private ArrayList<Constraint> constraintsList;
+
+ 
+	public Schema(String _name,LinkedHashMap<String,Object> _schemaDict) {
+		name = _name;
+		
+        if(!(_schemaDict instanceof LinkedHashMap)) {
+            //msg = (_('Schema definition of "%(pname)s" must be a dict.')
+            //       % dict(pname=name))
+            ExceptionCollector.appendException(String.format(
+            		"InvalidSchemaError: Schema definition of \"%s\" must be a dict",name));
+        }
+
+        if(_schemaDict.get("type") == null) {
+            //msg = (_('Schema definition of "%(pname)s" must have a "type" '
+            //         'attribute.') % dict(pname=name))
+            ExceptionCollector.appendException(String.format(
+            		"InvalidSchemaError: Schema definition of \"%s\" must have a \"type\" attribute",name));
+        }
+        
+        schema = _schemaDict;
+        _len = 0; //??? None
+        constraintsList = new ArrayList<>();
+	}
+
+    public String getType() {
+        return (String)schema.get(TYPE);
+    }
+
+    public boolean isRequired() {
+        return (boolean)schema.getOrDefault(REQUIRED, true);
+    }
+
+    public String getDescription() {
+        return (String)schema.getOrDefault(DESCRIPTION,"");
+    }
+
+    public Object getDefault() {
+        return schema.get(DEFAULT);
+    }
+
+    public String getStatus() {
+        return (String)schema.getOrDefault(STATUS,"");
+    }
+
+    @SuppressWarnings("unchecked")
+	public ArrayList<Constraint> getConstraints() {
+        if(constraintsList.size() == 0) {
+        	Object cob = schema.get(CONSTRAINTS);
+        	if(cob instanceof ArrayList) {
+				ArrayList<Object> constraintSchemata = (ArrayList<Object>)cob;
+            	for(Object ob: constraintSchemata) {
+            		if(ob instanceof LinkedHashMap) {
+	            		for(String cClass: ((LinkedHashMap<String,Object>)ob).keySet()) {
+	            			Constraint c = Constraint.factory(cClass,name,getType(),ob);
+	            			if(c != null) {
+	            				constraintsList.add(c);
+	            			}
+	            			else {
+	            				// error
+	            				ExceptionCollector.appendException(String.format(
+	            					"UnknownFieldError: Constraint type \"%s\" for property \"%s\" is not supported",
+	            					cClass,name));
+	            			}
+	            			break;
+	            		}
+            		}
+            	}
+        	}
+        }
+        return constraintsList;
+    }
+
+    @SuppressWarnings("unchecked")
+	public LinkedHashMap<String,Object> getEntrySchema() {
+        return (LinkedHashMap<String,Object>)schema.get(ENTRYSCHEMA);
+    }
+    
+    // Python intrinsic methods...
+
+    // substitute for __getitem__ (aka self[key])
+    public Object getItem(String key) {
+    	return schema.get(key);
+    }
+    
+    /*
+    def __iter__(self):
+        for k in self.KEYS:
+            try:
+                self.schema[k]
+            except KeyError:
+                pass
+            else:
+                yield k
+    */
+    
+    // substitute for __len__ (aka self.len())
+    public int getLen() {
+    	int len = 0;
+    	for(String k: KEYS) {
+    		if(schema.get(k) != null) {
+    			len++;
+    		}
+    		_len = len;
+    	}
+    	return _len;
+    }
+    // getter
+    public LinkedHashMap<String,Object> getSchema() {
+    	return schema;
+    }
+    
+}
+
+/*python
+
+class Schema(collections.Mapping):
+
+KEYS = (
+    TYPE, REQUIRED, DESCRIPTION,
+    DEFAULT, CONSTRAINTS, ENTRYSCHEMA, STATUS
+) = (
+    'type', 'required', 'description',
+    'default', 'constraints', 'entry_schema', 'status'
+)
+
+PROPERTY_TYPES = (
+    INTEGER, STRING, BOOLEAN, FLOAT, RANGE,
+    NUMBER, TIMESTAMP, LIST, MAP,
+    SCALAR_UNIT_SIZE, SCALAR_UNIT_FREQUENCY, SCALAR_UNIT_TIME,
+    VERSION, PORTDEF, PORTSPEC
+) = (
+    'integer', 'string', 'boolean', 'float', 'range',
+    'number', 'timestamp', 'list', 'map',
+    'scalar-unit.size', 'scalar-unit.frequency', 'scalar-unit.time',
+    'version', 'PortDef', PortSpec.SHORTNAME
+)
+
+SCALAR_UNIT_SIZE_DEFAULT = 'B'
+SCALAR_UNIT_SIZE_DICT = {'B': 1, 'KB': 1000, 'KIB': 1024, 'MB': 1000000,
+                         'MIB': 1048576, 'GB': 1000000000,
+                         'GIB': 1073741824, 'TB': 1000000000000,
+                         'TIB': 1099511627776}
+
+def __init__(self, name, schema_dict):
+    self.name = name
+    if not isinstance(schema_dict, collections.Mapping):
+        msg = (_('Schema definition of "%(pname)s" must be a dict.')
+               % dict(pname=name))
+        ExceptionCollector.appendException(InvalidSchemaError(message=msg))
+
+    try:
+        schema_dict['type']
+    except KeyError:
+        msg = (_('Schema definition of "%(pname)s" must have a "type" '
+                 'attribute.') % dict(pname=name))
+        ExceptionCollector.appendException(InvalidSchemaError(message=msg))
+
+    self.schema = schema_dict
+    self._len = None
+    self.constraints_list = []
+
+@property
+def type(self):
+    return self.schema[self.TYPE]
+
+@property
+def required(self):
+    return self.schema.get(self.REQUIRED, True)
+
+@property
+def description(self):
+    return self.schema.get(self.DESCRIPTION, '')
+
+@property
+def default(self):
+    return self.schema.get(self.DEFAULT)
+
+@property
+def status(self):
+    return self.schema.get(self.STATUS, '')
+
+@property
+def constraints(self):
+    if not self.constraints_list:
+        constraint_schemata = self.schema.get(self.CONSTRAINTS)
+        if constraint_schemata:
+            self.constraints_list = [Constraint(self.name,
+                                                self.type,
+                                                cschema)
+                                     for cschema in constraint_schemata]
+    return self.constraints_list
+
+@property
+def entry_schema(self):
+    return self.schema.get(self.ENTRYSCHEMA)
+
+def __getitem__(self, key):
+    return self.schema[key]
+
+def __iter__(self):
+    for k in self.KEYS:
+        try:
+            self.schema[k]
+        except KeyError:
+            pass
+        else:
+            yield k
+
+def __len__(self):
+    if self._len is None:
+        self._len = len(list(iter(self)))
+    return self._len
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/ValidValues.java b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/ValidValues.java
new file mode 100644
index 0000000..06622e4
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/elements/constraints/ValidValues.java
@@ -0,0 +1,84 @@
+package org.openecomp.sdc.toscaparser.api.elements.constraints;
+
+import java.util.ArrayList;
+
+public class ValidValues extends Constraint {
+
+
+	protected void _setValues() {
+
+		constraintKey = VALID_VALUES;
+		
+		for(String s: Schema.PROPERTY_TYPES) {
+			validPropTypes.add(s);
+		}
+		
+	}
+	
+	
+	public ValidValues(String name,String type,Object c) {
+		super(name,type,c);
+		
+	}
+
+    @SuppressWarnings("unchecked")
+	protected boolean _isValid(Object val) {
+    	if(!(constraintValue instanceof ArrayList)) {
+    		return false;
+    	}
+    	if(val instanceof ArrayList) {
+    		boolean bAll = true;
+    		for(Object v: (ArrayList<Object>)val) {
+    			if(!((ArrayList<Object>)constraintValue).contains(v)) {
+    				bAll = false;
+    				break;
+    			};
+    		}
+    		return bAll;
+    	}
+    	return ((ArrayList<Object>)constraintValue).contains(val);
+    }
+
+    protected String _errMsg(Object value) {
+    	return String.format("The value \"%s\" of property \"%s\" is not valid. Expected a value from \"%s\"",
+    			value.toString(),propertyName,constraintValue.toString());
+    }
+    
+}
+
+/*python
+
+class ValidValues(Constraint):
+"""Constraint class for "valid_values"
+
+Constrains a property or parameter to a value that is in the list of
+declared values.
+"""
+constraint_key = Constraint.VALID_VALUES
+
+valid_prop_types = Schema.PROPERTY_TYPES
+
+def __init__(self, property_name, property_type, constraint):
+    super(ValidValues, self).__init__(property_name, property_type,
+                                      constraint)
+    if not isinstance(self.constraint_value, collections.Sequence):
+        ExceptionCollector.appendException(
+            InvalidSchemaError(message=_('The property "valid_values" '
+                                         'expects a list.')))
+
+def _is_valid(self, value):
+    print '*** payton parser validating ',value,' in ',self.constraint_value#GGG
+    if isinstance(value, list):
+        return all(v in self.constraint_value for v in value)
+    return value in self.constraint_value
+
+def _err_msg(self, value):
+    allowed = '[%s]' % ', '.join(str(a) for a in self.constraint_value)
+    return (_('The value "%(pvalue)s" of property "%(pname)s" is not '
+              'valid. Expected a value from "%(cvalue)s".') %
+            dict(pname=self.property_name,
+                 pvalue=value,
+                 cvalue=allowed))
+
+
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/extensions/ExtTools.java b/src/main/java/org/openecomp/sdc/toscaparser/api/extensions/ExtTools.java
new file mode 100644
index 0000000..6403d6e
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/extensions/ExtTools.java
@@ -0,0 +1,210 @@
+package org.openecomp.sdc.toscaparser.api.extensions;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.nio.charset.Charset;
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class ExtTools {
+
+	private static Logger log = LoggerFactory.getLogger(ExtTools.class.getName());
+
+	private static LinkedHashMap<String,Object> EXTENSION_INFO = new LinkedHashMap<>();
+	
+	public ExtTools() {
+		
+        EXTENSION_INFO = _loadExtensions();
+	}
+	
+	private LinkedHashMap<String,Object> _loadExtensions() {
+		
+		LinkedHashMap<String,Object> extensions = new LinkedHashMap<>();
+		
+		String path = ExtTools.class.getProtectionDomain().getCodeSource().getLocation().getPath();
+	    //String extdir = path + File.separator + "resources/extensions";
+	    
+	    String extdir = ExtTools.class.getClassLoader().getResource("extensions").getFile();
+	    
+	    // for all folders in extdir
+	    File extDir = new File(extdir);
+	    File extDirList[] = extDir.listFiles();
+	    if (extDirList == null)  {
+	    	String a = "aaaa";
+	    	
+	    }
+	    if (extDirList != null) {
+		    for(File f: extDirList) {
+		    	if(f.isDirectory()) {
+		  	        // for all .py files in folder
+		    		File extFileList[] = f.listFiles();
+		    		for(File pyf: extFileList) {
+		    			String pyfName = pyf.getName();
+		    			String pyfPath = pyf.getAbsolutePath();
+		    			if(pyfName.endsWith(".py")) {
+		    				// get VERSION,SECTIONS,DEF_FILE
+		    				try {
+			    				String version = null;
+			    				ArrayList<String> sections = null;
+			    				String defsFile = null;
+		    				    String line;
+		    					InputStream fis = new FileInputStream(pyfPath);
+		    				    InputStreamReader isr = new InputStreamReader(fis, Charset.forName("UTF-8"));
+		    				    BufferedReader br = new BufferedReader(isr);
+		    					Pattern pattern = Pattern.compile("^([^#]\\S+)\\s*=\\s*(\\S.*)$");
+	    					    while((line = br.readLine()) != null) {
+		    					    line = line.replace("'","\"");
+	    	    					Matcher matcher = pattern.matcher(line.toString());
+	    	    					if(matcher.find()) {
+	    	    						if(matcher.group(1).equals("VERSION")) {
+	    	    							version = matcher.group(2);
+	    	    							if(version.startsWith("'") || version.startsWith("\"")) {
+	    	    								version = version.substring(1,version.length()-1);
+	    	    							}
+	    	    						}
+	    	    						else if(matcher.group(1).equals("DEFS_FILE")) {
+	    	    							String fn = matcher.group(2);
+	    	    							if(fn.startsWith("'") || fn.startsWith("\"")) {
+	    	    								fn = fn.substring(1,fn.length()-1);
+	    	    							}
+	    	    							defsFile = pyf.getParent() + File.separator + fn;//matcher.group(2);
+	    	    						}
+	    	    						else if(matcher.group(1).equals("SECTIONS")) {
+	    	    							sections = new ArrayList<>();
+	    	    							Pattern secpat = Pattern.compile("\"([^\"]+)\"");
+	    	    	    					Matcher secmat = secpat.matcher(matcher.group(2));
+	    	    	    					while(secmat.find()) {
+	    	    	    						sections.add(secmat.group(1));
+	    	    	    					}
+	    	    						}
+	    	    					}
+		    					}
+	    					    br.close();
+	    					    
+	    					    if(version != null && defsFile != null) {
+	    					    	LinkedHashMap<String,Object> ext = new LinkedHashMap<>();
+	    	    					ext.put("defs_file", defsFile);
+	    	    					if(sections != null) {
+	        	    					ext.put("sections", sections);
+	    	    					}
+	    	    					extensions.put(version, ext);
+		    					}
+	    					    else {
+	    					    	// error
+	    					    }
+		    				}
+		    				catch(Exception e) {
+		    					log.error("ExtTools - _loadExtensions - {}", e.getMessage());
+		    					// ...
+		    				}
+		    			}
+		    		}
+		    	}
+		    }
+	    }
+		return extensions;
+	}
+	
+	public ArrayList<String> getVersions() {
+		return new ArrayList<String>(EXTENSION_INFO.keySet());
+	}
+	
+	public LinkedHashMap<String,ArrayList<String>> getSections() {
+		LinkedHashMap<String,ArrayList<String>> sections = new LinkedHashMap<>();
+        for(String version: EXTENSION_INFO.keySet()) {
+        	LinkedHashMap<String,Object> eiv = (LinkedHashMap<String,Object>)EXTENSION_INFO.get(version);
+        	sections.put(version,(ArrayList<String>)eiv.get("sections"));
+        }
+        return sections;
+	}
+
+	public String getDefsFile(String version) { 
+    	LinkedHashMap<String,Object> eiv = (LinkedHashMap<String,Object>)EXTENSION_INFO.get(version);
+    	return (String)eiv.get("defs_file");
+	}
+	
+}
+
+/*python
+
+from toscaparser.common.exception import ToscaExtAttributeError
+from toscaparser.common.exception import ToscaExtImportError
+
+log = logging.getLogger("tosca.model")
+
+REQUIRED_ATTRIBUTES = ['VERSION', 'DEFS_FILE']
+
+
+class ExtTools(object):
+    def __init__(self):
+        self.EXTENSION_INFO = self._load_extensions()
+
+    def _load_extensions(self):
+        '''Dynamically load all the extensions .'''
+        extensions = {}
+
+        # Use the absolute path of the class path
+        abs_path = os.path.dirname(os.path.abspath(__file__))
+
+        extdirs = [e for e in os.listdir(abs_path) if
+                   not e.startswith('tests') and
+                   os.path.isdir(os.path.join(abs_path, e))]
+
+        for e in extdirs:
+            log.info(e)
+            extpath = abs_path + '/' + e
+            # Grab all the extension files in the given path
+            ext_files = [f for f in os.listdir(extpath) if f.endswith('.py')
+                         and not f.startswith('__init__')]
+
+            # For each module, pick out the target translation class
+            for f in ext_files:
+                log.info(f)
+                ext_name = 'toscaparser/extensions/' + e + '/' + f.strip('.py')
+                ext_name = ext_name.replace('/', '.')
+                try:
+                    extinfo = importlib.import_module(ext_name)
+                    version = getattr(extinfo, 'VERSION')
+                    defs_file = extpath + '/' + getattr(extinfo, 'DEFS_FILE')
+
+                    # Sections is an optional attribute
+                    sections = getattr(extinfo, 'SECTIONS', ())
+
+                    extensions[version] = {'sections': sections,
+                                           'defs_file': defs_file}
+                except ImportError:
+                    raise ToscaExtImportError(ext_name=ext_name)
+                except AttributeError:
+                    attrs = ', '.join(REQUIRED_ATTRIBUTES)
+                    raise ToscaExtAttributeError(ext_name=ext_name,
+                                                 attrs=attrs)
+
+        print 'Extensions ',extensions#GGG
+        return extensions
+
+    def get_versions(self):
+        return self.EXTENSION_INFO.keys()
+
+    def get_sections(self):
+        sections = {}
+        for version in self.EXTENSION_INFO.keys():
+            sections[version] = self.EXTENSION_INFO[version]['sections']
+
+        return sections
+
+    def get_defs_file(self, version):
+        versiondata = self.EXTENSION_INFO.get(version)
+
+        if versiondata:
+            return versiondata.get('defs_file')
+        else:
+            return None
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/functions/Concat.java b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/Concat.java
new file mode 100644
index 0000000..6dc7deb
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/Concat.java
@@ -0,0 +1,77 @@
+package org.openecomp.sdc.toscaparser.api.functions;
+
+import java.util.ArrayList;
+
+import org.openecomp.sdc.toscaparser.api.TopologyTemplate;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class Concat extends Function {
+    // Validate the function and provide an instance of the function
+
+    // Concatenation of values are supposed to be produced at runtime and
+    // therefore its the responsibility of the TOSCA engine to implement the
+    // evaluation of Concat functions.
+
+    // Arguments:
+
+    // * List of strings that needs to be concatenated
+
+    // Example:
+
+    //  [ 'http://',
+    //    get_attribute: [ server, public_address ],
+    //    ':' ,
+    //    get_attribute: [ server, port ] ]
+
+ 
+	public Concat(TopologyTemplate ttpl,Object context,String name,ArrayList<Object> args) {
+		super(ttpl,context,name,args);
+	}
+	
+	@Override
+	public Object result() {
+		return this;
+	}
+
+	@Override
+	void validate() {
+		if(args.size() < 1) {
+	        ThreadLocalsHolder.getCollector().appendException(
+	            "ValueError: Invalid arguments for function \"concat\". " +
+	            "Expected at least one argument");
+		}
+	}
+
+}
+
+/*python
+
+class Concat(Function):
+"""Validate the function and provide an instance of the function
+
+Concatenation of values are supposed to be produced at runtime and
+therefore its the responsibility of the TOSCA engine to implement the
+evaluation of Concat functions.
+
+Arguments:
+
+* List of strings that needs to be concatenated
+
+Example:
+
+  [ 'http://',
+    get_attribute: [ server, public_address ],
+    ':' ,
+    get_attribute: [ server, port ] ]
+"""
+
+def validate(self):
+    if len(self.args) < 1:
+        ExceptionCollector.appendException(
+            ValueError(_('Invalid arguments for function "{0}". Expected '
+                         'at least one arguments.').format(CONCAT)))
+
+def result(self):
+    return self
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/functions/Function.java b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/Function.java
new file mode 100644
index 0000000..102fbc0
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/Function.java
@@ -0,0 +1,191 @@
+package org.openecomp.sdc.toscaparser.api.functions;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.TopologyTemplate;
+
+public abstract class Function {
+
+	protected static final String GET_PROPERTY = "get_property";
+	protected static final String GET_ATTRIBUTE = "get_attribute";
+	protected static final String GET_INPUT = "get_input";
+	protected static final String GET_OPERATION_OUTPUT = "get_operation_output";
+	protected static final String CONCAT = "concat";
+	protected static final String TOKEN = "token";
+
+	protected static final String SELF = "SELF";
+	protected static final String HOST = "HOST";
+	protected static final String TARGET = "TARGET";
+	protected static final String SOURCE = "SOURCE";
+
+	protected static final String HOSTED_ON = "tosca.relationships.HostedOn";
+	
+	protected static HashMap<String,String> functionMappings = _getFunctionMappings();
+	
+	private static HashMap<String,String> _getFunctionMappings() {
+		HashMap<String,String> map = new HashMap<>();
+	    map.put(GET_PROPERTY,"GetProperty");
+	    map.put(GET_INPUT, "GetInput");
+	    map.put(GET_ATTRIBUTE, "GetAttribute");
+	    map.put(GET_OPERATION_OUTPUT, "GetOperationOutput");
+	    map.put(CONCAT, "Concat");
+	    map.put(TOKEN, "Token");
+	    return map;
+	}
+	
+	protected TopologyTemplate toscaTpl;
+	protected Object context;
+	protected String name;
+	protected ArrayList<Object> args;
+
+	
+	public Function(TopologyTemplate _toscaTpl,Object _context,String _name,ArrayList<Object> _args) {
+        toscaTpl = _toscaTpl;
+        context = _context;
+        name = _name;
+        args = _args;
+        validate();
+		
+	}
+	
+	abstract Object result();
+	
+	abstract void validate();
+
+	@SuppressWarnings("unchecked")
+	public static boolean isFunction(Object funcObj) {
+	    // Returns True if the provided function is a Tosca intrinsic function.
+		//
+	    //Examples:
+		//
+	    //* "{ get_property: { SELF, port } }"
+	    //* "{ get_input: db_name }"
+	    //* Function instance
+
+	    //:param function: Function as string or a Function instance.
+	    //:return: True if function is a Tosca intrinsic function, otherwise False.
+	    //
+		
+	    if(funcObj instanceof LinkedHashMap) {
+	    	LinkedHashMap<String,Object> function = (LinkedHashMap<String,Object>)funcObj;
+	    	if(function.size() == 1) {
+		        String funcName = (new ArrayList<String>(function.keySet())).get(0);
+		        return functionMappings.keySet().contains(funcName);
+	    	}
+	    }
+	    return (funcObj instanceof Function);
+	}
+	
+	@SuppressWarnings("unchecked")
+	public static Object getFunction(TopologyTemplate ttpl,Object context,Object rawFunctionObj) {
+	    // Gets a Function instance representing the provided template function.
+
+	    // If the format provided raw_function format is not relevant for template
+	    // functions or if the function name doesn't exist in function mapping the
+	    // method returns the provided raw_function.
+		//	
+	    // :param tosca_tpl: The tosca template.
+	    // :param node_template: The node template the function is specified for.
+	    // :param raw_function: The raw function as dict.
+	    // :return: Template function as Function instance or the raw_function if
+	    //  parsing was unsuccessful.
+		
+	    if(isFunction(rawFunctionObj)) {
+	        if(rawFunctionObj instanceof LinkedHashMap) {
+	        	LinkedHashMap<String,Object> rawFunction = (LinkedHashMap<String,Object>)rawFunctionObj;
+		        String funcName = (new ArrayList<String>(rawFunction.keySet())).get(0);
+		        if(functionMappings.keySet().contains(funcName)) {
+		        	String funcType = functionMappings.get(funcName);
+		        	Object oargs = (new ArrayList<Object>(rawFunction.values())).get(0);
+		        	ArrayList<Object> funcArgs;
+		        	if(oargs instanceof ArrayList) {
+		        		funcArgs = (ArrayList<Object>)oargs;
+		        	}
+		        	else {
+		        		funcArgs = new ArrayList<>();
+		        		funcArgs.add(oargs);
+		        	}
+
+		        	if(funcType.equals("GetInput")) {
+		        		return new GetInput(ttpl,context,funcName,funcArgs);
+		        	}
+		        	else if(funcType.equals("GetAttribute")) {
+		        		return new GetAttribute(ttpl,context,funcName,funcArgs);
+		        	} 
+		        	else if(funcType.equals("GetProperty")) {
+		        		return new GetProperty(ttpl,context,funcName,funcArgs);
+		        	} 
+		        	else if(funcType.equals("GetOperationOutput")) {
+		        		return new GetOperationOutput(ttpl,context,funcName,funcArgs);
+		        	} 
+		        	else if(funcType.equals("Concat")) {
+		        		return new Concat(ttpl,context,funcName,funcArgs);
+		        	} 
+		        	else if(funcType.equals("Token")) {
+		        		return new Token(ttpl,context,funcName,funcArgs);
+		        	} 
+		        }
+	        }
+	    }
+	    return rawFunctionObj;
+	}
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import UnknownInputError
+from toscaparser.dataentity import DataEntity
+from toscaparser.elements.constraints import Schema
+from toscaparser.elements.datatype import DataType
+from toscaparser.elements.entity_type import EntityType
+from toscaparser.elements.relationshiptype import RelationshipType
+from toscaparser.elements.statefulentitytype import StatefulEntityType
+from toscaparser.utils.gettextutils import _
+
+
+GET_PROPERTY = 'get_property'
+GET_ATTRIBUTE = 'get_attribute'
+GET_INPUT = 'get_input'
+GET_OPERATION_OUTPUT = 'get_operation_output'
+CONCAT = 'concat'
+TOKEN = 'token'
+
+SELF = 'SELF'
+HOST = 'HOST'
+TARGET = 'TARGET'
+SOURCE = 'SOURCE'
+
+HOSTED_ON = 'tosca.relationships.HostedOn'
+
+
+@six.add_metaclass(abc.ABCMeta)
+class Function(object):
+    """An abstract type for representing a Tosca template function."""
+
+    def __init__(self, tosca_tpl, context, name, args):
+        self.tosca_tpl = tosca_tpl
+        self.context = context
+        self.name = name
+        self.args = args
+        self.validate()
+
+    @abc.abstractmethod
+    def result(self):
+        """Invokes the function and returns its result
+
+        Some methods invocation may only be relevant on runtime (for example,
+        getting runtime properties) and therefore its the responsibility of
+        the orchestrator/translator to take care of such functions invocation.
+
+        :return: Function invocation result.
+        """
+        return {self.name: self.args}
+
+    @abc.abstractmethod
+    def validate(self):
+        """Validates function arguments."""
+        pass
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetAttribute.java b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetAttribute.java
new file mode 100644
index 0000000..549073b
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetAttribute.java
@@ -0,0 +1,535 @@
+package org.openecomp.sdc.toscaparser.api.functions;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.*;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.AttributeDef;
+import org.openecomp.sdc.toscaparser.api.elements.CapabilityTypeDef;
+import org.openecomp.sdc.toscaparser.api.elements.DataType;
+import org.openecomp.sdc.toscaparser.api.elements.EntityType;
+import org.openecomp.sdc.toscaparser.api.elements.NodeType;
+import org.openecomp.sdc.toscaparser.api.elements.PropertyDef;
+import org.openecomp.sdc.toscaparser.api.elements.RelationshipType;
+import org.openecomp.sdc.toscaparser.api.elements.StatefulEntityType;
+import org.openecomp.sdc.toscaparser.api.elements.constraints.Schema;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class GetAttribute extends Function {
+	// Get an attribute value of an entity defined in the service template
+
+	// Node template attributes values are set in runtime and therefore its the
+	// responsibility of the Tosca engine to implement the evaluation of
+	// get_attribute functions.
+
+	// Arguments:
+
+	// * Node template name | HOST.
+	// * Attribute name.
+
+	// If the HOST keyword is passed as the node template name argument the
+	// function will search each node template along the HostedOn relationship
+	// chain until a node which contains the attribute is found.
+
+	// Examples:
+
+	// * { get_attribute: [ server, private_address ] }
+	// * { get_attribute: [ HOST, private_address ] }
+	// * { get_attribute: [ HOST, private_address, 0 ] }
+	// * { get_attribute: [ HOST, private_address, 0, some_prop] }
+
+	public GetAttribute(TopologyTemplate ttpl,Object context,String name,ArrayList<Object> args) {
+		super(ttpl,context,name,args);
+	}
+	
+	@Override
+	void validate() {
+		if(args.size() < 2) {
+	        ThreadLocalsHolder.getCollector().appendException(
+			    "ValueError: Illegal arguments for function \"get_attribute\". Expected arguments: \"node-template-name\", \"req-or-cap\" (optional), \"property name.\"");
+		    return;
+		}
+		else if(args.size() == 2) {
+	        _findNodeTemplateContainingAttribute();
+		}
+	    else {
+	        NodeTemplate nodeTpl = _findNodeTemplate((String)args.get(0));
+	        if(nodeTpl == null) {
+	            return;
+	        }
+	        int index = 2;
+	        AttributeDef attr = nodeTpl.getTypeDefinition().getAttributeDefValue((String)args.get(1));
+	        if(attr != null) {
+	        	// found
+	        }
+	        else {
+	            index = 3;
+	            // then check the req or caps
+	            attr = _findReqOrCapAttribute((String)args.get(1),(String)args.get(2));
+	            if(attr == null) {
+	            	return;
+	            }
+	        }
+	        
+	        String valueType = (String)attr.getSchema().get("type");
+            if(args.size() > index) {
+	        	for(Object elem: args.subList(index,args.size())) {
+	        		if(valueType.equals("list")) {
+                        if(!(elem instanceof Integer)) {
+                            ThreadLocalsHolder.getCollector().appendException(String.format(
+                                "ValueError: Illegal arguments for function \"get_attribute\" \"%s\". Expected positive integer argument",
+                                elem.toString()));
+                        } 
+                        Object ob = attr.getSchema().get("entry_schema");
+                        valueType = (String)
+                        		((LinkedHashMap<String,Object>)ob).get("type");
+	        		}
+	        		else if(valueType.equals("map")) {
+                        Object ob = attr.getSchema().get("entry_schema");
+                        valueType = (String)
+                        		((LinkedHashMap<String,Object>)ob).get("type");
+	        		}
+	        		else {
+	        			boolean bFound = false;
+	        			for(String p: Schema.PROPERTY_TYPES) {
+	        				if(p.equals(valueType)) {
+	        					bFound = true;
+	        					break;
+	        				}
+	        			}
+	        			if(bFound) {
+	                        ThreadLocalsHolder.getCollector().appendException(String.format(
+	                            "ValueError: 'Illegal arguments for function \"get_attribute\". Unexpected attribute/index value \"%d\"",
+	                            elem));
+	                        return;
+	        			}
+	                    else {  // It is a complex type
+	                        DataType dataType = new DataType(valueType,null);
+	                        LinkedHashMap<String,PropertyDef> props = 
+	                        		dataType.getAllProperties();
+	                        PropertyDef prop = props.get((String)elem);
+	                        if(prop != null) {
+	                            valueType = (String)prop.getSchema().get("type");
+	                        }
+	                        else {
+	                            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                                "KeyError: Illegal arguments for function \"get_attribute\". Attribute name \"%s\" not found in \"%\"",
+	                                elem,valueType));
+	                        }
+	                    }
+	        		}
+	        	}
+            }
+	    }
+	}
+
+	@Override
+	public Object result() {
+		return this;
+	}
+
+	private NodeTemplate getReferencedNodeTemplate() {
+	    // Gets the NodeTemplate instance the get_attribute function refers to
+
+	    // If HOST keyword was used as the node template argument, the node
+	    // template which contains the attribute along the HostedOn relationship
+	    // chain will be returned.
+	    
+	    return _findNodeTemplateContainingAttribute();
+		
+	}
+
+	// Attributes can be explicitly created as part of the type definition
+	// or a property name can be implicitly used as an attribute name 
+	private NodeTemplate _findNodeTemplateContainingAttribute() {
+		NodeTemplate nodeTpl = _findNodeTemplate((String)args.get(0));
+		if(nodeTpl != null &&
+			!_attributeExistsInType(nodeTpl.getTypeDefinition()) &&
+			!nodeTpl.getProperties().keySet().contains(getAttributeName())) {
+	        ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "KeyError: Attribute \"%s\" was not found in node template \"%s\"",
+	            getAttributeName(),nodeTpl.getName()));
+		}
+	    return nodeTpl;
+	}
+
+	private boolean _attributeExistsInType(StatefulEntityType typeDefinition) {
+	    LinkedHashMap<String,AttributeDef> attrsDef = typeDefinition.getAttributesDef();
+	    return attrsDef.get(getAttributeName()) != null;
+	}
+
+	private NodeTemplate _findHostContainingAttribute(String nodeTemplateName) {
+		NodeTemplate nodeTemplate = _findNodeTemplate(nodeTemplateName);
+		if(nodeTemplate != null) {
+	        LinkedHashMap<String,Object> hostedOnRel = 
+	        		(LinkedHashMap<String,Object>)EntityType.TOSCA_DEF.get(HOSTED_ON);
+			for(Object ro: nodeTemplate.getRequirements()) {
+				if(ro != null && ro instanceof LinkedHashMap) {
+					LinkedHashMap<String,Object> r = (LinkedHashMap<String,Object>)ro;
+					for(String requirement: r.keySet()) {
+						String targetName = (String)r.get(requirement);
+						NodeTemplate targetNode = _findNodeTemplate(targetName);
+						NodeType targetType = (NodeType)targetNode.getTypeDefinition();
+						for(CapabilityTypeDef capability: targetType.getCapabilitiesObjects()) {
+//							if(((ArrayList<String>)hostedOnRel.get("valid_target_types")).contains(capability.getType())) {
+							if(capability.inheritsFrom((ArrayList<String>)hostedOnRel.get("valid_target_types"))) {
+								if(_attributeExistsInType(targetType)) {
+									return targetNode;
+								}
+								return _findHostContainingAttribute(targetName);
+							}
+						}
+					}
+				}
+			}
+		}
+		return null;
+	}
+	
+
+	private NodeTemplate _findNodeTemplate(String nodeTemplateName) {
+	    if(nodeTemplateName.equals(HOST)) {
+	        // Currently this is the only way to tell whether the function
+	        // is used within the outputs section of the TOSCA template.
+	        if(context instanceof ArrayList) {
+	            ThreadLocalsHolder.getCollector().appendException(
+	                "ValueError: \"get_attribute: [ HOST, ... ]\" is not allowed in \"outputs\" section of the TOSCA template");
+	            return null;
+	        }
+	        NodeTemplate nodeTpl = _findHostContainingAttribute(SELF);
+	        if(nodeTpl == null) {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "ValueError: \"get_attribute: [ HOST, ... ]\" was used in " +
+	                "node template \"%s\" but \"%s\" was not found in " +
+	                "the relationship chain",((NodeTemplate)context).getName(),HOSTED_ON));
+	            return null;
+	        }
+	        return nodeTpl;
+	    }
+	    if(nodeTemplateName.equals(TARGET)) {
+	    	if(!(((EntityTemplate)context).getTypeDefinition() instanceof RelationshipType)) {
+	            ThreadLocalsHolder.getCollector().appendException(
+	                "KeyError: \"TARGET\" keyword can only be used in context " +
+	                           " to \"Relationships\" target node");
+	            return null;
+	    	}
+	        return ((RelationshipTemplate)context).getTarget();
+	    }
+	    if(nodeTemplateName.equals(SOURCE)) {
+	    	if(!(((EntityTemplate)context).getTypeDefinition() instanceof RelationshipType)) {
+	            ThreadLocalsHolder.getCollector().appendException(
+	                "KeyError: \"SOURCE\" keyword can only be used in context " +
+	                           " to \"Relationships\" source node");
+	            return null;
+	    	}
+	        return ((RelationshipTemplate)context).getTarget();
+	    }
+	    String name;
+	    if(nodeTemplateName.equals(SELF) && !(context instanceof ArrayList)) {
+	    	name = ((NodeTemplate)context).getName();
+	    }
+	    else {
+	    	name = nodeTemplateName;
+	    }
+	    for(NodeTemplate nt: toscaTpl.getNodeTemplates()) {
+	        if(nt.getName().equals(name)) {
+	            return nt;
+	        }
+	    }
+	    ThreadLocalsHolder.getCollector().appendException(String.format(
+	        "KeyError: Node template \"%s\" was not found",nodeTemplateName));
+    	return null;
+    }
+	
+	public AttributeDef _findReqOrCapAttribute(String reqOrCap,String attrName) {
+
+		NodeTemplate nodeTpl = _findNodeTemplate((String)args.get(0));
+	    // Find attribute in node template's requirements
+		for(Object ro: nodeTpl.getRequirements()) {
+			if(ro != null && ro instanceof LinkedHashMap) {
+				LinkedHashMap<String,Object> r = (LinkedHashMap<String,Object>)ro;
+				for(String req: r.keySet()) {
+					String nodeName = (String)r.get(req);
+					if(req.equals(reqOrCap)) {
+						NodeTemplate nodeTemplate = _findNodeTemplate(nodeName);
+    	                return _getCapabilityAttribute(nodeTemplate,req,attrName);
+					}
+				}
+			}
+		}
+	    // If requirement was not found, look in node template's capabilities
+	    return _getCapabilityAttribute(nodeTpl,reqOrCap,attrName);
+	}
+
+	private AttributeDef _getCapabilityAttribute(NodeTemplate nodeTemplate,
+										  String capabilityName,
+										  String attrName) {
+	    // Gets a node template capability attribute
+	    LinkedHashMap<String,Capability> caps = nodeTemplate.getCapabilities();
+	    if(caps != null && caps.keySet().contains(capabilityName)) {
+	    	Capability cap = caps.get(capabilityName);
+	    	AttributeDef attribute = null;
+	    	LinkedHashMap<String,AttributeDef> attrs =
+	    			cap.getDefinition().getAttributesDef();
+	    	if(attrs != null && attrs.keySet().contains(attrName)) {
+	    		attribute = attrs.get(attrName);
+	    	}
+	        if(attribute == null) {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "KeyError: Attribute \"%s\" was not found in capability \"%s\" of node template \"%s\" referenced from node template \"%s\"",
+	                attrName,capabilityName,nodeTemplate.getName(),((NodeTemplate)context).getName()));
+	        }
+	        return attribute;
+	    }
+	    String msg = String.format(
+	    	"Requirement/Capability \"%s\" referenced from node template \"%s\" was not found in node template \"%s\"",
+	    	capabilityName,((NodeTemplate)context).getName(),nodeTemplate.getName());
+	    ThreadLocalsHolder.getCollector().appendException("KeyError: " + msg);
+		return null;									  
+	}
+
+	String getNodeTemplateName() {
+		return (String)args.get(0);
+	}
+
+	String getAttributeName() {
+		return (String)args.get(1);
+	}
+
+}
+
+/*python
+
+class GetAttribute(Function):
+"""Get an attribute value of an entity defined in the service template
+
+Node template attributes values are set in runtime and therefore its the
+responsibility of the Tosca engine to implement the evaluation of
+get_attribute functions.
+
+Arguments:
+
+* Node template name | HOST.
+* Attribute name.
+
+If the HOST keyword is passed as the node template name argument the
+function will search each node template along the HostedOn relationship
+chain until a node which contains the attribute is found.
+
+Examples:
+
+* { get_attribute: [ server, private_address ] }
+* { get_attribute: [ HOST, private_address ] }
+* { get_attribute: [ HOST, private_address, 0 ] }
+* { get_attribute: [ HOST, private_address, 0, some_prop] }
+"""
+
+def validate(self):
+    if len(self.args) < 2:
+        ExceptionCollector.appendException(
+            ValueError(_('Illegal arguments for function "{0}". Expected '
+                         'arguments: "node-template-name", "req-or-cap"'
+                         '(optional), "property name"'
+                         ).format(GET_ATTRIBUTE)))
+        return
+    elif len(self.args) == 2:
+        self._find_node_template_containing_attribute()
+    else:
+        node_tpl = self._find_node_template(self.args[0])
+        if node_tpl is None:
+            return
+        index = 2
+        attrs = node_tpl.type_definition.get_attributes_def()
+        found = [attrs[self.args[1]]] if self.args[1] in attrs else []
+        if found:
+            attr = found[0]
+        else:
+            index = 3
+            # then check the req or caps
+            attr = self._find_req_or_cap_attribute(self.args[1],
+                                                   self.args[2])
+
+        value_type = attr.schema['type']
+        if len(self.args) > index:
+            for elem in self.args[index:]:
+                if value_type == "list":
+                    if not isinstance(elem, int):
+                        ExceptionCollector.appendException(
+                            ValueError(_('Illegal arguments for function'
+                                         ' "{0}". "{1}" Expected positive'
+                                         ' integer argument'
+                                         ).format(GET_ATTRIBUTE, elem)))
+                    value_type = attr.schema['entry_schema']['type']
+                elif value_type == "map":
+                    value_type = attr.schema['entry_schema']['type']
+                elif value_type in Schema.PROPERTY_TYPES:
+                    ExceptionCollector.appendException(
+                        ValueError(_('Illegal arguments for function'
+                                     ' "{0}". Unexpected attribute/'
+                                     'index value "{1}"'
+                                     ).format(GET_ATTRIBUTE, elem)))
+                    return
+                else:  # It is a complex type
+                    data_type = DataType(value_type)
+                    props = data_type.get_all_properties()
+                    found = [props[elem]] if elem in props else []
+                    if found:
+                        prop = found[0]
+                        value_type = prop.schema['type']
+                    else:
+                        ExceptionCollector.appendException(
+                            KeyError(_('Illegal arguments for function'
+                                       ' "{0}". Attribute name "{1}" not'
+                                       ' found in "{2}"'
+                                       ).format(GET_ATTRIBUTE,
+                                                elem,
+                                                value_type)))
+
+def result(self):
+    return self
+
+def get_referenced_node_template(self):
+    """Gets the NodeTemplate instance the get_attribute function refers to.
+
+    If HOST keyword was used as the node template argument, the node
+    template which contains the attribute along the HostedOn relationship
+    chain will be returned.
+    """
+    return self._find_node_template_containing_attribute()
+
+# Attributes can be explicitly created as part of the type definition
+# or a property name can be implicitly used as an attribute name
+def _find_node_template_containing_attribute(self):
+    node_tpl = self._find_node_template(self.args[0])
+    if node_tpl and \
+            not self._attribute_exists_in_type(node_tpl.type_definition) \
+            and self.attribute_name not in node_tpl.get_properties():
+        ExceptionCollector.appendException(
+            KeyError(_('Attribute "%(att)s" was not found in node '
+                       'template "%(ntpl)s".') %
+                     {'att': self.attribute_name,
+                      'ntpl': node_tpl.name}))
+    return node_tpl
+
+def _attribute_exists_in_type(self, type_definition):
+    attrs_def = type_definition.get_attributes_def()
+    found = [attrs_def[self.attribute_name]] \
+        if self.attribute_name in attrs_def else []
+    return len(found) == 1
+
+def _find_host_containing_attribute(self, node_template_name=SELF):
+    node_template = self._find_node_template(node_template_name)
+    if node_template:
+        hosted_on_rel = EntityType.TOSCA_DEF[HOSTED_ON]
+        for r in node_template.requirements:
+            for requirement, target_name in r.items():
+                target_node = self._find_node_template(target_name)
+                target_type = target_node.type_definition
+                for capability in target_type.get_capabilities_objects():
+                    if capability.type in \
+                            hosted_on_rel['valid_target_types']:
+                        if self._attribute_exists_in_type(target_type):
+                            return target_node
+                        return self._find_host_containing_attribute(
+                            target_name)
+
+def _find_node_template(self, node_template_name):
+    if node_template_name == HOST:
+        # Currently this is the only way to tell whether the function
+        # is used within the outputs section of the TOSCA template.
+        if isinstance(self.context, list):
+            ExceptionCollector.appendException(
+                ValueError(_(
+                    '"get_attribute: [ HOST, ... ]" is not allowed in '
+                    '"outputs" section of the TOSCA template.')))
+            return
+        node_tpl = self._find_host_containing_attribute()
+        if not node_tpl:
+            ExceptionCollector.appendException(
+                ValueError(_(
+                    '"get_attribute: [ HOST, ... ]" was used in node '
+                    'template "{0}" but "{1}" was not found in '
+                    'the relationship chain.').format(self.context.name,
+                                                      HOSTED_ON)))
+            return
+        return node_tpl
+    if node_template_name == TARGET:
+        if not isinstance(self.context.type_definition, RelationshipType):
+            ExceptionCollector.appendException(
+                KeyError(_('"TARGET" keyword can only be used in context'
+                           ' to "Relationships" target node')))
+            return
+        return self.context.target
+    if node_template_name == SOURCE:
+        if not isinstance(self.context.type_definition, RelationshipType):
+            ExceptionCollector.appendException(
+                KeyError(_('"SOURCE" keyword can only be used in context'
+                           ' to "Relationships" source node')))
+            return
+        return self.context.source
+    name = self.context.name \
+        if node_template_name == SELF and \
+        not isinstance(self.context, list) \
+        else node_template_name
+    for node_template in self.tosca_tpl.nodetemplates:
+        if node_template.name == name:
+            return node_template
+    ExceptionCollector.appendException(
+        KeyError(_(
+            'Node template "{0}" was not found.'
+            ).format(node_template_name)))
+
+def _find_req_or_cap_attribute(self, req_or_cap, attr_name):
+    node_tpl = self._find_node_template(self.args[0])
+    # Find attribute in node template's requirements
+    for r in node_tpl.requirements:
+        for req, node_name in r.items():
+            if req == req_or_cap:
+                node_template = self._find_node_template(node_name)
+                return self._get_capability_attribute(
+                    node_template,
+                    req,
+                    attr_name)
+    # If requirement was not found, look in node template's capabilities
+    return self._get_capability_attribute(node_tpl,
+                                          req_or_cap,
+                                          attr_name)
+
+def _get_capability_attribute(self,
+                              node_template,
+                              capability_name,
+                              attr_name):
+    """Gets a node template capability attribute."""
+    caps = node_template.get_capabilities()
+    if caps and capability_name in caps.keys():
+        cap = caps[capability_name]
+        attribute = None
+        attrs = cap.definition.get_attributes_def()
+        if attrs and attr_name in attrs.keys():
+            attribute = attrs[attr_name]
+        if not attribute:
+            ExceptionCollector.appendException(
+                KeyError(_('Attribute "%(attr)s" was not found in '
+                           'capability "%(cap)s" of node template '
+                           '"%(ntpl1)s" referenced from node template '
+                           '"%(ntpl2)s".') % {'attr': attr_name,
+                                              'cap': capability_name,
+                                              'ntpl1': node_template.name,
+                                              'ntpl2': self.context.name}))
+        return attribute
+    msg = _('Requirement/Capability "{0}" referenced from node template '
+            '"{1}" was not found in node template "{2}".').format(
+                capability_name,
+                self.context.name,
+                node_template.name)
+    ExceptionCollector.appendException(KeyError(msg))
+
+@property
+def node_template_name(self):
+    return self.args[0]
+
+@property
+def attribute_name(self):
+    return self.args[1]
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetInput.java b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetInput.java
new file mode 100644
index 0000000..4332f70
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetInput.java
@@ -0,0 +1,110 @@
+package org.openecomp.sdc.toscaparser.api.functions;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.DataEntity;
+import org.openecomp.sdc.toscaparser.api.TopologyTemplate;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.parameters.Input;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class GetInput extends Function {
+	
+	public GetInput(TopologyTemplate toscaTpl,Object context,String name,ArrayList<Object> _args) {
+		super(toscaTpl,context,name,_args);
+		
+	}
+
+	@Override
+	void validate() {
+	    if(args.size() != 1) {
+	    	//PA - changed to WARNING from CRITICAL after talking to Renana, 22/05/2017
+	        ThreadLocalsHolder.getCollector().appendWarning(String.format(
+	            "ValueError: Expected one argument for function \"get_input\" but received \"%s\"",
+	            args.toString()));
+	    }
+	    boolean bFound = false;
+	    for(Input inp: toscaTpl.getInputs()) {
+	    	if(inp.getName().equals(args.get(0))) {
+	    		bFound = true;
+	    		break;
+	    	}
+	    }
+	    if(!bFound) {
+	        ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "UnknownInputError: Unknown input \"%s\"",args.get(0)));
+	    }
+	}
+
+	public 	Object result() {
+		if(toscaTpl.getParsedParams() != null && 
+				toscaTpl.getParsedParams().get(getInputName()) != null) {
+			LinkedHashMap<String,Object> ttinp = (LinkedHashMap<String,Object>)toscaTpl.getTpl().get("inputs");
+			LinkedHashMap<String,Object> ttinpinp = (LinkedHashMap<String,Object>)ttinp.get(getInputName());
+			String type = (String)ttinpinp.get("type");
+			
+			return DataEntity.validateDatatype(
+					type, toscaTpl.getParsedParams().get(getInputName()),null,null,null);
+		}
+		
+		Input inputDef = null;
+		for(Input inpDef: toscaTpl.getInputs()) {
+			if(getInputName().equals(inpDef.getName())) {
+				inputDef = inpDef;
+				break;
+			}
+		}
+		if(inputDef != null) {
+			return inputDef.getDefault();
+		}
+		return null;
+	}
+	
+	public String getInputName() {
+		return (String)args.get(0);
+	}
+
+}
+
+/*python
+
+class GetInput(Function):
+"""Get a property value declared within the input of the service template.
+
+Arguments:
+
+* Input name.
+
+Example:
+
+* get_input: port
+"""
+
+def validate(self):
+    if len(self.args) != 1:
+        ExceptionCollector.appendException(
+            ValueError(_(
+                'Expected one argument for function "get_input" but '
+                'received "%s".') % self.args))
+    inputs = [input.name for input in self.tosca_tpl.inputs]
+    if self.args[0] not in inputs:
+        ExceptionCollector.appendException(
+            UnknownInputError(input_name=self.args[0]))
+
+def result(self):
+    if self.tosca_tpl.parsed_params and \
+       self.input_name in self.tosca_tpl.parsed_params:
+        return DataEntity.validate_datatype(
+            self.tosca_tpl.tpl['inputs'][self.input_name]['type'],
+            self.tosca_tpl.parsed_params[self.input_name])
+
+    input = [input_def for input_def in self.tosca_tpl.inputs
+             if self.input_name == input_def.name][0]
+    return input.default
+
+@property
+def input_name(self):
+    return self.args[0]
+
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetOperationOutput.java b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetOperationOutput.java
new file mode 100644
index 0000000..22f2cd7
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetOperationOutput.java
@@ -0,0 +1,225 @@
+package org.openecomp.sdc.toscaparser.api.functions;
+
+import java.util.ArrayList;
+
+import org.openecomp.sdc.toscaparser.api.*;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.InterfacesDef;
+import org.openecomp.sdc.toscaparser.api.elements.RelationshipType;
+import org.openecomp.sdc.toscaparser.api.elements.StatefulEntityType;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class GetOperationOutput extends Function {
+
+	public GetOperationOutput(TopologyTemplate ttpl,Object context,String name,ArrayList<Object> args) {
+		super(ttpl,context,name,args);
+	}
+
+	@Override
+	public void validate() {
+	    if(args.size() == 4) {
+	        _findNodeTemplate((String)args.get(0));
+	        String interfaceName = _findInterfaceName((String)args.get(1));
+	        _findOperationName(interfaceName,(String)args.get(2));
+	    }
+	    else {
+	        ThreadLocalsHolder.getCollector().appendException(
+	            "ValueError: Illegal arguments for function \"get_operation_output\". " +
+	            "Expected arguments: \"template_name\",\"interface_name\"," +
+	            "\"operation_name\",\"output_variable_name\"");
+	    }
+	}
+	
+	private String _findInterfaceName(String _interfaceName) {
+		boolean bFound = false;
+		for(String sect: InterfacesDef.SECTIONS) {
+			if(sect.equals(_interfaceName)) {
+				bFound = true;
+				break;
+			}
+		}
+	    if(bFound) {
+	        return _interfaceName;
+	    }
+	    else {
+	        ThreadLocalsHolder.getCollector().appendException(String.format(
+	        	"ValueError: invalid interface name \"%s\" in \"get_operation_output\"",
+	        	_interfaceName));
+	        return null;
+	    }
+	}
+
+	private String _findOperationName(String interfaceName,String operationName) {
+		
+	    if(interfaceName.equals("Configure") ||
+	       interfaceName.equals("tosca.interfaces.node.relationship.Configure")) {
+			boolean bFound = false;
+			for(String sect: StatefulEntityType.interfacesRelationshipConfigureOperations) {
+				if(sect.equals(operationName)) {
+					bFound = true;
+					break;
+				}
+			}
+		    if(bFound) {
+	 	        return operationName;
+		    }
+ 	        else {
+ 	            ThreadLocalsHolder.getCollector().appendException(String.format(
+ 	            	"ValueError: Invalid operation of Configure interface \"%s\" in \"get_operation_output\"",
+ 	            	operationName));
+ 	            return null;
+ 	        }
+	    }
+	    if(interfaceName.equals("Standard") ||
+ 	       interfaceName.equals("tosca.interfaces.node.lifecycle.Standard")) {
+ 			boolean bFound = false;
+ 			for(String sect: StatefulEntityType.interfacesNodeLifecycleOperations) {
+ 				if(sect.equals(operationName)) {
+ 					bFound = true;
+ 					break;
+ 				}
+ 			}
+ 		    if(bFound) {
+ 	 	        return operationName;
+ 		    }
+  	        else {
+  	            ThreadLocalsHolder.getCollector().appendException(String.format(
+ 	            	"ValueError: Invalid operation of Configure interface \"%s\" in \"get_operation_output\"",
+ 	            	operationName));
+ 	            return null;
+ 	        }
+	    }
+	    else {
+	        ThreadLocalsHolder.getCollector().appendException(String.format(
+	            	"ValueError: Invalid interface name \"%s\" in \"get_operation_output\"",
+ 	            	interfaceName));
+	        return null;
+	    }
+	}
+	
+	private NodeTemplate _findNodeTemplate(String nodeTemplateName) {
+	    if(nodeTemplateName.equals(TARGET)) {
+	    	if(!(((EntityTemplate)context).getTypeDefinition() instanceof RelationshipType)) {
+	            ThreadLocalsHolder.getCollector().appendException(
+	                "KeyError: \"TARGET\" keyword can only be used in context " +
+	                           " to \"Relationships\" target node");
+	            return null;
+	    	}
+	        return ((RelationshipTemplate)context).getTarget();
+	    }
+	    if(nodeTemplateName.equals(SOURCE)) {
+	    	if(!(((EntityTemplate)context).getTypeDefinition() instanceof RelationshipType)) {
+	            ThreadLocalsHolder.getCollector().appendException(
+	                "KeyError: \"SOURCE\" keyword can only be used in context " +
+	                           " to \"Relationships\" source node");
+	            return null;
+	    	}
+	        return ((RelationshipTemplate)context).getTarget();
+	    }
+	    String name;
+	    if(nodeTemplateName.equals(SELF) && !(context instanceof ArrayList)) {
+	    	name = ((NodeTemplate)context).getName();
+	    }
+	    else {
+	    	name = nodeTemplateName;
+	    }
+	    for(NodeTemplate nt: toscaTpl.getNodeTemplates()) {
+	        if(nodeTemplateName.equals(name)) {
+	            return nt;
+	        }
+	    }
+	    ThreadLocalsHolder.getCollector().appendException(String.format(
+	        "KeyError: Node template \"%s\" was not found",nodeTemplateName));
+    	return null;
+    }
+
+	@Override
+	public Object result() {
+		return this;
+	}
+
+}
+
+/*python 
+
+class GetOperationOutput(Function):
+def validate(self):
+    if len(self.args) == 4:
+        self._find_node_template(self.args[0])
+        interface_name = self._find_interface_name(self.args[1])
+        self._find_operation_name(interface_name, self.args[2])
+    else:
+        ExceptionCollector.appendException(
+            ValueError(_('Illegal arguments for function "{0}". Expected '
+                         'arguments: "template_name","interface_name",'
+                         '"operation_name","output_variable_name"'
+                         ).format(GET_OPERATION_OUTPUT)))
+        return
+
+def _find_interface_name(self, interface_name):
+    if interface_name in toscaparser.elements.interfaces.SECTIONS:
+        return interface_name
+    else:
+        ExceptionCollector.appendException(
+            ValueError(_('Enter a valid interface name'
+                         ).format(GET_OPERATION_OUTPUT)))
+        return
+
+def _find_operation_name(self, interface_name, operation_name):
+    if(interface_name == 'Configure' or
+       interface_name == 'tosca.interfaces.node.relationship.Configure'):
+        if(operation_name in
+           StatefulEntityType.
+           interfaces_relationship_configure_operations):
+            return operation_name
+        else:
+            ExceptionCollector.appendException(
+                ValueError(_('Enter an operation of Configure interface'
+                             ).format(GET_OPERATION_OUTPUT)))
+            return
+    elif(interface_name == 'Standard' or
+         interface_name == 'tosca.interfaces.node.lifecycle.Standard'):
+        if(operation_name in
+           StatefulEntityType.interfaces_node_lifecycle_operations):
+            return operation_name
+        else:
+            ExceptionCollector.appendException(
+                ValueError(_('Enter an operation of Standard interface'
+                             ).format(GET_OPERATION_OUTPUT)))
+            return
+    else:
+        ExceptionCollector.appendException(
+            ValueError(_('Enter a valid operation name'
+                         ).format(GET_OPERATION_OUTPUT)))
+        return
+
+def _find_node_template(self, node_template_name):
+    if node_template_name == TARGET:
+        if not isinstance(self.context.type_definition, RelationshipType):
+            ExceptionCollector.appendException(
+                KeyError(_('"TARGET" keyword can only be used in context'
+                           ' to "Relationships" target node')))
+            return
+        return self.context.target
+    if node_template_name == SOURCE:
+        if not isinstance(self.context.type_definition, RelationshipType):
+            ExceptionCollector.appendException(
+                KeyError(_('"SOURCE" keyword can only be used in context'
+                           ' to "Relationships" source node')))
+            return
+        return self.context.source
+    name = self.context.name \
+        if node_template_name == SELF and \
+        not isinstance(self.context, list) \
+        else node_template_name
+    for node_template in self.tosca_tpl.nodetemplates:
+        if node_template.name == name:
+            return node_template
+    ExceptionCollector.appendException(
+        KeyError(_(
+            'Node template "{0}" was not found.'
+            ).format(node_template_name)))
+
+def result(self):
+    return self
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetProperty.java b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetProperty.java
new file mode 100644
index 0000000..3550542
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/GetProperty.java
@@ -0,0 +1,636 @@
+package org.openecomp.sdc.toscaparser.api.functions;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.*;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.CapabilityTypeDef;
+import org.openecomp.sdc.toscaparser.api.elements.EntityType;
+import org.openecomp.sdc.toscaparser.api.elements.NodeType;
+import org.openecomp.sdc.toscaparser.api.elements.PropertyDef;
+import org.openecomp.sdc.toscaparser.api.elements.RelationshipType;
+import org.openecomp.sdc.toscaparser.api.elements.StatefulEntityType;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class GetProperty extends Function {
+	// Get a property value of an entity defined in the same service template
+
+	// Arguments:
+
+	// * Node template name | SELF | HOST | SOURCE | TARGET.
+	// * Requirement or capability name (optional).
+	// * Property name.
+
+	// If requirement or capability name is specified, the behavior is as follows:
+	// The req or cap name is first looked up in the specified node template's
+	// requirements.
+	// If found, it would search for a matching capability
+	// of an other node template and get its property as specified in function
+	// arguments.
+	// Otherwise, the req or cap name would be looked up in the specified
+	// node template's capabilities and if found, it would return  the property of
+	// the capability as specified in function arguments.
+
+	// Examples:
+
+	// * { get_property: [ mysql_server, port ] }
+	// * { get_property: [ SELF, db_port ] }
+	// * { get_property: [ SELF, database_endpoint, port ] }
+	// * { get_property: [ SELF, database_endpoint, port, 1 ] }
+
+	
+	public GetProperty(TopologyTemplate ttpl,Object context,String name,ArrayList<Object> args) {
+		super(ttpl,context,name,args);
+	}
+	
+	@Override
+	void validate() { 
+		if(args.size() < 2) {
+	        ThreadLocalsHolder.getCollector().appendException(
+		        "ValueError: Illegal arguments for function \"get_property\". Expected arguments: \"node-template-name\", \"req-or-cap\" (optional), \"property name.\"");
+		        return;
+		}
+	    if(args.size() == 2) {
+	        Property foundProp = _findProperty((String)args.get(1));
+	        if(foundProp == null) {
+	            return;
+	        }
+	        Object prop = foundProp.getValue();
+	        if(prop instanceof Function) {
+	            Function.getFunction(toscaTpl,context, prop);
+	        }
+	    }
+	    else if(args.size() >= 3) {
+	        // do not use _find_property to avoid raise KeyError
+	        // if the prop is not found
+	        // First check if there is property with this name
+	        NodeTemplate nodeTpl = _findNodeTemplate((String)args.get(0));
+	        LinkedHashMap<String,Property> props;
+	        if(nodeTpl != null) {
+	        	props = nodeTpl.getProperties();
+	        }
+	        else {
+	        	props = new LinkedHashMap<>();
+	        }
+	        int index = 2;
+	        Object propertyValue;
+	        if(props.get(args.get(1)) != null) {
+	        	propertyValue = ((Property)props.get(args.get(1))).getValue();
+	        }
+	        else {
+	        	index = 3;
+	            // then check the req or caps
+	            propertyValue = _findReqOrCapProperty((String)args.get(1),(String)args.get(2));
+	        }
+	        	
+	        if(args.size() > index) {
+	        	for(Object elem: args.subList(index,args.size()-1)) {
+	        		if(propertyValue instanceof ArrayList) {
+	                   int intElem = (int)elem;
+	                    propertyValue = _getIndexValue(propertyValue,intElem);
+	        		}
+	        		else {
+	                    propertyValue = _getAttributeValue(propertyValue,(String)elem);
+	        		}
+	        	}
+	        }
+	    }
+	}
+	
+	@SuppressWarnings("unchecked")
+	private Object _findReqOrCapProperty(String reqOrCap,String propertyName) {
+        NodeTemplate nodeTpl = _findNodeTemplate((String)args.get(0));
+        if(nodeTpl == null) {
+        	return null;
+        }
+	    // look for property in node template's requirements
+	    for(Object r: nodeTpl.getRequirements()) {
+	    	if(r instanceof LinkedHashMap) {
+	    		LinkedHashMap<String,Object> rlist = (LinkedHashMap<String,Object>)r;
+	    		for(String req: rlist.keySet()) {
+	    			String nodeName = (String)rlist.get(req);
+	    			if(req.equals(reqOrCap)) {
+	    				NodeTemplate nodeTemplate = _findNodeTemplate(nodeName);
+		    	        return _getCapabilityProperty(nodeTemplate,req,propertyName,true);
+	    			}
+	    		}
+	    	}
+	    }	    	
+		// If requirement was not found, look in node template's capabilities
+		return _getCapabilityProperty(nodeTpl,reqOrCap,propertyName,true);
+	}
+	
+	private Object _getCapabilityProperty(NodeTemplate nodeTemplate,
+											String capabilityName,
+											String propertyName,
+											boolean throwErrors) {
+		
+	    // Gets a node template capability property
+		Object property = null;
+		LinkedHashMap<String,Capability> caps = nodeTemplate.getCapabilities();
+		if(caps != null && caps.get(capabilityName) != null) {
+			Capability cap = caps.get(capabilityName);
+			LinkedHashMap<String,Property> props = cap.getProperties();
+	        if(props != null && props.get(propertyName) != null) {
+	            property = ((Property)props.get(propertyName)).getValue();
+	        }
+	        if(property == null && throwErrors) {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "KeyError: Property \"%s\" was not found in capability \"%s\" of node template \"%s\" referenced from node template \"%s\"",
+	                propertyName,capabilityName,nodeTemplate.getName(),((NodeTemplate)context).getName()));
+	        }
+    		return property;
+		}
+		if(throwErrors) {
+		    ThreadLocalsHolder.getCollector().appendException(String.format(
+		    	"KeyError: Requirement/Capability \"%s\" referenced from node template \"%s\" was not found in node template \"%s\"",
+		    	capabilityName,((NodeTemplate)context).getName(),nodeTemplate.getName()));
+		}
+		
+		return null;
+	}
+	
+	private Property _findProperty(String propertyName) {
+        NodeTemplate nodeTpl = _findNodeTemplate((String)args.get(0));
+        if(nodeTpl == null) {
+        	return null;
+        }
+        LinkedHashMap<String,Property> props = nodeTpl.getProperties();
+		Property found = props.get(propertyName);
+		if(found == null) {
+	        ThreadLocalsHolder.getCollector().appendException(String.format(
+		        "KeyError: Property \"%s\" was not found in node template \"%s\"",
+		        propertyName,nodeTpl.getName()));
+		}
+		return found;
+	}
+	
+	private NodeTemplate _findNodeTemplate(String nodeTemplateName) {
+		if(nodeTemplateName.equals(SELF)) {
+			return (NodeTemplate)context;
+		}
+	    // enable the HOST value in the function
+	    if(nodeTemplateName.equals(HOST)) {
+	        NodeTemplate node = _findHostContainingProperty(null);
+	        if(node == null) {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+		            "KeyError: Property \"%s\" was not found in capability \"%s\" of node template \"%s\" referenced from node template \"%s\"",
+		            (String)args.get(2),(String)args.get(1),((NodeTemplate)context).getName()));
+	            return null;
+	        }
+	        return node;
+	    }
+	    if(nodeTemplateName.equals(TARGET)) {
+	    	if(!(((RelationshipTemplate)context).getTypeDefinition() instanceof RelationshipType)) {
+	            ThreadLocalsHolder.getCollector().appendException(
+		            "KeyError: \"TARGET\" keyword can only be used in context to \"Relationships\" target node");
+	            return null;
+	    	}
+	    	return ((RelationshipTemplate)context).getTarget();
+	    }
+	    if(nodeTemplateName.equals(SOURCE)) {
+	    	if(!(((RelationshipTemplate)context).getTypeDefinition() instanceof RelationshipType)) {
+	            ThreadLocalsHolder.getCollector().appendException(
+		            "KeyError: \"SOURCE\" keyword can only be used in context to \"Relationships\" target node");
+	            return null;
+	    	}
+	    	return ((RelationshipTemplate)context).getSource();
+	    }		
+	    if(toscaTpl.getNodeTemplates() == null) {
+	        return null;
+	    }
+	    for(NodeTemplate nodeTemplate: toscaTpl.getNodeTemplates()) {
+	        if(nodeTemplate.getName().equals(nodeTemplateName)) {
+	            return nodeTemplate;
+	        }
+	    }
+	    ThreadLocalsHolder.getCollector().appendException(String.format(
+	        "KeyError: Node template \"%s\" was not found. Referenced from Node Template \"%s\"", 
+	        nodeTemplateName,((NodeTemplate)context).getName()));
+	    
+	    return null;
+	}
+
+	@SuppressWarnings("rawtypes")
+	private Object _getIndexValue(Object value,int index) {
+		if(value instanceof ArrayList) {
+			if(index < ((ArrayList)value).size()) {
+				return ((ArrayList)value).get(index);
+			}
+			else {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+		            "KeyError: Property \"%s\" found in capability \"%s\" referenced from node template \"%s\" must have an element with index %d",
+		            args.get(2),args.get(1),((NodeTemplate)context).getName(),index));
+
+			}
+		}
+		else {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+		            "KeyError: Property \"%s\" found in capability \"%s\" referenced from node template \"%s\" must be a list",
+		            args.get(2),args.get(1),((NodeTemplate)context).getName()));
+		}
+		return null;
+	}
+
+	@SuppressWarnings("unchecked")
+	private Object _getAttributeValue(Object value,String attribute) {
+	    if(value instanceof LinkedHashMap) {
+	    	Object ov = ((LinkedHashMap<String,Object>)value).get(attribute);
+	    	if(ov != null) {
+	            return ov;
+	    	}
+	        else {
+	            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "KeyError: Property \"%s\" found in capability \"%s\" referenced from node template \"%s\" must have an attribute named \"%s\"",
+		            args.get(2),args.get(1),((NodeTemplate)context).getName(),attribute));
+	        }
+	    }
+	    else {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "KeyError: Property \"%s\" found in capability \"%s\" referenced from node template \"%s\" must be a dict",
+		            args.get(2),args.get(1),((NodeTemplate)context).getName()));
+	    }
+	    return null;
+	}
+
+	// Add this functions similar to get_attribute case
+	private NodeTemplate _findHostContainingProperty(String nodeTemplateName) {
+		if(nodeTemplateName == null) {
+			nodeTemplateName = SELF;
+		}
+	    NodeTemplate nodeTemplate = _findNodeTemplate(nodeTemplateName);
+	    LinkedHashMap<String,Object> hostedOnRel = (LinkedHashMap<String,Object>)
+	    												EntityType.TOSCA_DEF.get(HOSTED_ON);
+	    for(Object r: nodeTemplate.getRequirements()) {
+	    	if(r instanceof LinkedHashMap) {
+	    		LinkedHashMap<String,Object> rlist = (LinkedHashMap<String,Object>)r;
+	    		for(String requirement: rlist.keySet()) {
+	    			String targetName = (String)rlist.get(requirement);
+    				NodeTemplate targetNode = _findNodeTemplate(targetName);
+    				NodeType targetType = (NodeType)targetNode.getTypeDefinition();
+	    	        for(CapabilityTypeDef capDef: targetType.getCapabilitiesObjects()) {
+	    	        	if(capDef.inheritsFrom((ArrayList<String>)hostedOnRel.get("valid_target_types"))) {
+	    	        		if(_propertyExistsInType(targetType)) {
+	    	        			return targetNode;
+	    	        		}
+	                        // If requirement was not found, look in node
+	                        // template's capabilities
+	                        if(args.size() > 2 && 
+	                        	_getCapabilityProperty(targetNode,(String)args.get(1),(String)args.get(2),false) != null) {
+	    	        			return targetNode;
+	    	        		}
+
+	    	        		return _findHostContainingProperty(targetName);
+	    	        	}
+	    	        }
+	    		}
+	    	}
+	    }
+	    return null;
+	}
+	
+	private boolean _propertyExistsInType(StatefulEntityType typeDefinition) {
+        LinkedHashMap<String,PropertyDef> propsDef = typeDefinition.getPropertiesDef();
+        return propsDef.keySet().contains((String)args.get(1)); 
+	}
+
+	@Override
+	public Object result() {
+        Object propertyValue;
+		if(args.size() >= 3) {
+	        // First check if there is property with this name
+	        NodeTemplate nodeTpl = _findNodeTemplate((String)args.get(0));
+	        LinkedHashMap<String,Property> props;
+	        if(nodeTpl != null) {
+	        	props = nodeTpl.getProperties();
+	        }
+	        else {
+	        	props = new LinkedHashMap<>();
+	        }
+	        int index = 2;
+	        if(props.get(args.get(1)) != null) {
+	        	propertyValue = ((Property)props.get(args.get(1))).getValue();
+	        }
+	        else {
+	        	index = 3;
+	            // then check the req or caps
+	            propertyValue = _findReqOrCapProperty((String)args.get(1),(String)args.get(2));
+	        }
+	        	
+	        if(args.size() > index) {
+	        	for(Object elem: args.subList(index,args.size()-1)) {
+	        		if(propertyValue instanceof ArrayList) {
+	                   int intElem = (int)elem;
+	                    propertyValue = _getIndexValue(propertyValue,intElem);
+	        		}
+	        		else {
+	                    propertyValue = _getAttributeValue(propertyValue,(String)elem);
+	        		}
+	        	}
+	        }
+		}
+		else {
+			propertyValue = _findProperty((String)args.get(1)).getValue();
+		}
+        if(propertyValue instanceof Function) {
+            return ((Function)propertyValue).result();
+        }
+        return Function.getFunction(toscaTpl,context,propertyValue);
+	}
+
+	public String getNodeTemplateName() {
+		return (String)args.get(0);
+	}
+
+	public String getPropertyName() {
+		if(args.size() > 2) {
+			return (String)args.get(2);
+		}
+		return (String)args.get(1);
+	}
+
+	public String getReqorCap() {
+		if(args.size() > 2) {
+			return (String)args.get(1);
+		}
+		return null;
+	}
+	
+}
+
+/*python
+
+class GetProperty(Function):
+"""Get a property value of an entity defined in the same service template.
+
+Arguments:
+
+* Node template name | SELF | HOST | SOURCE | TARGET.
+* Requirement or capability name (optional).
+* Property name.
+
+If requirement or capability name is specified, the behavior is as follows:
+The req or cap name is first looked up in the specified node template's
+requirements.
+If found, it would search for a matching capability
+of an other node template and get its property as specified in function
+arguments.
+Otherwise, the req or cap name would be looked up in the specified
+node template's capabilities and if found, it would return  the property of
+the capability as specified in function arguments.
+
+Examples:
+
+* { get_property: [ mysql_server, port ] }
+* { get_property: [ SELF, db_port ] }
+* { get_property: [ SELF, database_endpoint, port ] }
+* { get_property: [ SELF, database_endpoint, port, 1 ] }
+"""
+
+def validate(self):
+    if len(self.args) < 2:
+        ExceptionCollector.appendException(
+            ValueError(_(
+                'Expected arguments: "node-template-name", "req-or-cap" '
+                '(optional), "property name".')))
+        return
+    if len(self.args) == 2:
+        found_prop = self._find_property(self.args[1])
+        if not found_prop:
+            return
+        prop = found_prop.value
+        if not isinstance(prop, Function):
+            get_function(self.tosca_tpl, self.context, prop)
+    elif len(self.args) >= 3:
+        # do not use _find_property to avoid raise KeyError
+        # if the prop is not found
+        # First check if there is property with this name
+        node_tpl = self._find_node_template(self.args[0])
+        props = node_tpl.get_properties() if node_tpl else []
+        index = 2
+        found = [props[self.args[1]]] if self.args[1] in props else []
+        if found:
+            property_value = found[0].value
+        else:
+            index = 3
+            # then check the req or caps
+            property_value = self._find_req_or_cap_property(self.args[1],
+                                                            self.args[2])
+        if len(self.args) > index:
+            for elem in self.args[index:]:
+                if isinstance(property_value, list):
+                    int_elem = int(elem)
+                    property_value = self._get_index_value(property_value,
+                                                           int_elem)
+                else:
+                    property_value = self._get_attribute_value(
+                        property_value,
+                        elem)
+
+def _find_req_or_cap_property(self, req_or_cap, property_name):
+    node_tpl = self._find_node_template(self.args[0])
+    # Find property in node template's requirements
+    for r in node_tpl.requirements:
+        for req, node_name in r.items():
+            if req == req_or_cap:
+                node_template = self._find_node_template(node_name)
+                return self._get_capability_property(
+                    node_template,
+                    req,
+                    property_name)
+    # If requirement was not found, look in node template's capabilities
+    return self._get_capability_property(node_tpl,
+                                         req_or_cap,
+                                         property_name)
+
+def _get_capability_property(self,
+                             node_template,
+                             capability_name,
+                             property_name):
+    """Gets a node template capability property."""
+    caps = node_template.get_capabilities()
+    if caps and capability_name in caps.keys():
+        cap = caps[capability_name]
+        property = None
+        props = cap.get_properties()
+        if props and property_name in props.keys():
+            property = props[property_name].value
+        if not property:
+            ExceptionCollector.appendException(
+                KeyError(_('Property "%(prop)s" was not found in '
+                           'capability "%(cap)s" of node template '
+                           '"%(ntpl1)s" referenced from node template '
+                           '"%(ntpl2)s".') % {'prop': property_name,
+                                              'cap': capability_name,
+                                              'ntpl1': node_template.name,
+                                              'ntpl2': self.context.name}))
+        return property
+    msg = _('Requirement/Capability "{0}" referenced from node template '
+            '"{1}" was not found in node template "{2}".').format(
+                capability_name,
+                self.context.name,
+                node_template.name)
+    ExceptionCollector.appendException(KeyError(msg))
+
+def _find_property(self, property_name):
+    node_tpl = self._find_node_template(self.args[0])
+    if not node_tpl:
+        return
+    props = node_tpl.get_properties()
+    found = [props[property_name]] if property_name in props else []
+    if len(found) == 0:
+        ExceptionCollector.appendException(
+            KeyError(_('Property "%(prop)s" was not found in node '
+                       'template "%(ntpl)s".') %
+                     {'prop': property_name,
+                      'ntpl': node_tpl.name}))
+        return None
+    return found[0]
+
+def _find_node_template(self, node_template_name):
+    if node_template_name == SELF:
+        return self.context
+    # enable the HOST value in the function
+    if node_template_name == HOST:
+        return self._find_host_containing_property()
+    if node_template_name == TARGET:
+        if not isinstance(self.context.type_definition, RelationshipType):
+            ExceptionCollector.appendException(
+                KeyError(_('"TARGET" keyword can only be used in context'
+                           ' to "Relationships" target node')))
+            return
+        return self.context.target
+    if node_template_name == SOURCE:
+        if not isinstance(self.context.type_definition, RelationshipType):
+            ExceptionCollector.appendException(
+                KeyError(_('"SOURCE" keyword can only be used in context'
+                           ' to "Relationships" source node')))
+            return
+        return self.context.source
+    if not hasattr(self.tosca_tpl, 'nodetemplates'):
+        return
+    for node_template in self.tosca_tpl.nodetemplates:
+        if node_template.name == node_template_name:
+            return node_template
+    ExceptionCollector.appendException(
+        KeyError(_(
+            'Node template "{0}" was not found.'
+            ).format(node_template_name)))
+
+def _get_index_value(self, value, index):
+    if isinstance(value, list):
+        if index < len(value):
+            return value[index]
+        else:
+            ExceptionCollector.appendException(
+                KeyError(_(
+                    "Property '{0}' found in capability '{1}'"
+                    " referenced from node template {2}"
+                    " must have an element with index {3}.").
+                    format(self.args[2],
+                           self.args[1],
+                           self.context.name,
+                           index)))
+    else:
+        ExceptionCollector.appendException(
+            KeyError(_(
+                "Property '{0}' found in capability '{1}'"
+                " referenced from node template {2}"
+                " must be a list.").format(self.args[2],
+                                           self.args[1],
+                                           self.context.name)))
+
+def _get_attribute_value(self, value, attibute):
+    if isinstance(value, dict):
+        if attibute in value:
+            return value[attibute]
+        else:
+            ExceptionCollector.appendException(
+                KeyError(_(
+                    "Property '{0}' found in capability '{1}'"
+                    " referenced from node template {2}"
+                    " must have an attribute named {3}.").
+                    format(self.args[2],
+                           self.args[1],
+                           self.context.name,
+                           attibute)))
+    else:
+        ExceptionCollector.appendException(
+            KeyError(_(
+                "Property '{0}' found in capability '{1}'"
+                " referenced from node template {2}"
+                " must be a dict.").format(self.args[2],
+                                           self.args[1],
+                                           self.context.name)))
+
+# Add this functions similar to get_attribute case
+def _find_host_containing_property(self, node_template_name=SELF):
+    node_template = self._find_node_template(node_template_name)
+    hosted_on_rel = EntityType.TOSCA_DEF[HOSTED_ON]
+    for r in node_template.requirements:
+        for requirement, target_name in r.items():
+            target_node = self._find_node_template(target_name)
+            target_type = target_node.type_definition
+            for capability in target_type.get_capabilities_objects():
+                if capability.type in hosted_on_rel['valid_target_types']:
+                    if self._property_exists_in_type(target_type):
+                        return target_node
+                    return self._find_host_containing_property(
+                        target_name)
+    return None
+
+def _property_exists_in_type(self, type_definition):
+    props_def = type_definition.get_properties_def()
+    found = [props_def[self.args[1]]] \
+        if self.args[1] in props_def else []
+    return len(found) == 1
+
+def result(self):
+    if len(self.args) >= 3:
+        # First check if there is property with this name
+        node_tpl = self._find_node_template(self.args[0])
+        props = node_tpl.get_properties() if node_tpl else []
+        index = 2
+        found = [props[self.args[1]]] if self.args[1] in props else []
+        if found:
+            property_value = found[0].value
+        else:
+            index = 3
+            # then check the req or caps
+            property_value = self._find_req_or_cap_property(self.args[1],
+                                                            self.args[2])
+        if len(self.args) > index:
+            for elem in self.args[index:]:
+                if isinstance(property_value, list):
+                    int_elem = int(elem)
+                    property_value = self._get_index_value(property_value,
+                                                           int_elem)
+                else:
+                    property_value = self._get_attribute_value(
+                        property_value,
+                        elem)
+    else:
+        property_value = self._find_property(self.args[1]).value
+    if isinstance(property_value, Function):
+        return property_value.result()
+    return get_function(self.tosca_tpl,
+                        self.context,
+                        property_value)
+
+@property
+def node_template_name(self):
+    return self.args[0]
+
+@property
+def property_name(self):
+    if len(self.args) > 2:
+        return self.args[2]
+    return self.args[1]
+
+@property
+def req_or_cap(self):
+    if len(self.args) > 2:
+        return self.args[1]
+    return None
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/functions/Token.java b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/Token.java
new file mode 100644
index 0000000..4438908
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/functions/Token.java
@@ -0,0 +1,112 @@
+package org.openecomp.sdc.toscaparser.api.functions;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.NodeTemplate;
+import org.openecomp.sdc.toscaparser.api.TopologyTemplate;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class Token extends Function {
+    // Validate the function and provide an instance of the function
+
+    //The token function is used within a TOSCA service template on a string to
+    //parse out (tokenize) substrings separated by one or more token characters
+    //within a larger string.
+
+    //Arguments:
+
+    //* The composite string that contains one or more substrings separated by
+    //  token characters.
+    //* The string that contains one or more token characters that separate
+    //  substrings within the composite string.
+    //* The integer indicates the index of the substring to return from the
+    //  composite string.  Note that the first substring is denoted by using
+    //  the '0' (zero) integer value.
+
+    //Example:
+
+   // [ get_attribute: [ my_server, data_endpoint, ip_address ], ':', 1 ]
+
+
+	public Token(TopologyTemplate ttpl,Object context,String name,ArrayList<Object> args) {
+		super(ttpl,context,name,args);
+	}
+	
+	@Override
+	public Object result() {
+		return this;
+	}
+
+	@Override
+	void validate() {
+        if(args.size() < 3) {
+            ThreadLocalsHolder.getCollector().appendException(
+                "ValueError: Invalid arguments for function \"token\". " +
+                "Expected at least three arguments");
+        }
+        else {
+            if(!(args.get(1) instanceof String) || 
+               ((String)args.get(1)).length() != 1) {
+                ThreadLocalsHolder.getCollector().appendException(
+                    "ValueError: Invalid arguments for function \"token\". " +
+                    "Expected single char value as second argument");
+            }
+            if(!(args.get(2) instanceof Integer)) {
+                ThreadLocalsHolder.getCollector().appendException(
+                    "ValueError: Invalid arguments for function \"token\"" +
+                    "Expected integer value as third argument");
+        	}
+		}
+	}
+
+}
+
+/*python
+
+class Token(Function):
+"""Validate the function and provide an instance of the function
+
+The token function is used within a TOSCA service template on a string to
+parse out (tokenize) substrings separated by one or more token characters
+within a larger string.
+
+
+Arguments:
+
+* The composite string that contains one or more substrings separated by
+  token characters.
+* The string that contains one or more token characters that separate
+  substrings within the composite string.
+* The integer indicates the index of the substring to return from the
+  composite string.  Note that the first substring is denoted by using
+  the '0' (zero) integer value.
+
+Example:
+
+ [ get_attribute: [ my_server, data_endpoint, ip_address ], ':', 1 ]
+
+"""
+
+def validate(self):
+    if len(self.args) < 3:
+        ExceptionCollector.appendException(
+            ValueError(_('Invalid arguments for function "{0}". Expected '
+                         'at least three arguments.').format(TOKEN)))
+    else:
+        if not isinstance(self.args[1], str) or len(self.args[1]) != 1:
+            ExceptionCollector.appendException(
+                ValueError(_('Invalid arguments for function "{0}". '
+                             'Expected single char value as second '
+                             'argument.').format(TOKEN)))
+
+        if not isinstance(self.args[2], int):
+            ExceptionCollector.appendException(
+                ValueError(_('Invalid arguments for function "{0}". '
+                             'Expected integer value as third '
+                             'argument.').format(TOKEN)))
+
+def result(self):
+    return self
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/parameters/Input.java b/src/main/java/org/openecomp/sdc/toscaparser/api/parameters/Input.java
new file mode 100644
index 0000000..7b3e64f
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/parameters/Input.java
@@ -0,0 +1,226 @@
+package org.openecomp.sdc.toscaparser.api.parameters;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.DataEntity;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.EntityType;
+import org.openecomp.sdc.toscaparser.api.elements.constraints.Constraint;
+import org.openecomp.sdc.toscaparser.api.elements.constraints.Schema;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class Input {
+	
+	private static final String TYPE = "type";
+	private static final String DESCRIPTION = "description";
+	private static final String DEFAULT = "default";
+	private static final String CONSTRAINTS = "constraints";
+	private static final String REQUIRED = "required";
+	private static final String STATUS = "status";
+	private static final String ENTRY_SCHEMA = "entry_schema";
+	
+	public static final String INTEGER = "integer";
+	public static final String STRING = "string";
+	public static final String BOOLEAN = "boolean";
+	public static final String FLOAT = "float";
+	public static final String LIST = "list";
+	public static final String MAP = "map";
+	public static final String JSON = "json";
+    
+	private static String INPUTFIELD[] = {
+    		TYPE, DESCRIPTION, DEFAULT, CONSTRAINTS, REQUIRED,STATUS, ENTRY_SCHEMA
+    };
+	
+	private static String PRIMITIVE_TYPES[] = {
+			INTEGER, STRING, BOOLEAN, FLOAT, LIST, MAP, JSON
+    };
+    
+    private String name;
+    private Schema schema;
+	private LinkedHashMap<String,Object> customDefs;
+	
+	public Input(String _name,LinkedHashMap<String,Object> _schemaDict,LinkedHashMap<String,Object> _customDefs) {
+		name = _name;
+		schema = new Schema(_name,_schemaDict);
+		customDefs = _customDefs;
+	}
+	
+	public String getName() {
+		return name;
+	}
+
+	public String getType() {
+		return schema.getType();
+	}
+
+	public String getDescription() {
+		return schema.getDescription();
+	}
+
+	public boolean isRequired() {
+		return schema.isRequired();
+	}
+
+	public Object getDefault() {
+		return schema.getDefault();
+	}
+
+	public ArrayList<Constraint> getConstraints() {
+		return schema.getConstraints();
+	}
+
+    public void validate(Object value) {
+        _validateField();
+        _validateType(getType());
+        if(value != null) {
+            _validateValue(value);
+        }
+    }
+
+    private void _validateField() {
+    	for(String key: schema.getSchema().keySet()) {
+    		boolean bFound = false;
+    		for(String ifld: INPUTFIELD) {
+    			if(key.equals(ifld)) {
+    				bFound = true;
+    				break;
+    			}
+    		}
+    		if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                		"UnknownFieldError: Input \"%s\" contains unknown field \"%s\"",
+                		name,key));
+    		}
+    	}   		
+    }
+    
+    private void _validateType(String inputType) {
+		boolean bFound = false;
+		for(String pt: Schema.PROPERTY_TYPES) {
+			if(pt.equals(inputType)) {
+				bFound = true;
+				break;
+			}
+		}
+		
+		if(!bFound) {
+			if(customDefs.get(inputType) != null) {
+				bFound = true;
+			}
+		}
+		
+		if(!bFound) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "ValueError: Invalid type \"%s\"",inputType));
+		}
+    }
+    
+    private void _validateValue(Object value) {
+    	Object datatype = null;
+    	if(EntityType.TOSCA_DEF.get(getType()) != null) {
+    		datatype = EntityType.TOSCA_DEF.get(getType());
+    	}
+    	else if(EntityType.TOSCA_DEF.get(EntityType.DATATYPE_NETWORK_PREFIX + getType()) != null) {
+    		datatype = EntityType.TOSCA_DEF.get(EntityType.DATATYPE_NETWORK_PREFIX + getType());
+    	}
+    	
+    	String type = getType();
+    	// if it's one of the basic types DON'T look in customDefs
+    	if(Arrays.asList(PRIMITIVE_TYPES).contains(type)) {
+        	DataEntity.validateDatatype(getType(), value, null, (LinkedHashMap<String,Object>)datatype, null);
+        	return;	
+    	}
+    	else if(customDefs.get(getType()) != null) {
+    		datatype = customDefs.get(getType());
+        	DataEntity.validateDatatype(getType(), value, (LinkedHashMap<String,Object>)datatype, customDefs, null);
+        	return;
+    	}
+    	
+    	DataEntity.validateDatatype(getType(), value, null, (LinkedHashMap<String,Object>)datatype, null);
+    }
+}
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import MissingRequiredFieldError
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.dataentity import DataEntity
+from toscaparser.elements.constraints import Schema
+from toscaparser.elements.entity_type import EntityType
+from toscaparser.utils.gettextutils import _
+
+
+log = logging.getLogger('tosca')
+
+
+class Input(object):
+
+    INPUTFIELD = (TYPE, DESCRIPTION, DEFAULT, CONSTRAINTS, REQUIRED, STATUS,
+                  ENTRY_SCHEMA) = ('type', 'description', 'default',
+                                   'constraints', 'required', 'status',
+                                   'entry_schema')
+
+    def __init__(self, name, schema_dict):
+        self.name = name
+        self.schema = Schema(name, schema_dict)
+
+        self._validate_field()
+        self.validate_type(self.type)
+
+    @property
+    def type(self):
+        return self.schema.type
+
+    @property
+    def required(self):
+        return self.schema.required
+
+    @property
+    def description(self):
+        return self.schema.description
+
+    @property
+    def default(self):
+        return self.schema.default
+
+    @property
+    def constraints(self):
+        return self.schema.constraints
+
+    @property
+    def status(self):
+        return self.schema.status
+
+    def validate(self, value=None):
+        if value is not None:
+            self._validate_value(value)
+
+    def _validate_field(self):
+        for name in self.schema.schema:
+            if name not in self.INPUTFIELD:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Input "%s"' % self.name,
+                                      field=name))
+
+    def validate_type(self, input_type):
+        if input_type not in Schema.PROPERTY_TYPES:
+            ExceptionCollector.appendException(
+                ValueError(_('Invalid type "%s".') % type))
+
+    # tODO(anyone) Need to test for any built-in datatype not just network
+    # that is, tosca.datatypes.* and not assume tosca.datatypes.network.*
+    # tODO(anyone) Add support for tosca.datatypes.Credential
+    def _validate_value(self, value):
+        tosca = EntityType.TOSCA_DEF
+        datatype = None
+        if self.type in tosca:
+            datatype = tosca[self.type]
+        elif EntityType.DATATYPE_NETWORK_PREFIX + self.type in tosca:
+            datatype = tosca[EntityType.DATATYPE_NETWORK_PREFIX + self.type]
+
+        DataEntity.validate_datatype(self.type, value, None, datatype)
+
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/parameters/Output.java b/src/main/java/org/openecomp/sdc/toscaparser/api/parameters/Output.java
new file mode 100644
index 0000000..34ecf12
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/parameters/Output.java
@@ -0,0 +1,109 @@
+package org.openecomp.sdc.toscaparser.api.parameters;
+
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+
+public class Output {
+	
+	private static final String DESCRIPTION = "description";
+	public static final String VALUE = "value";
+	private static final String OUTPUTFIELD[] = {DESCRIPTION, VALUE};
+	
+	private String name;
+	private LinkedHashMap<String,Object> attrs;//TYPE???
+	
+	public Output(String oname,LinkedHashMap<String,Object> oattrs) {
+		name = oname;
+		attrs = oattrs;
+	}
+	
+	public String getDescription() {
+		return (String)attrs.get(DESCRIPTION);
+	}
+
+	public Object getValue() {
+		return attrs.get(VALUE);
+	}
+	
+	public void validate() {
+		_validateField();
+	}
+	
+	private void _validateField() {
+		if(!(attrs instanceof LinkedHashMap)) {
+			//TODO wrong error message...
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "ValidationError: Output \"%s\" has wrong type. Expecting a dict",
+                    name));
+		}
+		
+		if(getValue() == null) {
+            ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "MissingRequiredFieldError: Output \"%s\" is missing required \"%s\"",
+                    name,VALUE));
+		}
+        for(String key: attrs.keySet()) {
+    		boolean bFound = false;
+    		for(String of: OUTPUTFIELD) {
+    			if(key.equals(of)) {
+    				bFound = true;
+    				break;
+    			}
+    		}
+    		if(!bFound) {
+                ThreadLocalsHolder.getCollector().appendException(String.format(
+                    "UnknownFieldError: Output \"%s\" contains unknown field \"%s\"",
+                    name,key));
+            }
+        }
+	}
+	
+	// getter/setter
+	
+	public String getName() {
+		return name;
+	}
+	
+	public void setAttr(String name,Object value) {
+		attrs.put(name, value);
+	}
+}
+
+/*python
+
+class Output(object):
+
+    OUTPUTFIELD = (DESCRIPTION, VALUE) = ('description', 'value')
+
+    def __init__(self, name, attrs):
+        self.name = name
+        self.attrs = attrs
+
+    @property
+    def description(self):
+        return self.attrs.get(self.DESCRIPTION)
+
+    @property
+    def value(self):
+        return self.attrs.get(self.VALUE)
+
+    def validate(self):
+        self._validate_field()
+
+    def _validate_field(self):
+        if not isinstance(self.attrs, dict):
+            ExceptionCollector.appendException(
+                MissingRequiredFieldError(what='Output "%s"' % self.name,
+                                          required=self.VALUE))
+        if self.value is None:
+            ExceptionCollector.appendException(
+                MissingRequiredFieldError(what='Output "%s"' % self.name,
+                                          required=self.VALUE))
+        for name in self.attrs:
+            if name not in self.OUTPUTFIELD:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Output "%s"' % self.name,
+                                      field=name))
+*/
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/prereq/CSAR.java b/src/main/java/org/openecomp/sdc/toscaparser/api/prereq/CSAR.java
new file mode 100644
index 0000000..85b54ee
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/prereq/CSAR.java
@@ -0,0 +1,782 @@
+package org.openecomp.sdc.toscaparser.api.prereq;
+
+import java.io.BufferedOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.RandomAccessFile;
+import java.net.URL;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardCopyOption;
+import java.util.*;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipFile;
+import java.util.zip.ZipInputStream;
+
+import org.openecomp.sdc.toscaparser.api.ImportsLoader;
+import org.openecomp.sdc.toscaparser.api.common.JToscaException;
+import org.openecomp.sdc.toscaparser.api.utils.JToscaErrorCodes;
+import org.openecomp.sdc.toscaparser.api.utils.ThreadLocalsHolder;
+import org.openecomp.sdc.toscaparser.api.utils.UrlUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.yaml.snakeyaml.Yaml;
+
+public class CSAR {
+
+	private static Logger log = LoggerFactory.getLogger(CSAR.class.getName());
+	private static final ArrayList<String> META_PROPERTIES_FILES = new ArrayList<>(Arrays.asList("TOSCA-Metadata/TOSCA.meta", "csar.meta"));
+
+	private String path;
+    private boolean isFile;
+    private boolean isValidated;
+    private boolean errorCaught;
+    private String csar;
+    private String tempDir;
+//    private Metadata metaData;
+    private File tempFile;
+	private LinkedHashMap<String, LinkedHashMap<String, Object>> metaProperties;
+
+	public CSAR(String csarPath, boolean aFile) {
+		path = csarPath;
+		isFile = aFile;
+        isValidated = false;
+        errorCaught = false;
+        csar = null;
+        tempDir = null;
+        tempFile = null;
+		metaProperties = new LinkedHashMap<>();
+	}
+
+	@SuppressWarnings("unchecked")
+	public boolean validate() throws JToscaException {
+		isValidated = true;
+	
+        //validate that the file or URL exists
+        
+		if(isFile) {
+			File f = new File(path);
+			if (!f.isFile()) {
+				ThreadLocalsHolder.getCollector().appendException(String.format("\"%s\" is not a file", path));
+				return false;
+			} 
+			else {
+				this.csar = path; 
+			}
+		}
+		else {
+			if(!UrlUtils.validateUrl(path)) {
+				ThreadLocalsHolder.getCollector().appendException(String.format("ImportError: \"%s\" does not exist",path));
+				return false;
+			}
+			// get it to a local file
+			try {
+				File tempFile = File.createTempFile("csartmp",".csar");
+				Path ptf = Paths.get(tempFile.getPath());
+		 		URL webfile = new URL(path);
+		 		InputStream in = webfile.openStream();
+			    Files.copy(in,ptf,StandardCopyOption.REPLACE_EXISTING);
+			}
+			catch(Exception e) {
+				ThreadLocalsHolder.getCollector().appendException("ImportError: failed to load CSAR from " + path);
+				return false;
+			}
+			
+			log.debug("CSAR - validate - currently only files are supported");
+			return false;
+		}
+		
+		_parseAndValidateMetaProperties();
+
+		if(errorCaught) {
+			return false;
+		}
+		
+        // validate that external references in the main template actually exist and are accessible
+        _validateExternalReferences();
+        
+        return !errorCaught;
+
+	}
+
+	private void _parseAndValidateMetaProperties() throws JToscaException {
+
+		ZipFile zf = null;
+
+		try {
+
+			// validate that it is a valid zip file
+			RandomAccessFile raf = new RandomAccessFile(csar, "r");
+			long n = raf.readInt();
+			raf.close();
+			// check if Zip's magic number
+			if (n != 0x504B0304) {
+				String errorString = String.format("\"%s\" is not a valid zip file", csar);
+				log.error(errorString);
+				throw new JToscaException(errorString , JToscaErrorCodes.INVALID_CSAR_FORMAT.getValue());
+			}
+
+			// validate that it contains the metadata file in the correct location
+			zf = new ZipFile(csar);
+			ZipEntry ze = zf.getEntry("TOSCA-Metadata/TOSCA.meta");
+			if (ze == null) {
+				
+				String errorString = String.format(
+						"\"%s\" is not a valid CSAR as it does not contain the " +
+								"required file \"TOSCA.meta\" in the folder \"TOSCA-Metadata\"", csar);
+				log.error(errorString);
+				throw new JToscaException(errorString, JToscaErrorCodes.MISSING_META_FILE.getValue());
+			}
+
+			//Going over expected metadata files and parsing them
+			for (String metaFile: META_PROPERTIES_FILES) {
+
+				byte ba[] = new byte[4096];
+				ze = zf.getEntry(metaFile);
+				if (ze != null) {
+					InputStream inputStream = zf.getInputStream(ze);
+					n = inputStream.read(ba, 0, 4096);
+					String md = new String(ba);
+					md = md.substring(0, (int) n);
+					
+					String errorString = String.format(
+							"The file \"%s\" in the" +
+									" CSAR \"%s\" does not contain valid YAML content", ze.getName(), csar);
+					
+					try {
+						Yaml yaml = new Yaml();
+						Object mdo = yaml.load(md);
+						if (!(mdo instanceof LinkedHashMap)) {
+							log.error(errorString);
+							throw new JToscaException(errorString, JToscaErrorCodes.INVALID_META_YAML_CONTENT.getValue());
+						}
+
+						String[] split = ze.getName().split("/");
+	                    String fileName = split[split.length - 1];
+
+						if (!metaProperties.containsKey(fileName)) {
+							metaProperties.put(fileName, (LinkedHashMap<String, Object>) mdo);
+						}
+					}
+					catch(Exception e) {
+						log.error(errorString);
+						throw new JToscaException(errorString, JToscaErrorCodes.INVALID_META_YAML_CONTENT.getValue());
+					}
+				}
+			}
+
+			// verify it has "Entry-Definition"
+			String edf = _getMetadata("Entry-Definitions");
+			if (edf == null) {
+				String errorString = String.format(
+						"The CSAR \"%s\" is missing the required metadata " +
+								"\"Entry-Definitions\" in \"TOSCA-Metadata/TOSCA.meta\"", csar);
+				log.error(errorString);
+				throw new JToscaException(errorString, JToscaErrorCodes.ENTRY_DEFINITION_NOT_DEFINED.getValue());
+			}
+
+			//validate that "Entry-Definitions' metadata value points to an existing file in the CSAR
+			boolean foundEDF = false;
+			Enumeration<? extends ZipEntry> entries = zf.entries();
+			while (entries.hasMoreElements()) {
+				ze = entries.nextElement();
+				if (ze.getName().equals(edf)) {
+					foundEDF = true;
+					break;
+				}
+			}
+			if (!foundEDF) {
+				String errorString = String.format(
+						"The \"Entry-Definitions\" file defined in the CSAR \"%s\" does not exist", csar);
+				log.error(errorString);
+				throw new JToscaException(errorString, JToscaErrorCodes.MISSING_ENTRY_DEFINITION_FILE.getValue());
+			}
+		} catch (JToscaException e) {
+			//ThreadLocalsHolder.getCollector().appendCriticalException(e.getMessage());
+			throw e;
+		} catch (Exception e) {
+			ThreadLocalsHolder.getCollector().appendException("ValidationError: " + e.getMessage());
+			errorCaught = true;
+		}
+
+		try {
+			if (zf != null) {
+				zf.close();
+			}
+		} catch (IOException e) {
+		}
+	}
+	
+	public void cleanup() {
+		try {
+			if(tempFile != null) {
+				tempFile.delete();
+			}
+		}
+		catch(Exception e) {
+		}
+	}
+	
+    private String _getMetadata(String key) throws JToscaException {
+    	if(!isValidated) {
+    		validate();
+    	}
+    	Object value = _getMetaProperty("TOSCA.meta").get(key);
+    	return value != null ? value.toString() : null;
+    }
+
+    public String getAuthor() throws JToscaException {
+        return _getMetadata("Created-By");
+    }
+
+    public String getVersion() throws JToscaException {
+        return _getMetadata("CSAR-Version");
+    }
+
+	public LinkedHashMap<String, LinkedHashMap<String, Object>> getMetaProperties() {
+		return metaProperties;
+	}
+
+	private LinkedHashMap<String, Object> _getMetaProperty(String propertiesFile) {
+		return metaProperties.get(propertiesFile);
+	}
+
+	public String getMainTemplate() throws JToscaException {
+    	String entryDef = _getMetadata("Entry-Definitions");
+    	ZipFile zf;
+    	boolean ok = false;
+    	try {
+    		zf = new ZipFile(path);
+    		ok = (zf.getEntry(entryDef) != null);
+        	zf.close();
+    	}
+    	catch(IOException e) {
+    		if(!ok) {
+    			log.error("CSAR - getMainTemplate - failed to open {}", path);
+    		}
+    	}
+    	if(ok) {
+    	   	return entryDef;
+    	}
+    	else {
+    		return null;
+    	}
+    }
+
+	@SuppressWarnings("unchecked")
+	public LinkedHashMap<String,Object> getMainTemplateYaml() throws JToscaException {
+    	String mainTemplate = tempDir + File.separator + getMainTemplate();
+    	if(mainTemplate != null) {
+			try {
+	    		InputStream input = new FileInputStream(new File(mainTemplate));
+				Yaml yaml = new Yaml();
+				Object data = yaml.load(input);
+		        if(!(data instanceof LinkedHashMap)) {
+		        	throw new IOException();
+		        }
+		        return (LinkedHashMap<String,Object>)data;
+			}
+			catch(Exception e) {
+				ThreadLocalsHolder.getCollector().appendException(String.format(
+						"The file \"%s\" in the CSAR \"%s\" does not " +
+		                "contain valid TOSCA YAML content",
+		                mainTemplate,csar));
+			}
+    	}
+    	return null;
+    }
+    
+    public String getDescription() throws JToscaException {
+        String desc = _getMetadata("Description");
+        if(desc != null) {
+            return desc;
+        }
+
+		Map<String, Object> metaData = metaProperties.get("TOSCA.meta");
+		metaData.put("Description", getMainTemplateYaml().get("description"));
+		return _getMetadata("Description");
+    }
+
+    public String getTempDir() {
+    	return tempDir;
+    }
+        
+    public void decompress() throws IOException, JToscaException {
+        if(!isValidated) {
+            validate();
+        }
+       	tempDir = Files.createTempDirectory("JTP").toString();
+       	unzip(path,tempDir);
+       
+    }
+    
+	private void _validateExternalReferences() throws JToscaException {
+        // Extracts files referenced in the main template
+		// These references are currently supported:
+        // * imports
+        // * interface implementations
+        // * artifacts
+        try {
+            decompress();
+            String mainTplFile = getMainTemplate();
+            if(mainTplFile == null) {
+                return;
+            }
+            
+            LinkedHashMap<String,Object> mainTpl = getMainTemplateYaml();
+            if(mainTpl.get("imports") != null) {
+            	// this loads the imports
+            	ImportsLoader il = new ImportsLoader((ArrayList<Object>)mainTpl.get("imports"),
+            			                              tempDir + File.separator + mainTplFile,
+            			                              (Object)null,
+            			                              (LinkedHashMap<String,Object>)null);
+            }
+            
+            if(mainTpl.get("topology_template") != null) {
+            	LinkedHashMap<String,Object> topologyTemplate =
+            			(LinkedHashMap<String,Object>)mainTpl.get("topology_template");
+            	
+            	if(topologyTemplate.get("node_templates") != null) {
+                	LinkedHashMap<String,Object> nodeTemplates =
+                			(LinkedHashMap<String,Object>)topologyTemplate.get("node_templates");
+                	for(String nodeTemplateKey: nodeTemplates.keySet()) {
+                		LinkedHashMap<String,Object> nodeTemplate = 
+                				(LinkedHashMap<String,Object>)nodeTemplates.get(nodeTemplateKey);
+                		if(nodeTemplate.get("artifacts") != null) {
+                        	LinkedHashMap<String,Object> artifacts =
+                        			(LinkedHashMap<String,Object>)nodeTemplate.get("artifacts");
+                        	for(String artifactKey: artifacts.keySet()) {
+                        		Object artifact = artifacts.get(artifactKey);
+                        		if(artifact instanceof String) {
+                                    _validateExternalReference(mainTplFile,(String)artifact,true);
+                        		}
+                        		else if(artifact instanceof LinkedHashMap) {
+                        			String file = (String)((LinkedHashMap<String,Object>)artifact).get("file");
+                        			if(file != null) {
+                        				_validateExternalReference(mainTplFile,file,true);
+                        			}
+                        		}
+                        		else {
+                                    ThreadLocalsHolder.getCollector().appendException(String.format(
+                                        "ValueError: Unexpected artifact definition for \"%s\"",
+                                        artifactKey));
+                                        errorCaught = true;
+                        		}
+                        	}
+                		}
+                		if(nodeTemplate.get("interfaces") != null) {
+                        	LinkedHashMap<String,Object> interfaces =
+                        			(LinkedHashMap<String,Object>)nodeTemplate.get("interfaces");
+                        	for(String interfaceKey: interfaces.keySet()) {
+                        		LinkedHashMap<String,Object> _interface = 
+                        				(LinkedHashMap<String,Object>)interfaces.get(interfaceKey);
+                        		for(String operationKey: _interface.keySet()) {
+                        			Object operation = _interface.get(operationKey);
+	                        		if(operation instanceof String) {
+	                                    _validateExternalReference(mainTplFile,(String)operation,false);
+	                        		}
+	                        		else if(operation instanceof LinkedHashMap) {
+	                        			String imp = (String)((LinkedHashMap<String,Object>)operation).get("implementation");
+	                        			if(imp != null) {
+	                        				_validateExternalReference(mainTplFile,imp,true);
+	                        			}
+	                        		}
+                        		}
+                        	}
+                		}
+                	}
+            	}
+            }
+        }
+        catch(IOException e) {
+        	errorCaught = true;
+        }
+        finally {
+        	// delete tempDir (only here?!?)
+        	File fdir = new File(tempDir);
+        	deleteDir(fdir);
+        	tempDir = null;
+        }
+	}
+	
+	public static void deleteDir(File fdir) {
+		try {
+		  if (fdir.isDirectory()) {
+		    for (File c : fdir.listFiles())
+		      deleteDir(c);
+		  }
+		  fdir.delete();
+		}
+		catch(Exception e) {
+		}
+	}
+	
+	private void _validateExternalReference(String tplFile,String resourceFile,boolean raiseExc) {
+        // Verify that the external resource exists
+
+        // If resource_file is a URL verify that the URL is valid.
+        // If resource_file is a relative path verify that the path is valid
+        // considering base folder (self.temp_dir) and tpl_file.
+        // Note that in a CSAR resource_file cannot be an absolute path.
+        if(UrlUtils.validateUrl(resourceFile)) {
+            String msg = String.format("URLException: The resource at \"%s\" cannot be accessed",resourceFile);
+            try {
+                if(UrlUtils.isUrlAccessible(resourceFile)) {
+                    return;
+                }
+                else {
+                    ThreadLocalsHolder.getCollector().appendException(msg);
+                    errorCaught = true;
+                }
+            }
+            catch (Exception e) {
+				ThreadLocalsHolder.getCollector().appendException(msg);
+            }
+        }
+
+    	String dirPath = Paths.get(tplFile).getParent().toString();
+    	String filePath = tempDir + File.separator + dirPath + File.separator + resourceFile;
+    	File f = new File(filePath);
+    	if(f.isFile()) {
+    		return;
+    	}
+    	
+		if(raiseExc) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+				"ValueError: The resource \"%s\" does not exist",resourceFile));
+		}
+		errorCaught = true;
+	}
+	
+    private void unzip(String zipFilePath, String destDirectory) throws IOException {
+        File destDir = new File(destDirectory);
+        if (!destDir.exists()) {
+            destDir.mkdir();
+        }
+        ZipInputStream zipIn = new ZipInputStream(new FileInputStream(zipFilePath));
+        ZipEntry entry = zipIn.getNextEntry();
+        // iterates over entries in the zip file
+        while (entry != null) {
+        	// create all directories needed for nested items
+        	String[] parts = entry.getName().split("/");
+        	String s = destDirectory + File.separator ;
+        	for(int i=0; i< parts.length-1; i++) {
+        		s += parts[i];
+        		File idir = new File(s);
+        		if(!idir.exists()) {
+        			idir.mkdir();
+        		}
+        		s += File.separator;
+        	}
+            String filePath = destDirectory + File.separator + entry.getName();
+            if (!entry.isDirectory()) {
+                // if the entry is a file, extracts it
+                extractFile(zipIn, filePath);
+            } else {
+                // if the entry is a directory, make the directory
+                File dir = new File(filePath);
+                dir.mkdir();
+            }
+            zipIn.closeEntry();
+            entry = zipIn.getNextEntry();
+        }
+        zipIn.close();
+    }
+    
+    /**
+     * Extracts a zip entry (file entry)
+     * @param zipIn
+     * @param filePath
+     * @throws IOException
+     */
+    private static final int BUFFER_SIZE = 4096;
+    
+    private void extractFile(ZipInputStream zipIn, String filePath) throws IOException {
+        //BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(filePath));
+    	FileOutputStream fos = new FileOutputStream(filePath);
+    	BufferedOutputStream bos = new BufferedOutputStream(fos);
+        byte[] bytesIn = new byte[BUFFER_SIZE];
+        int read = 0;
+        while ((read = zipIn.read(bytesIn)) != -1) {
+            bos.write(bytesIn, 0, read);
+        }
+        bos.close();
+    }
+
+}	
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import URLException
+from toscaparser.common.exception import ValidationError
+from toscaparser.imports import ImportsLoader
+from toscaparser.utils.gettextutils import _
+from toscaparser.utils.urlutils import UrlUtils
+
+try:  # Python 2.x
+    from BytesIO import BytesIO
+except ImportError:  # Python 3.x
+    from io import BytesIO
+
+
+class CSAR(object):
+
+    def __init__(self, csar_file, a_file=True):
+        self.path = csar_file
+        self.a_file = a_file
+        self.is_validated = False
+        self.error_caught = False
+        self.csar = None
+        self.temp_dir = None
+
+    def validate(self):
+        """Validate the provided CSAR file."""
+
+        self.is_validated = True
+
+        # validate that the file or URL exists
+        missing_err_msg = (_('"%s" does not exist.') % self.path)
+        if self.a_file:
+            if not os.path.isfile(self.path):
+                ExceptionCollector.appendException(
+                    ValidationError(message=missing_err_msg))
+                return False
+            else:
+                self.csar = self.path
+        else:  # a URL
+            if not UrlUtils.validate_url(self.path):
+                ExceptionCollector.appendException(
+                    ValidationError(message=missing_err_msg))
+                return False
+            else:
+                response = requests.get(self.path)
+                self.csar = BytesIO(response.content)
+
+        # validate that it is a valid zip file
+        if not zipfile.is_zipfile(self.csar):
+            err_msg = (_('"%s" is not a valid zip file.') % self.path)
+            ExceptionCollector.appendException(
+                ValidationError(message=err_msg))
+            return False
+
+        # validate that it contains the metadata file in the correct location
+        self.zfile = zipfile.ZipFile(self.csar, 'r')
+        filelist = self.zfile.namelist()
+        if 'TOSCA-Metadata/TOSCA.meta' not in filelist:
+            err_msg = (_('"%s" is not a valid CSAR as it does not contain the '
+                         'required file "TOSCA.meta" in the folder '
+                         '"TOSCA-Metadata".') % self.path)
+            ExceptionCollector.appendException(
+                ValidationError(message=err_msg))
+            return False
+
+        # validate that 'Entry-Definitions' property exists in TOSCA.meta
+        data = self.zfile.read('TOSCA-Metadata/TOSCA.meta')
+        invalid_yaml_err_msg = (_('The file "TOSCA-Metadata/TOSCA.meta" in '
+                                  'the CSAR "%s" does not contain valid YAML '
+                                  'content.') % self.path)
+        try:
+            meta = yaml.load(data)
+            if type(meta) is dict:
+                self.metadata = meta
+            else:
+                ExceptionCollector.appendException(
+                    ValidationError(message=invalid_yaml_err_msg))
+                return False
+        except yaml.YAMLError:
+            ExceptionCollector.appendException(
+                ValidationError(message=invalid_yaml_err_msg))
+            return False
+
+        if 'Entry-Definitions' not in self.metadata:
+            err_msg = (_('The CSAR "%s" is missing the required metadata '
+                         '"Entry-Definitions" in '
+                         '"TOSCA-Metadata/TOSCA.meta".')
+                       % self.path)
+            ExceptionCollector.appendException(
+                ValidationError(message=err_msg))
+            return False
+
+        # validate that 'Entry-Definitions' metadata value points to an
+        # existing file in the CSAR
+        entry = self.metadata.get('Entry-Definitions')
+        if entry and entry not in filelist:
+            err_msg = (_('The "Entry-Definitions" file defined in the '
+                         'CSAR "%s" does not exist.') % self.path)
+            ExceptionCollector.appendException(
+                ValidationError(message=err_msg))
+            return False
+
+        # validate that external references in the main template actually
+        # exist and are accessible
+        self._validate_external_references()
+        return not self.error_caught
+
+    def get_metadata(self):
+        """Return the metadata dictionary."""
+
+        # validate the csar if not already validated
+        if not self.is_validated:
+            self.validate()
+
+        # return a copy to avoid changes overwrite the original
+        return dict(self.metadata) if self.metadata else None
+
+    def _get_metadata(self, key):
+        if not self.is_validated:
+            self.validate()
+        return self.metadata.get(key)
+
+    def get_author(self):
+        return self._get_metadata('Created-By')
+
+    def get_version(self):
+        return self._get_metadata('CSAR-Version')
+
+    def get_main_template(self):
+        entry_def = self._get_metadata('Entry-Definitions')
+        if entry_def in self.zfile.namelist():
+            return entry_def
+
+    def get_main_template_yaml(self):
+        main_template = self.get_main_template()
+        if main_template:
+            data = self.zfile.read(main_template)
+            invalid_tosca_yaml_err_msg = (
+                _('The file "%(template)s" in the CSAR "%(csar)s" does not '
+                  'contain valid TOSCA YAML content.') %
+                {'template': main_template, 'csar': self.path})
+            try:
+                tosca_yaml = yaml.load(data)
+                if type(tosca_yaml) is not dict:
+                    ExceptionCollector.appendException(
+                        ValidationError(message=invalid_tosca_yaml_err_msg))
+                return tosca_yaml
+            except Exception:
+                ExceptionCollector.appendException(
+                    ValidationError(message=invalid_tosca_yaml_err_msg))
+
+    def get_description(self):
+        desc = self._get_metadata('Description')
+        if desc is not None:
+            return desc
+
+        self.metadata['Description'] = \
+            self.get_main_template_yaml().get('description')
+        return self.metadata['Description']
+
+    def decompress(self):
+        if not self.is_validated:
+            self.validate()
+        self.temp_dir = tempfile.NamedTemporaryFile().name
+        with zipfile.ZipFile(self.csar, "r") as zf:
+            zf.extractall(self.temp_dir)
+
+    def _validate_external_references(self):
+        """Extracts files referenced in the main template
+
+        These references are currently supported:
+        * imports
+        * interface implementations
+        * artifacts
+        """
+        try:
+            self.decompress()
+            main_tpl_file = self.get_main_template()
+            if not main_tpl_file:
+                return
+            main_tpl = self.get_main_template_yaml()
+
+            if 'imports' in main_tpl:
+                ImportsLoader(main_tpl['imports'],
+                              os.path.join(self.temp_dir, main_tpl_file))
+
+            if 'topology_template' in main_tpl:
+                topology_template = main_tpl['topology_template']
+
+                if 'node_templates' in topology_template:
+                    node_templates = topology_template['node_templates']
+
+                    for node_template_key in node_templates:
+                        node_template = node_templates[node_template_key]
+                        if 'artifacts' in node_template:
+                            artifacts = node_template['artifacts']
+                            for artifact_key in artifacts:
+                                artifact = artifacts[artifact_key]
+                                if isinstance(artifact, six.string_types):
+                                    self._validate_external_reference(
+                                        main_tpl_file,
+                                        artifact)
+                                elif isinstance(artifact, dict):
+                                    if 'file' in artifact:
+                                        self._validate_external_reference(
+                                            main_tpl_file,
+                                            artifact['file'])
+                                else:
+                                    ExceptionCollector.appendException(
+                                        ValueError(_('Unexpected artifact '
+                                                     'definition for "%s".')
+                                                   % artifact_key))
+                                    self.error_caught = True
+                        if 'interfaces' in node_template:
+                            interfaces = node_template['interfaces']
+                            for interface_key in interfaces:
+                                interface = interfaces[interface_key]
+                                for opertation_key in interface:
+                                    operation = interface[opertation_key]
+                                    if isinstance(operation, six.string_types):
+                                        self._validate_external_reference(
+                                            main_tpl_file,
+                                            operation,
+                                            False)
+                                    elif isinstance(operation, dict):
+                                        if 'implementation' in operation:
+                                            self._validate_external_reference(
+                                                main_tpl_file,
+                                                operation['implementation'])
+        finally:
+            if self.temp_dir:
+                shutil.rmtree(self.temp_dir)
+
+    def _validate_external_reference(self, tpl_file, resource_file,
+                                     raise_exc=True):
+        """Verify that the external resource exists
+
+        If resource_file is a URL verify that the URL is valid.
+        If resource_file is a relative path verify that the path is valid
+        considering base folder (self.temp_dir) and tpl_file.
+        Note that in a CSAR resource_file cannot be an absolute path.
+        """
+        if UrlUtils.validate_url(resource_file):
+            msg = (_('The resource at "%s" cannot be accessed.') %
+                   resource_file)
+            try:
+                if UrlUtils.url_accessible(resource_file):
+                    return
+                else:
+                    ExceptionCollector.appendException(
+                        URLException(what=msg))
+                    self.error_caught = True
+            except Exception:
+                ExceptionCollector.appendException(
+                    URLException(what=msg))
+                self.error_caught = True
+
+        if os.path.isfile(os.path.join(self.temp_dir,
+                                       os.path.dirname(tpl_file),
+                                       resource_file)):
+            return
+
+        if raise_exc:
+            ExceptionCollector.appendException(
+                ValueError(_('The resource "%s" does not exist.')
+                           % resource_file))
+            self.error_caught = True
+*/
+
+
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/prereq/CSAR.java.orig b/src/main/java/org/openecomp/sdc/toscaparser/api/prereq/CSAR.java.orig
new file mode 100644
index 0000000..aa36b9e
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/prereq/CSAR.java.orig
@@ -0,0 +1,767 @@
+package org.openecomp.sdc.toscaparser.api.prereq;
+
+import java.io.BufferedOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.RandomAccessFile;
+import java.net.URL;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardCopyOption;
+import java.util.*;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipFile;
+import java.util.zip.ZipInputStream;
+
+import org.openecomp.sdc.toscaparser.api.ImportsLoader;
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.api.elements.Metadata;
+import org.openecomp.sdc.toscaparser.api.utils.UrlUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.yaml.snakeyaml.Yaml;
+
+<<<<<<< HEAD:jtosca/src/main/java/org/openecomp/sdc/toscaparser/prereq/CSAR.java
+import org.openecomp.sdc.toscaparser.ImportsLoader;
+import org.openecomp.sdc.toscaparser.common.ExceptionCollector;
+import org.openecomp.sdc.toscaparser.utils.UrlUtils;
+
+=======
+>>>>>>> 243072-jtosca-package-fix:jtosca/src/main/java/org/openecomp/sdc/toscaparser/api/prereq/CSAR.java
+public class CSAR {
+
+	private static Logger log = LoggerFactory.getLogger(CSAR.class.getName());
+	private static final ArrayList<String> META_PROPERTIES_FILES = new ArrayList<>(Arrays.asList("TOSCA-Metadata/TOSCA.meta", "csar.meta"));
+
+	private String path;
+    private boolean isFile;
+    private boolean isValidated;
+    private boolean errorCaught;
+    private String csar;
+    private String tempDir;
+//    private Metadata metaData;
+    private File tempFile;
+	private LinkedHashMap<String, LinkedHashMap<String, Object>> metaProperties;
+
+	public CSAR(String csarPath, boolean aFile) {
+		path = csarPath;
+		isFile = aFile;
+        isValidated = false;
+        errorCaught = false;
+        csar = null;
+        tempDir = null;
+        tempFile = null;
+		metaProperties = new LinkedHashMap<>();
+	}
+
+	@SuppressWarnings("unchecked")
+	public boolean validate() {
+		isValidated = true;
+	
+        //validate that the file or URL exists
+        
+		if(isFile) {
+			File f = new File(path);
+			if (!f.isFile()) {
+				ExceptionCollector.appendException(String.format("\"%s\" is not a file", path));
+				return false;
+			} 
+			else {
+				this.csar = path; 
+			}
+		}
+		else {
+			if(!UrlUtils.validateUrl(path)) {
+				ExceptionCollector.appendException(String.format("ImportError: \"%s\" does not exist",path));
+				return false;
+			}
+			// get it to a local file
+			try {
+				File tempFile = File.createTempFile("csartmp",".csar");
+				Path ptf = Paths.get(tempFile.getPath());
+		 		URL webfile = new URL(path);
+		 		InputStream in = webfile.openStream();
+			    Files.copy(in,ptf,StandardCopyOption.REPLACE_EXISTING);
+			}
+			catch(Exception e) {
+				ExceptionCollector.appendException("ImportError: failed to load CSAR from " + path);
+				return false;
+			}
+			
+			log.debug("CSAR - validate - currently only files are supported");
+			return false;
+		}
+		
+		_parseAndValidateMetaProperties();
+
+		if(errorCaught) {
+			return false;
+		}
+		
+        // validate that external references in the main template actually exist and are accessible
+        _validateExternalReferences();
+        
+        return !errorCaught;
+
+	}
+
+	private void _parseAndValidateMetaProperties() {
+
+		ZipFile zf = null;
+
+		try {
+
+			// validate that it is a valid zip file
+			RandomAccessFile raf = new RandomAccessFile(csar, "r");
+			long n = raf.readInt();
+			raf.close();
+			// check if Zip's magic number
+			if (n != 0x504B0304) {
+				throw new IOException(String.format("\"%s\" is not a valid zip file", csar));
+			}
+
+			// validate that it contains the metadata file in the correct location
+			zf = new ZipFile(csar);
+			ZipEntry ze = zf.getEntry("TOSCA-Metadata/TOSCA.meta");
+			if (ze == null) {
+				throw new IOException(String.format(
+						"\"%s\" is not a valid CSAR as it does not contain the " +
+								"required file \"TOSCA.meta\" in the folder \"TOSCA-Metadata\"", csar));
+			}
+
+			//Going over expected metadata files and parsing them
+			for (String metaFile: META_PROPERTIES_FILES) {
+
+				byte ba[] = new byte[4096];
+				ze = zf.getEntry(metaFile);
+				if (ze != null) {
+					InputStream inputStream = zf.getInputStream(ze);
+					n = inputStream.read(ba, 0, 4096);
+
+					String md = new String(ba);
+					md = md.substring(0, (int) n);
+					Yaml yaml = new Yaml();
+					Object mdo = yaml.load(md);
+					if (!(mdo instanceof LinkedHashMap)) {
+						throw new IOException(String.format(
+								"The file \"%s\" in the" +
+										" CSAR \"%s\" does not contain valid YAML content", ze.getName(), csar));
+					}
+
+					String[] split = ze.getName().split("/");
+                    String fileName = split[split.length - 1];
+
+					if (!metaProperties.containsKey(fileName)) {
+						metaProperties.put(fileName, (LinkedHashMap<String, Object>) mdo);
+					}
+				}
+			}
+
+			// verify it has "Entry-Definition"
+			String edf = _getMetadata("Entry-Definitions");
+			if (edf == null) {
+				throw new IOException(String.format(
+						"The CSAR \"%s\" is missing the required metadata " +
+								"\"Entry-Definitions\" in \"TOSCA-Metadata/TOSCA.meta\"", csar));
+			}
+
+			//validate that "Entry-Definitions' metadata value points to an existing file in the CSAR
+			boolean foundEDF = false;
+			Enumeration<? extends ZipEntry> entries = zf.entries();
+			while (entries.hasMoreElements()) {
+				ze = entries.nextElement();
+				if (ze.getName().equals(edf)) {
+					foundEDF = true;
+					break;
+				}
+			}
+			if (!foundEDF) {
+				throw new IOException(String.format(
+						"The \"Entry-Definitions\" file defined in the CSAR \"%s\" does not exist", csar));
+			}
+		} catch (Exception e) {
+			ExceptionCollector.appendException("ValidationError: " + e.getMessage());
+			errorCaught = true;
+		}
+
+		try {
+			if (zf != null) {
+				zf.close();
+			}
+		} catch (IOException e) {
+		}
+	}
+	
+	public void cleanup() {
+		try {
+			if(tempFile != null) {
+				tempFile.delete();
+			}
+		}
+		catch(Exception e) {
+		}
+	}
+	
+    private String _getMetadata(String key) {
+    	if(!isValidated) {
+    		validate();
+    	}
+    	Object value = _getMetaProperty("TOSCA.meta").get(key);
+    	return value != null ? value.toString() : null;
+    }
+
+    public String getAuthor() {
+        return _getMetadata("Created-By");
+    }
+
+    public String getVersion() {
+        return _getMetadata("CSAR-Version");
+    }
+
+	public LinkedHashMap<String, LinkedHashMap<String, Object>> getMetaProperties() {
+		return metaProperties;
+	}
+
+	private LinkedHashMap<String, Object> _getMetaProperty(String propertiesFile) {
+		return metaProperties.get(propertiesFile);
+	}
+
+	public String getMainTemplate() {
+    	String entryDef = _getMetadata("Entry-Definitions");
+    	ZipFile zf;
+    	boolean ok = false;
+    	try {
+    		zf = new ZipFile(path);
+    		ok = (zf.getEntry(entryDef) != null);
+        	zf.close();
+    	}
+    	catch(IOException e) {
+    		if(!ok) {
+    			log.error("CSAR - getMainTemplate - failed to open {}", path);
+    		}
+    	}
+    	if(ok) {
+    	   	return entryDef;
+    	}
+    	else {
+    		return null;
+    	}
+    }
+
+	@SuppressWarnings("unchecked")
+	public LinkedHashMap<String,Object> getMainTemplateYaml() {
+    	String mainTemplate = tempDir + File.separator + getMainTemplate();
+    	if(mainTemplate != null) {
+			try {
+	    		InputStream input = new FileInputStream(new File(mainTemplate));
+				Yaml yaml = new Yaml();
+				Object data = yaml.load(input);
+		        if(!(data instanceof LinkedHashMap)) {
+		        	throw new IOException();
+		        }
+		        return (LinkedHashMap<String,Object>)data;
+			}
+			catch(Exception e) {
+				ExceptionCollector.appendException(String.format(
+						"The file \"%s\" in the CSAR \"%s\" does not " +
+		                "contain valid TOSCA YAML content",
+		                mainTemplate,csar));
+			}
+    	}
+    	return null;
+    }
+    
+    public String getDescription() {
+        String desc = _getMetadata("Description");
+        if(desc != null) {
+            return desc;
+        }
+
+		Map<String, Object> metaData = metaProperties.get("TOSCA.meta");
+		metaData.put("Description", getMainTemplateYaml().get("description"));
+		return _getMetadata("Description");
+    }
+
+    public String getTempDir() {
+    	return tempDir;
+    }
+        
+    public void decompress() throws IOException {
+        if(!isValidated) {
+            validate();
+        }
+       	tempDir = Files.createTempDirectory("JTP").toString();
+       	unzip(path,tempDir);
+       
+    }
+    
+	private void _validateExternalReferences() {
+        // Extracts files referenced in the main template
+		// These references are currently supported:
+        // * imports
+        // * interface implementations
+        // * artifacts
+        try {
+            decompress();
+            String mainTplFile = getMainTemplate();
+            if(mainTplFile == null) {
+                return;
+            }
+            
+            LinkedHashMap<String,Object> mainTpl = getMainTemplateYaml();
+            if(mainTpl.get("imports") != null) {
+            	// this loads the imports
+            	ImportsLoader il = new ImportsLoader((ArrayList<Object>)mainTpl.get("imports"),
+            			                              tempDir + File.separator + mainTplFile,
+            			                              (Object)null,
+            			                              (LinkedHashMap<String,Object>)null);
+            }
+            
+            if(mainTpl.get("topology_template") != null) {
+            	LinkedHashMap<String,Object> topologyTemplate =
+            			(LinkedHashMap<String,Object>)mainTpl.get("topology_template");
+            	
+            	if(topologyTemplate.get("node_templates") != null) {
+                	LinkedHashMap<String,Object> nodeTemplates =
+                			(LinkedHashMap<String,Object>)topologyTemplate.get("node_templates");
+                	for(String nodeTemplateKey: nodeTemplates.keySet()) {
+                		LinkedHashMap<String,Object> nodeTemplate = 
+                				(LinkedHashMap<String,Object>)nodeTemplates.get(nodeTemplateKey);
+                		if(nodeTemplate.get("artifacts") != null) {
+                        	LinkedHashMap<String,Object> artifacts =
+                        			(LinkedHashMap<String,Object>)nodeTemplate.get("artifacts");
+                        	for(String artifactKey: artifacts.keySet()) {
+                        		Object artifact = artifacts.get(artifactKey);
+                        		if(artifact instanceof String) {
+                                    _validateExternalReference(mainTplFile,(String)artifact,true);
+                        		}
+                        		else if(artifact instanceof LinkedHashMap) {
+                        			String file = (String)((LinkedHashMap<String,Object>)artifact).get("file");
+                        			if(file != null) {
+                        				_validateExternalReference(mainTplFile,file,true);
+                        			}
+                        		}
+                        		else {
+                                    ExceptionCollector.appendException(String.format(
+                                        "ValueError: Unexpected artifact definition for \"%s\"",
+                                        artifactKey));
+                                        errorCaught = true;
+                        		}
+                        	}
+                		}
+                		if(nodeTemplate.get("interfaces") != null) {
+                        	LinkedHashMap<String,Object> interfaces =
+                        			(LinkedHashMap<String,Object>)nodeTemplate.get("interfaces");
+                        	for(String interfaceKey: interfaces.keySet()) {
+                        		LinkedHashMap<String,Object> _interface = 
+                        				(LinkedHashMap<String,Object>)interfaces.get(interfaceKey);
+                        		for(String operationKey: _interface.keySet()) {
+                        			Object operation = _interface.get(operationKey);
+	                        		if(operation instanceof String) {
+	                                    _validateExternalReference(mainTplFile,(String)operation,false);
+	                        		}
+	                        		else if(operation instanceof LinkedHashMap) {
+	                        			String imp = (String)((LinkedHashMap<String,Object>)operation).get("implementation");
+	                        			if(imp != null) {
+	                        				_validateExternalReference(mainTplFile,imp,true);
+	                        			}
+	                        		}
+                        		}
+                        	}
+                		}
+                	}
+            	}
+            }
+        }
+        catch(IOException e) {
+        	errorCaught = true;
+        }
+        finally {
+        	// delete tempDir (only here?!?)
+        	File fdir = new File(tempDir);
+        	deleteDir(fdir);
+        	tempDir = null;
+        }
+	}
+	
+	public static void deleteDir(File fdir) {
+		try {
+		  if (fdir.isDirectory()) {
+		    for (File c : fdir.listFiles())
+		      deleteDir(c);
+		  }
+		  fdir.delete();
+		}
+		catch(Exception e) {
+		}
+	}
+	
+	private void _validateExternalReference(String tplFile,String resourceFile,boolean raiseExc) {
+        // Verify that the external resource exists
+
+        // If resource_file is a URL verify that the URL is valid.
+        // If resource_file is a relative path verify that the path is valid
+        // considering base folder (self.temp_dir) and tpl_file.
+        // Note that in a CSAR resource_file cannot be an absolute path.
+        if(UrlUtils.validateUrl(resourceFile)) {
+            String msg = String.format("URLException: The resource at \"%s\" cannot be accessed",resourceFile);
+            try {
+                if(UrlUtils.isUrlAccessible(resourceFile)) {
+                    return;
+                }
+                else {
+                    ExceptionCollector.appendException(msg);
+                    errorCaught = true;
+                }
+            }
+            catch (Exception e) {
+                ExceptionCollector.appendException(msg);
+            }
+        }
+
+    	String dirPath = Paths.get(tplFile).getParent().toString();
+    	String filePath = tempDir + File.separator + dirPath + File.separator + resourceFile;
+    	File f = new File(filePath);
+    	if(f.isFile()) {
+    		return;
+    	}
+    	
+		if(raiseExc) {
+			ExceptionCollector.appendException(String.format(
+				"ValueError: The resource \"%s\" does not exist",resourceFile));
+		}
+		errorCaught = true;
+	}
+	
+    private void unzip(String zipFilePath, String destDirectory) throws IOException {
+        File destDir = new File(destDirectory);
+        if (!destDir.exists()) {
+            destDir.mkdir();
+        }
+        ZipInputStream zipIn = new ZipInputStream(new FileInputStream(zipFilePath));
+        ZipEntry entry = zipIn.getNextEntry();
+        // iterates over entries in the zip file
+        while (entry != null) {
+        	// create all directories needed for nested items
+        	String[] parts = entry.getName().split("/");
+        	String s = destDirectory + File.separator ;
+        	for(int i=0; i< parts.length-1; i++) {
+        		s += parts[i];
+        		File idir = new File(s);
+        		if(!idir.exists()) {
+        			idir.mkdir();
+        		}
+        		s += File.separator;
+        	}
+            String filePath = destDirectory + File.separator + entry.getName();
+            if (!entry.isDirectory()) {
+                // if the entry is a file, extracts it
+                extractFile(zipIn, filePath);
+            } else {
+                // if the entry is a directory, make the directory
+                File dir = new File(filePath);
+                dir.mkdir();
+            }
+            zipIn.closeEntry();
+            entry = zipIn.getNextEntry();
+        }
+        zipIn.close();
+    }
+    
+    /**
+     * Extracts a zip entry (file entry)
+     * @param zipIn
+     * @param filePath
+     * @throws IOException
+     */
+    private static final int BUFFER_SIZE = 4096;
+    
+    private void extractFile(ZipInputStream zipIn, String filePath) throws IOException {
+        //BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(filePath));
+    	FileOutputStream fos = new FileOutputStream(filePath);
+    	BufferedOutputStream bos = new BufferedOutputStream(fos);
+        byte[] bytesIn = new byte[BUFFER_SIZE];
+        int read = 0;
+        while ((read = zipIn.read(bytesIn)) != -1) {
+            bos.write(bytesIn, 0, read);
+        }
+        bos.close();
+    }
+
+}	
+
+/*python
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import URLException
+from toscaparser.common.exception import ValidationError
+from toscaparser.imports import ImportsLoader
+from toscaparser.utils.gettextutils import _
+from toscaparser.utils.urlutils import UrlUtils
+
+try:  # Python 2.x
+    from BytesIO import BytesIO
+except ImportError:  # Python 3.x
+    from io import BytesIO
+
+
+class CSAR(object):
+
+    def __init__(self, csar_file, a_file=True):
+        self.path = csar_file
+        self.a_file = a_file
+        self.is_validated = False
+        self.error_caught = False
+        self.csar = None
+        self.temp_dir = None
+
+    def validate(self):
+        """Validate the provided CSAR file."""
+
+        self.is_validated = True
+
+        # validate that the file or URL exists
+        missing_err_msg = (_('"%s" does not exist.') % self.path)
+        if self.a_file:
+            if not os.path.isfile(self.path):
+                ExceptionCollector.appendException(
+                    ValidationError(message=missing_err_msg))
+                return False
+            else:
+                self.csar = self.path
+        else:  # a URL
+            if not UrlUtils.validate_url(self.path):
+                ExceptionCollector.appendException(
+                    ValidationError(message=missing_err_msg))
+                return False
+            else:
+                response = requests.get(self.path)
+                self.csar = BytesIO(response.content)
+
+        # validate that it is a valid zip file
+        if not zipfile.is_zipfile(self.csar):
+            err_msg = (_('"%s" is not a valid zip file.') % self.path)
+            ExceptionCollector.appendException(
+                ValidationError(message=err_msg))
+            return False
+
+        # validate that it contains the metadata file in the correct location
+        self.zfile = zipfile.ZipFile(self.csar, 'r')
+        filelist = self.zfile.namelist()
+        if 'TOSCA-Metadata/TOSCA.meta' not in filelist:
+            err_msg = (_('"%s" is not a valid CSAR as it does not contain the '
+                         'required file "TOSCA.meta" in the folder '
+                         '"TOSCA-Metadata".') % self.path)
+            ExceptionCollector.appendException(
+                ValidationError(message=err_msg))
+            return False
+
+        # validate that 'Entry-Definitions' property exists in TOSCA.meta
+        data = self.zfile.read('TOSCA-Metadata/TOSCA.meta')
+        invalid_yaml_err_msg = (_('The file "TOSCA-Metadata/TOSCA.meta" in '
+                                  'the CSAR "%s" does not contain valid YAML '
+                                  'content.') % self.path)
+        try:
+            meta = yaml.load(data)
+            if type(meta) is dict:
+                self.metadata = meta
+            else:
+                ExceptionCollector.appendException(
+                    ValidationError(message=invalid_yaml_err_msg))
+                return False
+        except yaml.YAMLError:
+            ExceptionCollector.appendException(
+                ValidationError(message=invalid_yaml_err_msg))
+            return False
+
+        if 'Entry-Definitions' not in self.metadata:
+            err_msg = (_('The CSAR "%s" is missing the required metadata '
+                         '"Entry-Definitions" in '
+                         '"TOSCA-Metadata/TOSCA.meta".')
+                       % self.path)
+            ExceptionCollector.appendException(
+                ValidationError(message=err_msg))
+            return False
+
+        # validate that 'Entry-Definitions' metadata value points to an
+        # existing file in the CSAR
+        entry = self.metadata.get('Entry-Definitions')
+        if entry and entry not in filelist:
+            err_msg = (_('The "Entry-Definitions" file defined in the '
+                         'CSAR "%s" does not exist.') % self.path)
+            ExceptionCollector.appendException(
+                ValidationError(message=err_msg))
+            return False
+
+        # validate that external references in the main template actually
+        # exist and are accessible
+        self._validate_external_references()
+        return not self.error_caught
+
+    def get_metadata(self):
+        """Return the metadata dictionary."""
+
+        # validate the csar if not already validated
+        if not self.is_validated:
+            self.validate()
+
+        # return a copy to avoid changes overwrite the original
+        return dict(self.metadata) if self.metadata else None
+
+    def _get_metadata(self, key):
+        if not self.is_validated:
+            self.validate()
+        return self.metadata.get(key)
+
+    def get_author(self):
+        return self._get_metadata('Created-By')
+
+    def get_version(self):
+        return self._get_metadata('CSAR-Version')
+
+    def get_main_template(self):
+        entry_def = self._get_metadata('Entry-Definitions')
+        if entry_def in self.zfile.namelist():
+            return entry_def
+
+    def get_main_template_yaml(self):
+        main_template = self.get_main_template()
+        if main_template:
+            data = self.zfile.read(main_template)
+            invalid_tosca_yaml_err_msg = (
+                _('The file "%(template)s" in the CSAR "%(csar)s" does not '
+                  'contain valid TOSCA YAML content.') %
+                {'template': main_template, 'csar': self.path})
+            try:
+                tosca_yaml = yaml.load(data)
+                if type(tosca_yaml) is not dict:
+                    ExceptionCollector.appendException(
+                        ValidationError(message=invalid_tosca_yaml_err_msg))
+                return tosca_yaml
+            except Exception:
+                ExceptionCollector.appendException(
+                    ValidationError(message=invalid_tosca_yaml_err_msg))
+
+    def get_description(self):
+        desc = self._get_metadata('Description')
+        if desc is not None:
+            return desc
+
+        self.metadata['Description'] = \
+            self.get_main_template_yaml().get('description')
+        return self.metadata['Description']
+
+    def decompress(self):
+        if not self.is_validated:
+            self.validate()
+        self.temp_dir = tempfile.NamedTemporaryFile().name
+        with zipfile.ZipFile(self.csar, "r") as zf:
+            zf.extractall(self.temp_dir)
+
+    def _validate_external_references(self):
+        """Extracts files referenced in the main template
+
+        These references are currently supported:
+        * imports
+        * interface implementations
+        * artifacts
+        """
+        try:
+            self.decompress()
+            main_tpl_file = self.get_main_template()
+            if not main_tpl_file:
+                return
+            main_tpl = self.get_main_template_yaml()
+
+            if 'imports' in main_tpl:
+                ImportsLoader(main_tpl['imports'],
+                              os.path.join(self.temp_dir, main_tpl_file))
+
+            if 'topology_template' in main_tpl:
+                topology_template = main_tpl['topology_template']
+
+                if 'node_templates' in topology_template:
+                    node_templates = topology_template['node_templates']
+
+                    for node_template_key in node_templates:
+                        node_template = node_templates[node_template_key]
+                        if 'artifacts' in node_template:
+                            artifacts = node_template['artifacts']
+                            for artifact_key in artifacts:
+                                artifact = artifacts[artifact_key]
+                                if isinstance(artifact, six.string_types):
+                                    self._validate_external_reference(
+                                        main_tpl_file,
+                                        artifact)
+                                elif isinstance(artifact, dict):
+                                    if 'file' in artifact:
+                                        self._validate_external_reference(
+                                            main_tpl_file,
+                                            artifact['file'])
+                                else:
+                                    ExceptionCollector.appendException(
+                                        ValueError(_('Unexpected artifact '
+                                                     'definition for "%s".')
+                                                   % artifact_key))
+                                    self.error_caught = True
+                        if 'interfaces' in node_template:
+                            interfaces = node_template['interfaces']
+                            for interface_key in interfaces:
+                                interface = interfaces[interface_key]
+                                for opertation_key in interface:
+                                    operation = interface[opertation_key]
+                                    if isinstance(operation, six.string_types):
+                                        self._validate_external_reference(
+                                            main_tpl_file,
+                                            operation,
+                                            False)
+                                    elif isinstance(operation, dict):
+                                        if 'implementation' in operation:
+                                            self._validate_external_reference(
+                                                main_tpl_file,
+                                                operation['implementation'])
+        finally:
+            if self.temp_dir:
+                shutil.rmtree(self.temp_dir)
+
+    def _validate_external_reference(self, tpl_file, resource_file,
+                                     raise_exc=True):
+        """Verify that the external resource exists
+
+        If resource_file is a URL verify that the URL is valid.
+        If resource_file is a relative path verify that the path is valid
+        considering base folder (self.temp_dir) and tpl_file.
+        Note that in a CSAR resource_file cannot be an absolute path.
+        """
+        if UrlUtils.validate_url(resource_file):
+            msg = (_('The resource at "%s" cannot be accessed.') %
+                   resource_file)
+            try:
+                if UrlUtils.url_accessible(resource_file):
+                    return
+                else:
+                    ExceptionCollector.appendException(
+                        URLException(what=msg))
+                    self.error_caught = True
+            except Exception:
+                ExceptionCollector.appendException(
+                    URLException(what=msg))
+                self.error_caught = True
+
+        if os.path.isfile(os.path.join(self.temp_dir,
+                                       os.path.dirname(tpl_file),
+                                       resource_file)):
+            return
+
+        if raise_exc:
+            ExceptionCollector.appendException(
+                ValueError(_('The resource "%s" does not exist.')
+                           % resource_file))
+            self.error_caught = True
+*/
+
+
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/utils/CopyUtils.java b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/CopyUtils.java
new file mode 100644
index 0000000..db236e1
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/CopyUtils.java
@@ -0,0 +1,29 @@
+package org.openecomp.sdc.toscaparser.api.utils;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public class CopyUtils {
+
+    @SuppressWarnings("unchecked")
+	public static Object copyLhmOrAl(Object src) {
+    	if(src instanceof LinkedHashMap) {
+    		LinkedHashMap<String,Object> dst = new LinkedHashMap<String,Object>();
+    		for(Map.Entry<String,Object> me: ((LinkedHashMap<String,Object>)src).entrySet()) {
+    			dst.put(me.getKey(),me.getValue());	
+    		}
+    		return dst;
+    	}
+    	else if(src instanceof ArrayList) {
+    		ArrayList<Object> dst = new ArrayList<Object>();
+    		for(Object o: (ArrayList<Object>)src) {
+    			dst.add(o);
+    		}
+    		return dst;
+    	}
+    	else {
+    		return null;
+    	}
+    }
+}
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/utils/DumpUtils.java b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/DumpUtils.java
new file mode 100644
index 0000000..32c69cd
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/DumpUtils.java
@@ -0,0 +1,55 @@
+package org.openecomp.sdc.toscaparser.api.utils;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public class DumpUtils {
+	
+	@SuppressWarnings("unchecked")
+	public static void dumpYaml(Object yo,int level) {
+		final String indent = "                                                                         ";
+    	try {
+	    	if(yo == null) {
+	    		System.out.println("<null>");
+	    		return;
+	    	}
+			String cname = yo.getClass().getSimpleName();
+	    	System.out.print(cname);
+	    	if(cname.equals("LinkedHashMap")) {
+				LinkedHashMap<String,Object> lhm = (LinkedHashMap<String,Object>)yo;
+	    		System.out.println();
+				for(Map.Entry<String,Object> me: lhm.entrySet()) {
+					System.out.print(indent.substring(0,level) + me.getKey() + ": ");
+					dumpYaml(me.getValue(),level+2);
+				}
+	    	}
+	    	else if(cname.equals("ArrayList")) {
+	    		ArrayList<Object> al = (ArrayList<Object>)yo;
+	    		System.out.println();
+	    		for (int i=0; i<al.size(); i++) {
+	    			System.out.format("%s[%d] ",indent.substring(0,level),i);
+	    			dumpYaml(al.get(i),level+2);
+	    		}
+	    	}
+	    	else if(cname.equals("String")) {
+	    		System.out.println(" ==> \"" + (String)yo + "\"");
+	    	}
+	    	else if(cname.equals("Integer")) {
+	    		System.out.println(" ==> " + (int)yo);
+	    	}
+	    	else if(cname.equals("Boolean")) {
+	    		System.out.println(" ==> " + (boolean)yo);
+	    	}
+	    	else if(cname.equals("Double")) {
+	    		System.out.println(" ==> " + (double)yo);
+	    	}
+	    	else {
+	    		System.out.println(" !! unexpected type");
+	    	}
+    	}
+    	catch(Exception e) {
+    		System.out.println("Exception!! " + e.getMessage());	
+    	}
+	}
+}
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/utils/JToscaErrorCodes.java b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/JToscaErrorCodes.java
new file mode 100644
index 0000000..354fef0
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/JToscaErrorCodes.java
@@ -0,0 +1,32 @@
+package org.openecomp.sdc.toscaparser.api.utils;
+
+
+public enum JToscaErrorCodes {
+    MISSING_META_FILE("JT1001"),
+    INVALID_META_YAML_CONTENT("JT1002"),
+    ENTRY_DEFINITION_NOT_DEFINED("JT1003"),
+    MISSING_ENTRY_DEFINITION_FILE ("JT1004"),
+    GENERAL_ERROR("JT1005"),
+    PATH_NOT_VALID("JT1006"),
+    CSAR_TOSCA_VALIDATION_ERROR("JT1007"),
+    INVALID_CSAR_FORMAT("JT1008");
+
+    private String value;
+
+    private JToscaErrorCodes(String value) {
+        this.value = value;
+    }
+
+    public String getValue() {
+        return value;
+    }
+
+    public static JToscaErrorCodes getByCode(String code) {
+        for(JToscaErrorCodes v : values()){
+            if( v.getValue().equals(code)){
+                return v;
+            }
+        }
+        return null;
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/utils/TOSCAVersionProperty.java b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/TOSCAVersionProperty.java
new file mode 100644
index 0000000..6b3c1ce
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/TOSCAVersionProperty.java
@@ -0,0 +1,182 @@
+package org.openecomp.sdc.toscaparser.api.utils;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+
+public class TOSCAVersionProperty {// test with functions/test_concat.yaml
+	
+	private String version;
+	
+	private static final String versionRe =
+		    "^(?<gMajorVersion>([0-9][0-9]*))" +
+            "(\\.(?<gMinorVersion>([0-9][0-9]*)))?" +
+            "(\\.(?<gFixVersion>([0-9][0-9]*)))?" +
+            "(\\.(?<gQualifier>([0-9A-Za-z]+)))?" +
+            "(\\-(?<gBuildVersion>[0-9])*)?$";
+
+	private String minorVersion = null;
+	private String majorVersion = null;
+	private String fixVersion = null;
+	private String qualifier = null;
+	private String buildVersion = null;
+
+	
+	public TOSCAVersionProperty(Object _version) {
+		version = _version.toString();
+
+        if(version.equals("0") || version.equals("0.0") || version.equals("0.0.0")) {
+            //log.warning(_('Version assumed as not provided'))
+            version = "";
+            return;
+        }
+
+		Pattern pattern = Pattern.compile(versionRe);
+		Matcher matcher = pattern.matcher(version);
+		if(!matcher.find()) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+                "InvalidTOSCAVersionPropertyException: " +
+                "Value of TOSCA version property \"%s\" is invalid",
+                version));
+            return;
+		}
+        minorVersion = matcher.group("gMinorVersion");
+        majorVersion = matcher.group("gMajorVersion");
+        fixVersion = matcher.group("gFixVersion");
+        qualifier = _validateQualifier(matcher.group("gQualifier"));
+        buildVersion = _validateBuild(matcher.group("gBuildVersion"));
+        _validateMajorVersion(majorVersion);
+	
+	}
+	
+	private String _validateMajorVersion(String value) {
+        // Validate major version
+
+        // Checks if only major version is provided and assumes
+        // minor version as 0.
+        // Eg: If version = 18, then it returns version = '18.0'
+
+        if(minorVersion == null && buildVersion == null && !value.equals("0")) {
+            //log.warning(_('Minor version assumed "0".'))
+            version = version + "0";
+        }
+        return value;
+	}
+
+	private String _validateQualifier(String value) {
+	    // Validate qualifier
+	
+	    // TOSCA version is invalid if a qualifier is present without the
+	    // fix version or with all of major, minor and fix version 0s.
+	
+	    // For example, the following versions are invalid
+	    //    18.0.abc
+	    //    0.0.0.abc
+		
+		if((fixVersion == null && value != null) ||
+		   (minorVersion.equals("0") && majorVersion.equals("0") && 
+		      fixVersion.equals("0") &&  value != null)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "InvalidTOSCAVersionPropertyException: " +
+	                "Value of TOSCA version property \"%s\" is invalid",
+	                version));
+		}
+		return value;
+	}
+
+    private String _validateBuild(String value) {
+        // Validate build version
+
+        // TOSCA version is invalid if build version is present without the qualifier.
+        // Eg: version = 18.0.0-1 is invalid.
+
+    	if(qualifier == null && value != null) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+      	                "InvalidTOSCAVersionPropertyException: " +
+       	                "Value of TOSCA version property \"%s\" is invalid",
+       	                version));
+    	}
+        return value;
+    }
+
+	public Object getVersion() {
+		return version;
+	}
+
+}
+
+/*python
+
+class TOSCAVersionProperty(object):
+
+    VERSION_RE = re.compile('^(?P<major_version>([0-9][0-9]*))'
+                            '(\.(?P<minor_version>([0-9][0-9]*)))?'
+                            '(\.(?P<fix_version>([0-9][0-9]*)))?'
+                            '(\.(?P<qualifier>([0-9A-Za-z]+)))?'
+                            '(\-(?P<build_version>[0-9])*)?$')
+
+    def __init__(self, version):
+        self.version = str(version)
+        match = self.VERSION_RE.match(self.version)
+        if not match:
+            ExceptionCollector.appendException(
+                InvalidTOSCAVersionPropertyException(what=(self.version)))
+            return
+        ver = match.groupdict()
+        if self.version in ['0', '0.0', '0.0.0']:
+            log.warning(_('Version assumed as not provided'))
+            self.version = None
+        self.minor_version = ver['minor_version']
+        self.major_version = ver['major_version']
+        self.fix_version = ver['fix_version']
+        self.qualifier = self._validate_qualifier(ver['qualifier'])
+        self.build_version = self._validate_build(ver['build_version'])
+        self._validate_major_version(self.major_version)
+
+    def _validate_major_version(self, value):
+        """Validate major version
+
+        Checks if only major version is provided and assumes
+        minor version as 0.
+        Eg: If version = 18, then it returns version = '18.0'
+        """
+
+        if self.minor_version is None and self.build_version is None and \
+                value != '0':
+            log.warning(_('Minor version assumed "0".'))
+            self.version = '.'.join([value, '0'])
+        return value
+
+    def _validate_qualifier(self, value):
+        """Validate qualifier
+
+           TOSCA version is invalid if a qualifier is present without the
+           fix version or with all of major, minor and fix version 0s.
+
+           For example, the following versions are invalid
+              18.0.abc
+              0.0.0.abc
+        """
+        if (self.fix_version is None and value) or \
+            (self.minor_version == self.major_version ==
+             self.fix_version == '0' and value):
+            ExceptionCollector.appendException(
+                InvalidTOSCAVersionPropertyException(what=(self.version)))
+        return value
+
+    def _validate_build(self, value):
+        """Validate build version
+
+           TOSCA version is invalid if build version is present without the
+           qualifier.
+           Eg: version = 18.0.0-1 is invalid.
+        """
+        if not self.qualifier and value:
+            ExceptionCollector.appendException(
+                InvalidTOSCAVersionPropertyException(what=(self.version)))
+        return value
+
+    def get_version(self):
+        return self.version
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/utils/ThreadLocalsHolder.java b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/ThreadLocalsHolder.java
new file mode 100644
index 0000000..47ba972
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/ThreadLocalsHolder.java
@@ -0,0 +1,24 @@
+package org.openecomp.sdc.toscaparser.api.utils;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+
+public class ThreadLocalsHolder {
+
+    private static final ThreadLocal<ExceptionCollector> exceptionCollectorThreadLocal = new ThreadLocal<>();
+
+    private ThreadLocalsHolder(){}
+
+    public static ExceptionCollector getCollector() {
+        return exceptionCollectorThreadLocal.get();
+    }
+
+    public static void setCollector(ExceptionCollector exceptionCollector) {
+        cleanup();
+        exceptionCollectorThreadLocal.set(exceptionCollector);
+    }
+
+    public static void cleanup(){
+        exceptionCollectorThreadLocal.remove();
+    }
+
+}
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/utils/UrlUtils.java b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/UrlUtils.java
new file mode 100644
index 0000000..092f827
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/UrlUtils.java
@@ -0,0 +1,123 @@
+package org.openecomp.sdc.toscaparser.api.utils;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
+import java.net.URL;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+
+public class UrlUtils {
+	
+	public static boolean validateUrl(String sUrl) {
+        // Validates whether the given path is a URL or not
+
+        // If the given path includes a scheme (http, https, ftp, ...) and a net
+        // location (a domain name such as www.github.com) it is validated as a URL
+		try {
+			URL url = new URL(sUrl);
+			if(url.getProtocol().equals("file")) {
+				return true;
+			}
+			return url.getAuthority() != null;
+		}
+		catch(MalformedURLException e) {
+			return false; 
+		}
+	}
+	
+	public static String joinUrl(String sUrl,String relativePath) {
+        // Builds a new URL from the given URL and the relative path
+
+        // Example:
+        //   url: http://www.githib.com/openstack/heat
+        //   relative_path: heat-translator
+        //   - joined: http://www.githib.com/openstack/heat-translator
+		if(!validateUrl(sUrl)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+					"ValueError: The URL \"%s\" is malformed",sUrl));
+		}
+		try {
+			URL base = new URL(sUrl);
+			return (new URL(base,relativePath)).toString();
+		}
+		catch(MalformedURLException e) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+					"ValueError: Joining URL \"%s\" and relative path \"%s\" caused an exception",sUrl,relativePath));
+			return sUrl; 
+		}
+	}
+
+	public static boolean isUrlAccessible(String sUrl) {
+        // Validates whether the given URL is accessible
+
+        // Returns true if the get call returns a 200 response code.
+        // Otherwise, returns false.
+		try {
+			HttpURLConnection connection = (HttpURLConnection) new URL(sUrl).openConnection();
+			connection.setRequestMethod("HEAD");
+			int responseCode = connection.getResponseCode();
+			return responseCode == 200;
+		}
+		catch(IOException e) {
+			return false;
+		}
+	}
+
+}
+
+/*python
+
+from six.moves.urllib.parse import urljoin
+from six.moves.urllib.parse import urlparse
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.utils.gettextutils import _
+
+try:
+    # Python 3.x
+    import urllib.request as urllib2
+except ImportError:
+    # Python 2.x
+    import urllib2
+
+
+class UrlUtils(object):
+
+    @staticmethod
+    def validate_url(path):
+        """Validates whether the given path is a URL or not.
+
+        If the given path includes a scheme (http, https, ftp, ...) and a net
+        location (a domain name such as www.github.com) it is validated as a
+        URL.
+        """
+        parsed = urlparse(path)
+        if parsed.scheme == 'file':
+            # If the url uses the file scheme netloc will be ""
+            return True
+        else:
+            return bool(parsed.scheme) and bool(parsed.netloc)
+
+    @staticmethod
+    def join_url(url, relative_path):
+        """Builds a new URL from the given URL and the relative path.
+
+        Example:
+          url: http://www.githib.com/openstack/heat
+          relative_path: heat-translator
+          - joined: http://www.githib.com/openstack/heat-translator
+        """
+        if not UrlUtils.validate_url(url):
+            ExceptionCollector.appendException(
+                ValueError(_('"%s" is not a valid URL.') % url))
+        return urljoin(url, relative_path)
+
+    @staticmethod
+    def url_accessible(url):
+        """Validates whether the given URL is accessible.
+
+        Returns true if the get call returns a 200 response code.
+        Otherwise, returns false.
+        """
+        return urllib2.urlopen(url).getcode() == 200
+*/
\ No newline at end of file
diff --git a/src/main/java/org/openecomp/sdc/toscaparser/api/utils/ValidateUtils.java b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/ValidateUtils.java
new file mode 100644
index 0000000..291316f
--- /dev/null
+++ b/src/main/java/org/openecomp/sdc/toscaparser/api/utils/ValidateUtils.java
@@ -0,0 +1,409 @@
+package org.openecomp.sdc.toscaparser.api.utils;
+
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.LinkedHashMap;
+
+import org.openecomp.sdc.toscaparser.api.common.ExceptionCollector;
+
+public class ValidateUtils {
+	
+	private static final String RANGE_UNBOUNDED = "UNBOUNDED";
+
+	public static Object strToNum(Object value) {
+	    // Convert a string representation of a number into a numeric type
+	    // tODO(TBD) we should not allow numeric values in, input should be str
+		if(value instanceof Number) {
+			return value;
+		}
+		if(!(value instanceof String)) {
+			
+		}
+		try {
+			return Integer.parseInt((String)value);
+		}
+		catch(NumberFormatException e) {
+		}
+		try {
+			return Float.parseFloat((String)value);
+		}
+		catch(Exception e) {
+		}
+		return null;
+	}
+	
+	public static Object validateNumeric(Object value) {
+		if(!(value instanceof Number)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+		            "ValueError: \"%s\" is not a numeric",value.toString()));
+		}
+		return value;
+	}
+
+	public static Object validateInteger(Object value) {
+		if(!(value instanceof Integer)) {
+			// allow "true" and "false"
+			if(value instanceof Boolean) {
+				return (Boolean)value ? 1 : 0;
+			}
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "ValueError: \"%s\" is not an integer",value.toString()));
+		}
+	    return value;
+	}
+
+	public static Object validateFloat(Object value) {
+		if(!(value instanceof Float || value instanceof Double)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "ValueError: \"%s\" is not a float",value.toString()));
+		}
+	    return value;
+	}
+
+	public static Object validateString(Object value) {
+		if(!(value instanceof String)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "ValueError: \'%s\' is not a string",value.toString()));
+		}
+	    return value;
+	}
+
+	public static Object validateList(Object value) {
+		if(!(value instanceof ArrayList)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "ValueError: \"%s\" is not a list",value.toString()));
+		}
+	    return value;
+	}
+
+	
+	@SuppressWarnings("unchecked")
+	public static Object validateRange(Object range) {
+	    // list class check
+	    validateList(range);
+	    // validate range list has a min and max
+	    if(range instanceof ArrayList && ((ArrayList<Object>)range).size() != 2) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "ValueError: \"%s\" is not a valid range",range.toString()));
+	        // too dangerous to continue...
+	        return range;
+	    }
+	    // validate min and max are numerics or the keyword UNBOUNDED
+	    boolean minTest = false;
+	    boolean maxTest = false;
+	    Object r0 = ((ArrayList<Object>)range).get(0);
+	    Object r1 = ((ArrayList<Object>)range).get(1);
+	    
+	    if(!(r0 instanceof Integer) && !(r0 instanceof Float) ||
+	       !(r1 instanceof Integer) && !(r1 instanceof Float)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+		            "ValueError: \"%s\" is not a valid range",range.toString()));
+		        // too dangerous to continue...
+	        return range;
+	    }
+		
+	    Float min = 0.0F;
+	    Float max = 0.0F;
+	    if(r0 instanceof String && ((String)r0).equals(RANGE_UNBOUNDED)) {
+	    	minTest = true;
+	    }
+	    else {
+	    	min = r0 instanceof Integer ? ((Integer)r0).floatValue() : (Float)r0;
+	    }
+	    if(r1 instanceof String && ((String)r1).equals(RANGE_UNBOUNDED)) {
+	    	maxTest = true;
+	    }
+	    else {
+	    	max = r1 instanceof Integer ? ((Integer)r1).floatValue() : (Float)r1;
+	    }
+	    
+	    // validate the max > min (account for UNBOUNDED)
+	    if(!minTest && !maxTest) {
+	        // Note: min == max is allowed
+	        if(min > max) {
+				ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "ValueError:\"%s\" is not a valid range",range.toString()));
+	        }
+	    }
+	    return range;
+	}
+
+	@SuppressWarnings("unchecked")
+	public static Object validateValueInRange(Object value,Object range,String propName) {
+		// verify all 3 are numeric and convert to Floats
+		if(!(value instanceof Integer || value instanceof Float)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "ValueError: validateInRange: \"%s\" is not a number",range.toString()));
+            return value;
+	    }
+		Float fval = value instanceof Integer ? ((Integer)value).floatValue() : (Float)value;
+		
+		//////////////////////////
+	    //"validateRange(range);"
+		//////////////////////////
+	    // better safe than sorry...
+	    // validate that range list has a min and max
+	    if(range instanceof ArrayList && ((ArrayList<Object>)range).size() != 2) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "ValueError: \"%s\" is not a valid range",range.toString()));
+	        // too dangerous to continue...
+	        return value;
+	    }
+	    // validate min and max are numerics or the keyword UNBOUNDED
+	    boolean minTest = false;
+	    boolean maxTest = false;
+	    Object r0 = ((ArrayList<Object>)range).get(0);
+	    Object r1 = ((ArrayList<Object>)range).get(1);
+	    
+	    if(!(r0 instanceof Integer) && !(r0 instanceof Float) ||
+	       !(r1 instanceof Integer) && !(r1 instanceof Float)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+		            "ValueError: \"%s\" is not a valid range",range.toString()));
+		        // too dangerous to continue...
+	        return value;
+	    }
+		
+	    Float min = 0.0F;
+	    Float max = 0.0F;
+	    if(r0 instanceof String && ((String)r0).equals(RANGE_UNBOUNDED)) {
+	    	minTest = true;
+	    }
+	    else {
+	    	min = r0 instanceof Integer ? ((Integer)r0).floatValue() : (Float)r0;
+	    }
+	    if(r1 instanceof String && ((String)r1).equals(RANGE_UNBOUNDED)) {
+	    	maxTest = true;
+	    }
+	    else {
+	    	max = r1 instanceof Integer ? ((Integer)r1).floatValue() : (Float)r1;
+	    }
+	    
+	    // validate the max > min (account for UNBOUNDED)
+	    if(!minTest && !maxTest) {
+	        // Note: min == max is allowed
+	        if(min > max) {
+				ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "ValueError:\"%s\" is not a valid range",range.toString()));
+	        }
+	    }
+	    // finally...
+	    boolean bError = false;
+	    //Note: value is valid if equal to min
+	    if(!minTest) {
+	        if(fval < min) {
+	        	bError = true;
+	        }
+	    }
+	    // Note: value is valid if equal to max
+	    if(!maxTest) {
+	        if(fval > max) {
+	        	bError = true;
+	        }
+	    }
+	    if(bError) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	                "RangeValueError: Property \"%s\", \"%s\" not in range [\"%s\" - \"%s\"",
+	                propName,value.toString(),r0.toString(),r1.toString()));
+	    }
+	    return value;
+	}
+	
+	public static Object validateMap(Object ob) {
+		if(!(ob instanceof LinkedHashMap)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+	            "ValueError\"%s\" is not a map.",ob.toString()));
+		}
+	    return ob;
+	}
+
+	public static Object validateBoolean(Object value) {
+		if(value instanceof Boolean) { 
+			return value;
+		}
+		if(value instanceof String) {  
+			String normalized = ((String)value).toLowerCase();
+			if(normalized.equals("true") || normalized.equals("false")) {
+				return normalized.equals("true");
+			}
+		}
+		ThreadLocalsHolder.getCollector().appendException(String.format(
+		        "ValueError: \"%s\" is not a boolean",value.toString()));
+	    return value;
+	}
+
+	public static Object validateTimestamp(Object value) {
+		/*
+	    try:
+	        # Note: we must return our own exception message
+	        # as dateutil's parser returns different types / values on
+	        # different systems. OSX, for example, returns a tuple
+	        # containing a different error message than Linux
+	        dateutil.parser.parse(value)
+	    except Exception as e:
+	        original_err_msg = str(e)
+	        log.error(original_err_msg)
+	        ExceptionCollector.appendException(
+	            ValueError(_('"%(val)s" is not a valid timestamp. "%(msg)s"') %
+	                       {'val': value, 'msg': original_err_msg}))
+		*/
+		
+		// timestamps are loaded as Date objects by the YAML parser
+		if(!(value instanceof Date)) {
+			ThreadLocalsHolder.getCollector().appendException(String.format(
+		        "ValueError: \"%s\" is not a valid timestamp",
+		        value.toString()));
+			
+		}
+		return value;
+	}
+	
+}
+
+/*python
+
+from toscaparser.elements import constraints
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidTOSCAVersionPropertyException
+from toscaparser.common.exception import RangeValueError
+from toscaparser.utils.gettextutils import _
+
+log = logging.getLogger('tosca')
+
+RANGE_UNBOUNDED = 'UNBOUNDED'
+
+
+def str_to_num(value):
+    '''Convert a string representation of a number into a numeric type.'''
+    # tODO(TBD) we should not allow numeric values in, input should be str
+    if isinstance(value, numbers.Number):
+        return value
+    try:
+        return int(value)
+    except ValueError:
+        return float(value)
+
+
+def validate_numeric(value):
+    if not isinstance(value, numbers.Number):
+        ExceptionCollector.appendException(
+            ValueError(_('"%s" is not a numeric.') % value))
+    return value
+
+
+def validate_integer(value):
+    if not isinstance(value, int):
+        try:
+            value = int(value)
+        except Exception:
+            ExceptionCollector.appendException(
+                ValueError(_('"%s" is not an integer.') % value))
+    return value
+
+
+def validate_float(value):
+    if not isinstance(value, float):
+        ExceptionCollector.appendException(
+            ValueError(_('"%s" is not a float.') % value))
+    return value
+
+
+def validate_string(value):
+    if not isinstance(value, six.string_types):
+        ExceptionCollector.appendException(
+            ValueError(_('"%s" is not a string.') % value))
+    return value
+
+
+def validate_list(value):
+    if not isinstance(value, list):
+        ExceptionCollector.appendException(
+            ValueError(_('"%s" is not a list.') % value))
+    return value
+
+
+def validate_range(range):
+    # list class check
+    validate_list(range)
+    # validate range list has a min and max
+    if len(range) != 2:
+        ExceptionCollector.appendException(
+            ValueError(_('"%s" is not a valid range.') % range))
+    # validate min and max are numerics or the keyword UNBOUNDED
+    min_test = max_test = False
+    if not range[0] == RANGE_UNBOUNDED:
+        min = validate_numeric(range[0])
+    else:
+        min_test = True
+    if not range[1] == RANGE_UNBOUNDED:
+        max = validate_numeric(range[1])
+    else:
+        max_test = True
+    # validate the max > min (account for UNBOUNDED)
+    if not min_test and not max_test:
+        # Note: min == max is allowed
+        if min > max:
+            ExceptionCollector.appendException(
+                ValueError(_('"%s" is not a valid range.') % range))
+
+    return range
+
+
+def validate_value_in_range(value, range, prop_name):
+    validate_numeric(value)
+    validate_range(range)
+
+    # Note: value is valid if equal to min
+    if range[0] != RANGE_UNBOUNDED:
+        if value < range[0]:
+            ExceptionCollector.appendException(
+                RangeValueError(pname=prop_name,
+                                pvalue=value,
+                                vmin=range[0],
+                                vmax=range[1]))
+    # Note: value is valid if equal to max
+    if range[1] != RANGE_UNBOUNDED:
+        if value > range[1]:
+            ExceptionCollector.appendException(
+                RangeValueError(pname=prop_name,
+                                pvalue=value,
+                                vmin=range[0],
+                                vmax=range[1]))
+    return value
+
+
+def validate_map(value):
+    if not isinstance(value, collections.Mapping):
+        ExceptionCollector.appendException(
+            ValueError(_('"%s" is not a map.') % value))
+    return value
+
+
+def validate_boolean(value):
+    if isinstance(value, bool):
+        return value
+
+    if isinstance(value, str):
+        normalised = value.lower()
+        if normalised in ['true', 'false']:
+            return normalised == 'true'
+
+    ExceptionCollector.appendException(
+        ValueError(_('"%s" is not a boolean.') % value))
+
+
+def validate_timestamp(value):
+    try:
+        # Note: we must return our own exception message
+        # as dateutil's parser returns different types / values on
+        # different systems. OSX, for example, returns a tuple
+        # containing a different error message than Linux
+        dateutil.parser.parse(value)
+    except Exception as e:
+        original_err_msg = str(e)
+        log.error(original_err_msg)
+        ExceptionCollector.appendException(
+            ValueError(_('"%(val)s" is not a valid timestamp. "%(msg)s"') %
+                       {'val': value, 'msg': original_err_msg}))
+    return
+
+*/
\ No newline at end of file
diff --git a/src/main/resources/TOSCA_definition_1_0.yaml b/src/main/resources/TOSCA_definition_1_0.yaml
new file mode 100644
index 0000000..554b7b6
--- /dev/null
+++ b/src/main/resources/TOSCA_definition_1_0.yaml
@@ -0,0 +1,967 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+##########################################################################
+# The content of this file reflects TOSCA Simple Profile in YAML version
+# 1.0.0. It describes the definition for TOSCA types including Node Type,
+# Relationship Type, Capability Type and Interfaces.
+##########################################################################
+tosca_definitions_version: tosca_simple_yaml_1_0
+
+##########################################################################
+# Node Type.
+# A Node Type is a reusable entity that defines the type of one or more
+# Node Templates.
+##########################################################################
+node_types:
+  tosca.nodes.Root:
+    description: >
+      The TOSCA root node all other TOSCA base node types derive from.
+    attributes:
+      tosca_id:
+        type: string
+      tosca_name:
+        type: string
+      state:
+        type: string
+    capabilities:
+      feature:
+        type: tosca.capabilities.Node
+    requirements:
+      - dependency:
+          capability: tosca.capabilities.Node
+          node: tosca.nodes.Root
+          relationship: tosca.relationships.DependsOn
+          occurrences: [ 0, UNBOUNDED ]
+    interfaces:
+      Standard:
+        type: tosca.interfaces.node.lifecycle.Standard
+
+  tosca.nodes.Compute:
+    derived_from: tosca.nodes.Root
+    attributes:
+      private_address:
+        type: string
+      public_address:
+        type: string
+      networks:
+        type: map
+        entry_schema:
+          type: tosca.datatypes.network.NetworkInfo
+      ports:
+        type: map
+        entry_schema:
+          type: tosca.datatypes.network.PortInfo
+    capabilities:
+        host:
+           type: tosca.capabilities.Container
+        binding:
+           type: tosca.capabilities.network.Bindable
+        os:
+           type: tosca.capabilities.OperatingSystem
+        scalable:
+           type: tosca.capabilities.Scalable
+        endpoint:
+           type: tosca.capabilities.Endpoint.Admin
+    requirements:
+      - local_storage:
+          capability: tosca.capabilities.Attachment
+          node: tosca.nodes.BlockStorage
+          relationship: tosca.relationships.AttachesTo
+          occurrences: [0, UNBOUNDED]
+
+  tosca.nodes.SoftwareComponent:
+    derived_from: tosca.nodes.Root
+    properties:
+      # domain-specific software component version
+      component_version:
+        type: version
+        required: false
+        description: >
+          Software component version.
+      admin_credential:
+        type: tosca.datatypes.Credential
+        required: false
+    requirements:
+      - host:
+          capability: tosca.capabilities.Container
+          node: tosca.nodes.Compute
+          relationship: tosca.relationships.HostedOn
+
+  tosca.nodes.DBMS:
+    derived_from: tosca.nodes.SoftwareComponent
+    properties:
+      port:
+        required: false
+        type: integer
+        description: >
+          The port the DBMS service will listen to for data and requests.
+      root_password:
+        required: false
+        type: string
+        description: >
+          The root password for the DBMS service.
+    capabilities:
+      host:
+        type: tosca.capabilities.Container
+        valid_source_types: [tosca.nodes.Database]
+
+  tosca.nodes.Database:
+    derived_from: tosca.nodes.Root
+    properties:
+      user:
+        required: false
+        type: string
+        description: >
+          User account name for DB administration
+      port:
+        required: false
+        type: integer
+        description:  >
+          The port the database service will use to listen for incoming data and
+          requests.
+      name:
+        required: false
+        type: string
+        description: >
+          The name of the database.
+      password:
+        required: false
+        type: string
+        description: >
+          The password for the DB user account
+    requirements:
+      - host:
+          capability: tosca.capabilities.Container
+          node: tosca.nodes.DBMS
+          relationship: tosca.relationships.HostedOn
+    capabilities:
+      database_endpoint:
+        type: tosca.capabilities.Endpoint.Database
+
+  tosca.nodes.WebServer:
+    derived_from: tosca.nodes.SoftwareComponent
+    capabilities:
+      data_endpoint:
+        type: tosca.capabilities.Endpoint
+      admin_endpoint:
+        type: tosca.capabilities.Endpoint.Admin
+      host:
+        type: tosca.capabilities.Container
+        valid_source_types: [tosca.nodes.WebApplication]
+
+  tosca.nodes.WebApplication:
+    derived_from: tosca.nodes.Root
+    properties:
+      context_root:
+        type: string
+        required: false
+    requirements:
+      - host:
+          capability: tosca.capabilities.Container
+          node: tosca.nodes.WebServer
+          relationship: tosca.relationships.HostedOn
+    capabilities:
+      app_endpoint:
+        type: tosca.capabilities.Endpoint
+
+  tosca.nodes.BlockStorage:
+    derived_from: tosca.nodes.Root
+    properties:
+      size:
+        type: scalar-unit.size
+        constraints:
+          - greater_or_equal: 1 MB
+      volume_id:
+        type: string
+        required: false
+      snapshot_id:
+        type: string
+        required: false
+    attributes:
+      volume_id:
+        type: string
+    capabilities:
+      attachment:
+        type: tosca.capabilities.Attachment
+
+  tosca.nodes.network.Network:
+    derived_from: tosca.nodes.Root
+    description: >
+      The TOSCA Network node represents a simple, logical network service.
+    properties:
+      ip_version:
+        type: integer
+        required: false
+        default: 4
+        constraints:
+          - valid_values: [ 4, 6 ]
+        description: >
+          The IP version of the requested network. Valid values are 4 for ipv4
+          or 6 for ipv6.
+      cidr:
+        type: string
+        required: false
+        description: >
+          The cidr block of the requested network.
+      start_ip:
+        type: string
+        required: false
+        description: >
+           The IP address to be used as the start of a pool of addresses within
+           the full IP range derived from the cidr block.
+      end_ip:
+        type: string
+        required: false
+        description: >
+            The IP address to be used as the end of a pool of addresses within
+            the full IP range derived from the cidr block.
+      gateway_ip:
+        type: string
+        required: false
+        description: >
+           The gateway IP address.
+      network_name:
+        type: string
+        required: false
+        description: >
+           An identifier that represents an existing Network instance in the
+           underlying cloud infrastructure or can be used as the name of the
+           newly created network. If network_name is provided and no other
+           properties are provided (with exception of network_id), then an
+           existing network instance will be used. If network_name is provided
+           alongside with more properties then a new network with this name will
+           be created.
+      network_id:
+        type: string
+        required: false
+        description: >
+           An identifier that represents an existing Network instance in the
+           underlying cloud infrastructure. This property is mutually exclusive
+           with all other properties except network_name. This can be used alone
+           or together with network_name to identify an existing network.
+      segmentation_id:
+        type: string
+        required: false
+        description: >
+           A segmentation identifier in the underlying cloud infrastructure.
+           E.g. VLAN ID, GRE tunnel ID, etc..
+      network_type:
+        type: string
+        required: false
+        description: >
+           It specifies the nature of the physical network in the underlying
+           cloud infrastructure. Examples are flat, vlan, gre or vxlan.
+           For flat and vlan types, physical_network should be provided too.
+      physical_network:
+        type: string
+        required: false
+        description: >
+           It identifies the physical network on top of which the network is
+           implemented, e.g. physnet1. This property is required if network_type
+           is flat or vlan.
+      dhcp_enabled:
+        type: boolean
+        required: false
+        default: true
+        description: >
+          Indicates should DHCP service be enabled on the network or not.
+    capabilities:
+      link:
+        type: tosca.capabilities.network.Linkable
+    
+  tosca.nodes.network.Port:
+    derived_from: tosca.nodes.Root
+    description: >
+      The TOSCA Port node represents a logical entity that associates between
+      Compute and Network normative types. The Port node type effectively
+      represents a single virtual NIC on the Compute node instance.
+    properties:
+      ip_address:
+        type: string
+        required: false
+        description: >
+          Allow the user to set a static IP.
+      order:
+        type: integer
+        required: false
+        default: 0
+        constraints:
+          - greater_or_equal: 0
+        description: >
+          The order of the NIC on the compute instance (e.g. eth2).
+      is_default:
+        type: boolean
+        required: false
+        default: false
+        description: >
+          If is_default=true this port will be used for the default gateway
+          route. Only one port that is associated to single compute node can
+          set as is_default=true.
+      ip_range_start:
+        type: string
+        required: false
+        description: >
+          Defines the starting IP of a range to be allocated for the compute
+          instances that are associated with this Port.
+      ip_range_end:
+        type: string
+        required: false
+        description: >
+          Defines the ending IP of a range to be allocated for the compute
+          instances that are associated with this Port.
+    attributes:
+      ip_address:
+        type: string
+    requirements:
+      - binding:
+          description: >
+            Binding requirement expresses the relationship between Port and
+            Compute nodes. Effectively it indicates that the Port will be
+            attached to specific Compute node instance
+          capability: tosca.capabilities.network.Bindable
+          relationship: tosca.relationships.network.BindsTo
+          node: tosca.nodes.Compute
+      - link:
+          description: >
+            Link requirement expresses the relationship between Port and Network
+            nodes. It indicates which network this port will connect to.
+          capability: tosca.capabilities.network.Linkable
+          relationship: tosca.relationships.network.LinksTo
+          node: tosca.nodes.network.Network
+
+  tosca.nodes.network.FloatingIP:
+    derived_from: tosca.nodes.Root
+    description: >
+      The TOSCA FloatingIP node represents a floating IP that can associate to a Port.
+    properties:
+      floating_network:
+        type: string
+        required: true
+      floating_ip_address:
+        type: string
+        required: false
+      port_id:
+        type: string
+        required: false
+    requirements:
+      - link:
+          capability: tosca.capabilities.network.Linkable
+          relationship: tosca.relationships.network.LinksTo
+          node: tosca.nodes.network.Port
+
+  tosca.nodes.ObjectStorage:
+    derived_from: tosca.nodes.Root
+    description: >
+      The TOSCA ObjectStorage node represents storage that provides the ability
+      to store data as objects (or BLOBs of data) without consideration for the
+      underlying filesystem or devices
+    properties:
+      name:
+        type: string
+        required: true
+        description: >
+          The logical name of the object store (or container).
+      size:
+        type: scalar-unit.size
+        required: false
+        constraints:
+          - greater_or_equal: 0 GB
+        description: >
+          The requested initial storage size.
+      maxsize:
+        type: scalar-unit.size
+        required: false
+        constraints:
+          - greater_or_equal: 0 GB
+        description: >
+          The requested maximum storage size.
+    capabilities:
+      storage_endpoint:
+        type: tosca.capabilities.Endpoint
+
+  tosca.nodes.LoadBalancer:
+    derived_from: tosca.nodes.Root
+    properties:
+      algorithm:
+        type: string
+        required: false
+        status: experimental
+    capabilities:
+      client:
+        type: tosca.capabilities.Endpoint.Public
+        occurrences: [0, UNBOUNDED]
+        description: the Floating (IP) client’s on the public network can connect to
+    requirements:
+      - application:
+          capability: tosca.capabilities.Endpoint
+          relationship: tosca.relationships.RoutesTo
+          occurrences: [0, UNBOUNDED]
+          description: Connection to one or more load balanced applications
+
+  tosca.nodes.Container.Application:
+    derived_from: tosca.nodes.Root
+    requirements:
+      - host:
+          capability: tosca.capabilities.Container
+          node: tosca.nodes.Container.Runtime
+          relationship: tosca.relationships.HostedOn
+
+  tosca.nodes.Container.Runtime:
+    derived_from: tosca.nodes.SoftwareComponent
+    capabilities:
+      host:
+        type: tosca.capabilities.Container
+      scalable:
+        type: tosca.capabilities.Scalable
+
+  tosca.nodes.Container.Application.Docker:
+    derived_from: tosca.nodes.Container.Application
+    requirements:
+      - host:
+          capability: tosca.capabilities.Container.Docker
+
+##########################################################################
+# Relationship Type.
+# A Relationship Type is a reusable entity that defines the type of one
+# or more relationships between Node Types or Node Templates.
+##########################################################################
+relationship_types:
+  tosca.relationships.Root:
+    description: >
+      The TOSCA root Relationship Type all other TOSCA base Relationship Types
+      derive from.
+    attributes:
+      tosca_id:
+        type: string
+      tosca_name:
+        type: string
+    interfaces:
+      Configure:
+        type: tosca.interfaces.relationship.Configure
+
+  tosca.relationships.DependsOn:
+    derived_from: tosca.relationships.Root
+
+  tosca.relationships.HostedOn:
+    derived_from: tosca.relationships.Root
+    valid_target_types: [ tosca.capabilities.Container ]
+
+  tosca.relationships.ConnectsTo:
+    derived_from: tosca.relationships.Root
+    valid_target_types: [ tosca.capabilities.Endpoint ]
+    credential:
+      type: tosca.datatypes.Credential
+      required: false
+
+  tosca.relationships.AttachesTo:
+    derived_from: tosca.relationships.Root
+    valid_target_types: [ tosca.capabilities.Attachment ]
+    properties:
+      location:
+        required: true
+        type: string
+        constraints:
+          - min_length: 1
+      device:
+        required: false
+        type: string
+
+  tosca.relationships.RoutesTo:
+    derived_from: tosca.relationships.ConnectsTo
+    valid_target_types: [ tosca.capabilities.Endpoint ]
+
+  tosca.relationships.network.LinksTo:
+    derived_from: tosca.relationships.DependsOn
+    valid_target_types: [ tosca.capabilities.network.Linkable ]
+
+  tosca.relationships.network.BindsTo:
+    derived_from: tosca.relationships.DependsOn
+    valid_target_types: [ tosca.capabilities.network.Bindable ]
+
+##########################################################################
+# Capability Type.
+# A Capability Type is a reusable entity that describes a kind of
+# capability that a Node Type can declare to expose.
+##########################################################################
+capability_types:
+  tosca.capabilities.Root:
+    description: >
+      The TOSCA root Capability Type all other TOSCA base Capability Types
+      derive from.
+
+  tosca.capabilities.Node:
+    derived_from: tosca.capabilities.Root
+
+  tosca.capabilities.Container:
+    derived_from: tosca.capabilities.Root
+    properties:
+      num_cpus:
+        required: false
+        type: integer
+        constraints:
+          - greater_or_equal: 1
+      cpu_frequency:
+        required: false
+        type: scalar-unit.frequency
+        constraints:
+          - greater_or_equal: 0.1 GHz
+      disk_size:
+        required: false
+        type: scalar-unit.size
+        constraints:
+          - greater_or_equal: 0 MB
+      mem_size:
+        required: false
+        type: scalar-unit.size
+        constraints:
+          - greater_or_equal: 0 MB
+
+  tosca.capabilities.Endpoint:
+    derived_from: tosca.capabilities.Root
+    properties:
+      protocol:
+        type: string
+        required: true
+        default: tcp
+      port:
+        type: tosca.datatypes.network.PortDef
+        required: false
+      secure:
+        type: boolean
+        required: false
+        default: false
+      url_path:
+        type: string
+        required: false
+      port_name:
+        type: string
+        required: false
+      network_name:
+        type: string
+        required: false
+        default: PRIVATE
+      initiator:
+        type: string
+        required: false
+        default: source
+        constraints:
+          - valid_values: [source, target, peer]
+      ports:
+        type: map
+        required: false
+        constraints:
+          - min_length: 1
+        entry_schema:
+          type: tosca.datatypes.network.PortSpec
+    attributes:
+      ip_address:
+        type: string
+
+  tosca.capabilities.Endpoint.Admin:
+    derived_from: tosca.capabilities.Endpoint
+    properties:
+      secure:
+        type: boolean
+        default: true
+        constraints:
+          - equal: true
+
+  tosca.capabilities.Endpoint.Public:
+    derived_from: tosca.capabilities.Endpoint
+    properties:
+      # Change the default network_name to use the first public network found
+      network_name:
+        type: string
+        default: PUBLIC
+        constraints:
+          - equal: PUBLIC
+      floating:
+        description: >
+          Indicates that the public address should be allocated from a pool of
+          floating IPs that are associated with the network.
+        type: boolean
+        default: false
+        status: experimental
+      dns_name:
+        description: The optional name to register with DNS
+        type: string
+        required: false
+        status: experimental
+
+  tosca.capabilities.Scalable:
+    derived_from: tosca.capabilities.Root
+    properties:
+      min_instances:
+        type: integer
+        required: true
+        default: 1
+        description: >
+          This property is used to indicate the minimum number of instances
+          that should be created for the associated TOSCA Node Template by
+          a TOSCA orchestrator.
+      max_instances:
+        type: integer
+        required: true
+        default: 1
+        description: >
+          This property is used to indicate the maximum number of instances
+          that should be created for the associated TOSCA Node Template by
+          a TOSCA orchestrator.
+      default_instances:
+        type: integer
+        required: false
+        description: >
+          An optional property that indicates the requested default number
+          of instances that should be the starting number of instances a
+          TOSCA orchestrator should attempt to allocate.
+          The value for this property MUST be in the range between the values
+          set for min_instances and max_instances properties.
+
+  tosca.capabilities.Endpoint.Database:
+    derived_from: tosca.capabilities.Endpoint
+
+  tosca.capabilities.Attachment:
+    derived_from: tosca.capabilities.Root
+
+  tosca.capabilities.network.Linkable:
+    derived_from: tosca.capabilities.Root
+    description: >
+      A node type that includes the Linkable capability indicates that it can
+      be pointed by tosca.relationships.network.LinksTo relationship type, which
+      represents an association relationship between Port and Network node types.
+
+  tosca.capabilities.network.Bindable:
+    derived_from: tosca.capabilities.Root
+    description: >
+      A node type that includes the Bindable capability indicates that it can
+      be pointed by tosca.relationships.network.BindsTo relationship type, which
+      represents a network association relationship between Port and Compute node
+      types.
+
+  tosca.capabilities.OperatingSystem:
+    derived_from: tosca.capabilities.Root
+    properties:
+      architecture:
+        required: false
+        type: string
+        description: >
+          The host Operating System (OS) architecture.
+      type:
+        required: false
+        type: string
+        description: >
+          The host Operating System (OS) type.
+      distribution:
+        required: false
+        type: string
+        description: >
+          The host Operating System (OS) distribution. Examples of valid values
+          for an “type” of “Linux” would include:
+          debian, fedora, rhel and ubuntu.
+      version:
+        required: false
+        type: version
+        description: >
+          The host Operating System version.
+
+  tosca.capabilities.Container.Docker:
+    derived_from: tosca.capabilities.Container
+    properties:
+      version:
+        type: list
+        required: false
+        entry_schema:
+          type: version
+        description: >
+          The Docker version capability.
+      publish_all:
+        type: boolean
+        default: false
+        required: false
+        description: >
+          Indicates that all ports (ranges) listed in the dockerfile
+          using the EXPOSE keyword be published.
+      publish_ports:
+        type: list
+        entry_schema:
+          type: tosca.datatypes.network.PortSpec
+        required: false
+        description: >
+          List of ports mappings from source (Docker container)
+          to target (host) ports to publish.
+      expose_ports:
+        type: list
+        entry_schema:
+          type: tosca.datatypes.network.PortSpec
+        required: false
+        description: >
+          List of ports mappings from source (Docker container) to expose
+          to other Docker containers (not accessible outside host).
+      volumes:
+        type: list
+        entry_schema:
+          type: string
+        required: false
+        description: >
+          The dockerfile VOLUME command which is used to enable access
+          from the Docker container to a directory on the host machine.
+      host_id:
+        type: string
+        required: false
+        description: >
+            The optional identifier of an existing host resource
+            that should be used to run this container on.
+      volume_id:
+        type: string
+        required: false
+        description: >
+          The optional identifier of an existing storage volume (resource)
+          that should be used to create the container's mount point(s) on.
+
+##########################################################################
+ # Interfaces Type.
+ # The Interfaces element describes a list of one or more interface
+ # definitions for a modelable entity (e.g., a Node or Relationship Type)
+ # as defined within the TOSCA Simple Profile specification.
+##########################################################################
+interface_types:
+  tosca.interfaces.node.lifecycle.Standard:
+    create:
+      description: Standard lifecycle create operation.
+    configure:
+      description: Standard lifecycle configure operation.
+    start:
+      description: Standard lifecycle start operation.
+    stop:
+      description: Standard lifecycle stop operation.
+    delete:
+      description: Standard lifecycle delete operation.
+
+  tosca.interfaces.relationship.Configure:
+    pre_configure_source:
+      description: Operation to pre-configure the source endpoint.
+    pre_configure_target:
+      description: Operation to pre-configure the target endpoint.
+    post_configure_source:
+      description: Operation to post-configure the source endpoint.
+    post_configure_target:
+      description: Operation to post-configure the target endpoint.
+    add_target:
+      description: Operation to add a target node.
+    remove_target:
+      description: Operation to remove a target node.
+    add_source: >
+      description: Operation to notify the target node of a source node which
+      is now available via a relationship.
+      description:
+    target_changed: >
+      description: Operation to notify source some property or attribute of the
+      target changed
+
+##########################################################################
+ # Data Type.
+ # A Datatype is a complex data type declaration which contains other
+ # complex or simple data types.
+##########################################################################
+data_types:
+  tosca.datatypes.Root:
+    description: >
+      The TOSCA root Data Type all other TOSCA base Data Types derive from
+    
+  tosca.datatypes.network.NetworkInfo:
+    derived_from: tosca.datatypes.Root
+    properties:
+      network_name:
+        type: string
+      network_id:
+        type: string
+      addresses:
+        type: list
+        entry_schema:
+          type: string
+
+  tosca.datatypes.network.PortInfo:
+    derived_from: tosca.datatypes.Root
+    properties:
+      port_name:
+        type: string
+      port_id:
+        type: string
+      network_id:
+        type: string
+      mac_address:
+        type: string
+      addresses:
+        type: list
+        entry_schema:
+          type: string
+
+  tosca.datatypes.network.PortDef:
+    derived_from: tosca.datatypes.Root
+    type: integer
+    constraints:
+      - in_range: [ 1, 65535 ]
+
+  tosca.datatypes.network.PortSpec:
+    derived_from: tosca.datatypes.Root
+    properties:
+      protocol:
+        type: string
+        required: true
+        default: tcp
+        constraints:
+          - valid_values: [ udp, tcp, igmp ]
+      target:
+        type: tosca.datatypes.network.PortDef
+        required: false
+      target_range:
+        type: range
+        required: false
+        constraints:
+          - in_range: [ 1, 65535 ]
+      source:
+        type: tosca.datatypes.network.PortDef
+        required: false
+      source_range:
+        type: range
+        required: false
+        constraints:
+          - in_range: [ 1, 65535 ]
+
+  tosca.datatypes.Credential:
+    derived_from: tosca.datatypes.Root
+    properties:
+      protocol:
+        type: string
+        required: false
+      token_type:
+        type: string
+        default: password
+        required: true
+      token:
+        type: string
+        required: true
+      keys:
+        type: map
+        entry_schema:
+          type: string
+        required: false
+      user:
+        type: string
+        required: false
+
+##########################################################################
+ # Artifact Type.
+ # An Artifact Type is a reusable entity that defines the type of one or more
+ # files which Node Types or Node Templates can have dependent relationships
+ # and used during operations such as during installation or deployment.
+##########################################################################
+artifact_types:
+  tosca.artifacts.Root:
+    description: >
+      The TOSCA Artifact Type all other TOSCA Artifact Types derive from
+    properties:
+      version: version
+
+  tosca.artifacts.File:
+    derived_from: tosca.artifacts.Root
+
+  tosca.artifacts.Deployment:
+    derived_from: tosca.artifacts.Root
+    description: TOSCA base type for deployment artifacts
+
+  tosca.artifacts.Deployment.Image:
+    derived_from: tosca.artifacts.Deployment
+
+  tosca.artifacts.Deployment.Image.VM:
+    derived_from: tosca.artifacts.Deployment.Image
+
+  tosca.artifacts.Implementation:
+    derived_from: tosca.artifacts.Root
+    description: TOSCA base type for implementation artifacts
+
+  tosca.artifacts.Implementation.Bash:
+    derived_from: tosca.artifacts.Implementation
+    description: Script artifact for the Unix Bash shell
+    mime_type: application/x-sh
+    file_ext: [ sh ]
+
+  tosca.artifacts.Implementation.Python:
+    derived_from: tosca.artifacts.Implementation
+    description: Artifact for the interpreted Python language
+    mime_type: application/x-python
+    file_ext: [ py ]
+
+  tosca.artifacts.Deployment.Image.Container.Docker:
+    derived_from: tosca.artifacts.Deployment.Image
+    description: Docker container image
+
+  tosca.artifacts.Deployment.Image.VM.ISO:
+    derived_from: tosca.artifacts.Deployment.Image
+    description: Virtual Machine (VM) image in ISO disk format
+    mime_type: application/octet-stream
+    file_ext: [ iso ]
+
+  tosca.artifacts.Deployment.Image.VM.QCOW2:
+    derived_from: tosca.artifacts.Deployment.Image
+    description: Virtual Machine (VM) image in QCOW v2 standard disk format
+    mime_type: application/octet-stream
+    file_ext: [ qcow2 ]
+
+##########################################################################
+ # Policy Type.
+ # TOSCA Policy Types represent logical grouping of TOSCA nodes that have
+ # an implied relationship and need to be orchestrated or managed together
+ # to achieve some result.
+##########################################################################
+policy_types:
+  tosca.policies.Root:
+    description: The TOSCA Policy Type all other TOSCA Policy Types derive from.
+
+  tosca.policies.Placement:
+    derived_from: tosca.policies.Root
+    description: The TOSCA Policy Type definition that is used to govern
+      placement of TOSCA nodes or groups of nodes.
+
+  tosca.policies.Scaling:
+    derived_from: tosca.policies.Root
+    description: The TOSCA Policy Type definition that is used to govern
+      scaling of TOSCA nodes or groups of nodes.
+
+  tosca.policies.Monitoring:
+    derived_from: tosca.policies.Root
+    description: The TOSCA Policy Type definition that is used to govern
+      monitoring of TOSCA nodes or groups of nodes.
+
+  tosca.policies.Update:
+    derived_from: tosca.policies.Root
+    description: The TOSCA Policy Type definition that is used to govern
+      update of TOSCA nodes or groups of nodes.
+
+  tosca.policies.Performance:
+    derived_from: tosca.policies.Root
+    description: The TOSCA Policy Type definition that is used to declare
+      performance requirements for TOSCA nodes or groups of nodes.
+
+##########################################################################
+ # Group Type.
+ # Group Type represents logical grouping of TOSCA nodes that have an
+ # implied membership relationship and may need to be orchestrated or
+ # managed together to achieve some result.
+##########################################################################
+group_types:
+  tosca.groups.Root:
+    description: The TOSCA Group Type all other TOSCA Group Types derive from
+    interfaces:
+      Standard:
+        type: tosca.interfaces.node.lifecycle.Standard
diff --git a/src/main/resources/extensions/nfv/TOSCA_nfv_definition_1_0.yaml b/src/main/resources/extensions/nfv/TOSCA_nfv_definition_1_0.yaml
new file mode 100644
index 0000000..365d70e
--- /dev/null
+++ b/src/main/resources/extensions/nfv/TOSCA_nfv_definition_1_0.yaml
@@ -0,0 +1,240 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+##########################################################################
+# The content of this file reflects TOSCA NFV Profile in YAML version
+# 1.0.0. It describes the definition for TOSCA NFV types including Node Type,
+# Relationship Type, Capability Type and Interfaces.
+##########################################################################
+tosca_definitions_version: tosca_simple_profile_for_nfv_1_0_0
+
+##########################################################################
+# Node Type.
+# A Node Type is a reusable entity that defines the type of one or more
+# Node Templates.
+##########################################################################
+node_types:
+  tosca.nodes.nfv.VNF:
+    derived_from: tosca.nodes.Root   # Or should this be its own top - level type?
+    properties:
+      id:
+        type: string
+        description: ID of this VNF
+      vendor:
+        type: string
+        description: name of the vendor who generate this VNF
+      version:
+        type: version
+        description: version of the software for this VNF
+    requirements:
+      - virtualLink:
+          capability: tosca.capabilities.nfv.VirtualLinkable
+          relationship: tosca.relationships.nfv.VirtualLinksTo
+          node: tosca.nodes.nfv.VL
+
+  tosca.nodes.nfv.VDU:
+    derived_from: tosca.nodes.Compute
+    capabilities:
+      high_availability:
+        type: tosca.capabilities.nfv.HA
+      virtualbinding:
+        type: tosca.capabilities.nfv.VirtualBindable
+      monitoring_parameter:
+        type: tosca.capabilities.nfv.Metric
+    requirements:
+      - high_availability:
+          capability: tosca.capabilities.nfv.HA
+          relationship: tosca.relationships.nfv.HA
+          node: tosca.nodes.nfv.VDU
+          occurrences: [ 0, 1 ]
+
+  tosca.nodes.nfv.CP:
+    derived_from: tosca.nodes.network.Port
+    properties:
+      type:
+        type: string
+        required: false
+    requirements:
+      - virtualLink:
+          capability: tosca.capabilities.nfv.VirtualLinkable
+          relationship: tosca.relationships.nfv.VirtualLinksTo
+          node: tosca.nodes.nfv.VL
+      - virtualBinding:
+          capability: tosca.capabilities.nfv.VirtualBindable
+          relationship: tosca.relationships.nfv.VirtualBindsTo
+          node: tosca.nodes.nfv.VDU
+    attributes:
+      address:
+        type: string
+
+  tosca.nodes.nfv.VL:
+    derived_from: tosca.nodes.network.Network
+    properties:
+      vendor:
+        type: string
+        required: true
+        description: name of the vendor who generate this VL
+    capabilities:
+      virtual_linkable:
+        type: tosca.capabilities.nfv.VirtualLinkable
+
+  tosca.nodes.nfv.VL.ELine:
+    derived_from: tosca.nodes.nfv.VL
+    capabilities:
+      virtual_linkable:
+        occurrences: 2
+
+  tosca.nodes.nfv.VL.ELAN:
+    derived_from: tosca.nodes.nfv.VL
+
+  tosca.nodes.nfv.VL.ETree:
+    derived_from: tosca.nodes.nfv.VL
+
+  tosca.nodes.nfv.FP:
+    derived_from: tosca.nodes.Root
+    properties:
+      policy:
+        type: string
+        required: false
+        description: name of the vendor who generate this VL
+    requirements:
+      - forwarder:
+          capability: tosca.capabilities.nfv.Forwarder
+          relationship: tosca.relationships.nfv.ForwardsTo
+
+##########################################################################
+# Relationship Type.
+# A Relationship Type is a reusable entity that defines the type of one
+# or more relationships between Node Types or Node Templates.
+##########################################################################
+
+relationship_types:
+  tosca.relationships.nfv.VirtualLinksTo:
+    derived_from: tosca.relationships.network.LinksTo
+    valid_target_types: [ tosca.capabilities.nfv.VirtualLinkable ]
+
+  tosca.relationships.nfv.VirtualBindsTo:
+    derived_from: tosca.relationships.network.BindsTo
+    valid_target_types: [ tosca.capabilities.nfv.VirtualBindable ]
+
+  tosca.relationships.nfv.HA:
+    derived_from: tosca.relationships.Root
+    valid_target_types: [ tosca.capabilities.nfv.HA ]
+
+  tosca.relationships.nfv.Monitor:
+    derived_from: tosca.relationships.ConnectsTo
+    valid_target_types: [ tosca.capabilities.nfv.Metric ]
+
+  tosca.relationships.nfv.ForwardsTo:
+    derived_from: tosca.relationships.root
+    valid_target_types: [ tosca.capabilities.nfv.Forwarder]
+
+##########################################################################
+# Capability Type.
+# A Capability Type is a reusable entity that describes a kind of
+# capability that a Node Type can declare to expose.
+##########################################################################
+
+capability_types:
+  tosca.capabilities.nfv.VirtualLinkable:
+    derived_from: tosca.capabilities.network.Linkable
+
+  tosca.capabilities.nfv.VirtualBindable:
+    derived_from: tosca.capabilities.network.Bindable
+
+  tosca.capabilities.nfv.HA:
+    derived_from: tosca.capabilities.Root
+    valid_source_types: [ tosca.nodes.nfv.VDU ]
+
+  tosca.capabilities.nfv.HA.ActiveActive:
+    derived_from: tosca.capabilities.nfv.HA
+
+  tosca.capabilities.nfv.HA.ActivePassive:
+    derived_from: tosca.capabilities.nfv.HA
+
+  tosca.capabilities.nfv.Metric:
+    derived_from: tosca.capabilities.Root
+
+  tosca.capabilities.nfv.Forwarder:
+    derived_from: tosca.capabilities.Root
+
+##########################################################################
+ # Interfaces Type.
+ # The Interfaces element describes a list of one or more interface
+ # definitions for a modelable entity (e.g., a Node or Relationship Type)
+ # as defined within the TOSCA Simple Profile specification.
+##########################################################################
+
+##########################################################################
+ # Data Type.
+ # A Datatype is a complex data type declaration which contains other
+ # complex or simple data types.
+##########################################################################
+
+##########################################################################
+ # Artifact Type.
+ # An Artifact Type is a reusable entity that defines the type of one or more
+ # files which Node Types or Node Templates can have dependent relationships
+ # and used during operations such as during installation or deployment.
+##########################################################################
+
+##########################################################################
+ # Policy Type.
+ # TOSCA Policy Types represent logical grouping of TOSCA nodes that have
+ # an implied relationship and need to be orchestrated or managed together
+ # to achieve some result.
+##########################################################################
+
+##########################################################################
+ # Group Type
+ #
+##########################################################################
+group_types:
+  tosca.groups.nfv.VNFFG:
+    derived_from: tosca.groups.Root
+
+    properties:
+      vendor:
+        type: string
+        required: true
+        description: name of the vendor who generate this VNFFG
+
+      version:
+        type: string
+        required: true
+        description: version of this VNFFG
+
+      number_of_endpoints:
+        type: integer
+        required: true
+        description: count of the external endpoints included in this VNFFG
+
+      dependent_virtual_link:
+        type: list
+        entry_schema:
+          type: string
+        required: true
+        description: Reference to a VLD  used in this Forwarding Graph
+
+      connection_point:
+        type: list
+        entry_schema:
+          type: string
+        required: true
+        description: Reference to Connection Points forming the VNFFG
+
+      constituent_vnfs:
+        type: list
+        entry_schema:
+          type: string
+        required: true
+        description: Reference to a list of  VNFD used in this VNF Forwarding Graph
diff --git a/src/main/resources/extensions/nfv/nfv.py b/src/main/resources/extensions/nfv/nfv.py
new file mode 100644
index 0000000..0c7c2b9
--- /dev/null
+++ b/src/main/resources/extensions/nfv/nfv.py
@@ -0,0 +1,19 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+# VERSION and DEFS_FILE are required for all extensions
+
+VERSION = 'tosca_simple_profile_for_nfv_1_0_0'
+
+DEFS_FILE = "TOSCA_nfv_definition_1_0.yaml"
+
+SECTIONS = ('metadata')