Onboard TOSCA data_types defined in package

Onboard TOSCA data_types defined in a CSAR package
that does not exists in the SDC default data_types
library. Those data_types were being lost.
All data_types declared in the package will be
included in the "GlobalSubstitutionServiceTemplate".
This includes the data_types declared in the main
topology template and in its imported definition
files.
Defines a maven profile to compile the catalog-be
in the main SDC pom.

Change-Id: I39445b0f42e924dc1015945b7e605e804c1d505b
Issue-ID: SDC-2763
Signed-off-by: André Schmid <andre.schmid@est.tech>
Signed-off-by: Vasyl Razinkov <vasyl.razinkov@est.tech>

9 files changed, 293 insertions, 159 deletions

diff --git a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-api/src/main/java/org/openecomp/core/converter/ServiceTemplateReaderService.java b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-api/src/main/java/org/openecomp/core/converter/ServiceTemplateReaderService.java
index 8a97957be9..3a0b2ce401 100644
--- a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-api/src/main/java/org/openecomp/core/converter/ServiceTemplateReaderService.java
+++ b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-api/src/main/java/org/openecomp/core/converter/ServiceTemplateReaderService.java
@@ -1,5 +1,4 @@
-
-/*-
+/*
  * ============LICENSE_START=======================================================
  *  Modification Copyright (C) 2019 Nordix Foundation.
  * ================================================================================
@@ -26,7 +25,7 @@ import java.util.Map;
 
 public interface ServiceTemplateReaderService {
 
-    Map<String, Object> readServiceTemplate(byte[] serivceTemplateContent);
+    Map<String, Object> readServiceTemplate(byte[] serviceTemplateContent);
 
     Object getMetadata();
 
@@ -47,4 +46,6 @@ public interface ServiceTemplateReaderService {
     List<Object> getImports();
 
     Map<String, Object> getPolicies();
+
+    Map<String, Object> getDataTypes();
 }
diff --git a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/AbstractToscaConverter.java b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/AbstractToscaConverter.java
index 6619a4c580..43ae3c9f38 100644
--- a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/AbstractToscaConverter.java
+++ b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/AbstractToscaConverter.java
@@ -33,7 +33,6 @@ import static org.openecomp.core.impl.GlobalSubstitutionServiceTemplate.HEAT_IND
 import static org.openecomp.core.impl.GlobalSubstitutionServiceTemplate.ONAP_INDEX_IMPORT_FILE;
 import static org.openecomp.sdc.tosca.csar.CSARConstants.TOSCA_META_ORIG_PATH_FILE_NAME;
 import static org.openecomp.sdc.tosca.csar.ToscaMetadataFileInfo.TOSCA_META_PATH_FILE_NAME;
-
 import java.io.File;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -43,7 +42,9 @@ import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
 import java.util.regex.Pattern;
+import javax.validation.constraints.NotNull;
 import org.apache.commons.collections.MapUtils;
+import org.onap.sdc.tosca.datatypes.model.DataType;
 import org.onap.sdc.tosca.datatypes.model.Import;
 import org.onap.sdc.tosca.datatypes.model.NodeType;
 import org.onap.sdc.tosca.datatypes.model.ServiceTemplate;
@@ -60,11 +61,14 @@ import org.openecomp.sdc.tosca.datatypes.ToscaServiceModel;
 import org.openecomp.sdc.tosca.services.DataModelUtil;
 import org.openecomp.sdc.tosca.services.ToscaUtil;
 import org.openecomp.sdc.translator.services.heattotosca.globaltypes.GlobalTypesGenerator;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.yaml.snakeyaml.error.YAMLException;
 
 public abstract class AbstractToscaConverter implements ToscaConverter {
+    private static final Logger LOGGER = LoggerFactory.getLogger(AbstractToscaConverter.class);
 
-    public abstract void convertTopologyTemplate(ServiceTemplate serviceTemplate,
+    public abstract void convertTopologyTemplate(@NotNull ServiceTemplate serviceTemplate,
                                                  ServiceTemplateReaderService readerService);
 
     protected void handleMetadataFile(Map<String, byte[]> csarFiles) {
@@ -74,8 +78,8 @@ public abstract class AbstractToscaConverter implements ToscaConverter {
         }
     }
 
-    protected void handleDefintionTemplate(String key, Map<String, byte[]> csarFiles,
-                                           GlobalSubstitutionServiceTemplate gsst) {
+    protected void handleDefinitionTemplate(String key, Map<String, byte[]> csarFiles,
+                                            GlobalSubstitutionServiceTemplate gsst) {
         try {
             ServiceTemplateReaderService readerService = new ServiceTemplateReaderServiceImpl(csarFiles.get(key));
             Object nodeTypes = readerService.getNodeTypes();
@@ -83,6 +87,7 @@ public abstract class AbstractToscaConverter implements ToscaConverter {
                 Map<String, NodeType> nodeTypeMap = (Map<String, NodeType>) nodeTypes;
                 gsst.appendNodes(nodeTypeMap);
             }
+            gsst.appendDataTypes((Map) readerService.getDataTypes());
         } catch (YAMLException ye) {
             throw new CoreException(new ErrorCode.ErrorCodeBuilder()
                     .withMessage("Invalid YAML content in file " + key)
@@ -158,6 +163,7 @@ public abstract class AbstractToscaConverter implements ToscaConverter {
             convertToscaVersion(serviceTemplate, readerService);
             convertImports(serviceTemplate);
             convertNodeTypes(serviceTemplate, readerService);
+            convertDataTypes(serviceTemplate, readerService);
             convertTopologyTemplate(serviceTemplate, readerService);
         } catch (YAMLException ye) {
             throw new CoreException(new ErrorCode.ErrorCodeBuilder()
@@ -228,6 +234,22 @@ public abstract class AbstractToscaConverter implements ToscaConverter {
         }
     }
 
+    protected void convertDataTypes(final ServiceTemplate serviceTemplate,
+                                    final ServiceTemplateReaderService readerService) {
+        try {
+            final Map<String, Object> dataTypes = readerService.getDataTypes();
+            for (final Map.Entry<String, Object> entry : dataTypes.entrySet()) {
+                final Optional<DataType> dataType =
+                        ToscaConverterUtil.createObjectFromClass(entry.getKey(), entry.getValue(), DataType.class);
+
+                dataType.ifPresent(
+                        nodeTypeValue -> DataModelUtil.addDataType(serviceTemplate, entry.getKey(), nodeTypeValue));
+            }
+        } catch (final Exception ex) {
+            LOGGER.error("Unable to process data types: ", ex);
+        }
+    }
+
     protected CsarFileTypes getFileType(String fileName) {
         if (isMainServiceTemplate(fileName)) {
             return CsarFileTypes.mainServiceTemplate;
diff --git a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/AbstractToscaSolConverter.java b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/AbstractToscaSolConverter.java
index 6349963841..f94d2bf5dd 100644
--- a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/AbstractToscaSolConverter.java
+++ b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/AbstractToscaSolConverter.java
@@ -32,6 +32,7 @@ import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 import org.onap.sdc.tosca.datatypes.model.ServiceTemplate;
+import org.openecomp.core.converter.ServiceTemplateReaderService;
 import org.openecomp.core.utilities.file.FileContentHandler;
 import org.openecomp.sdc.logging.api.Logger;
 import org.openecomp.sdc.logging.api.LoggerFactory;
@@ -87,9 +88,11 @@ public abstract class AbstractToscaSolConverter extends AbstractToscaConverter {
         if (toscaDefinitionImportHandler.hasError()) {
             throw new InvalidToscaDefinitionImportException(toscaDefinitionImportHandler.getErrors());
         }
-        handledDefinitionFilesList.addAll(toscaDefinitionImportHandler.getHandledDefinitionFilesList());
+        final Map<String, ServiceTemplateReaderService> handledImportDefinitionFileMap =
+            toscaDefinitionImportHandler.getHandledImportDefinitionFileMap();
+        handledDefinitionFilesList.addAll(handledImportDefinitionFileMap.keySet());
         for (final String file : handledDefinitionFilesList) {
-            handleDefintionTemplate(file, csarFiles, gsst);
+            handleDefinitionTemplate(file, csarFiles, gsst);
         }
     }
 
diff --git a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/GlobalSubstitutionServiceTemplate.java b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/GlobalSubstitutionServiceTemplate.java
index f6955bbdad..98d8d23751 100644
--- a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/GlobalSubstitutionServiceTemplate.java
+++ b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/GlobalSubstitutionServiceTemplate.java
@@ -16,43 +16,44 @@
 
 package org.openecomp.core.impl;
 
+import static org.openecomp.core.converter.datatypes.Constants.ONAP_INDEX;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Optional;
+import java.util.stream.Collectors;
 import org.apache.commons.collections4.MapUtils;
+import org.onap.sdc.tosca.datatypes.model.DataType;
 import org.onap.sdc.tosca.datatypes.model.Import;
 import org.onap.sdc.tosca.datatypes.model.NodeType;
 import org.onap.sdc.tosca.datatypes.model.ServiceTemplate;
 import org.openecomp.core.utilities.orchestration.OnboardingTypesEnum;
-import org.openecomp.sdc.logging.api.Logger;
-import org.openecomp.sdc.logging.api.LoggerFactory;
 import org.openecomp.sdc.translator.services.heattotosca.globaltypes.GlobalTypesGenerator;
 
-import java.util.*;
-
-import static org.openecomp.core.converter.datatypes.Constants.ONAP_INDEX;
-
 public class GlobalSubstitutionServiceTemplate extends ServiceTemplate {
-    private static final Logger logger = LoggerFactory.getLogger(ServiceTemplate.class);
 
     public static final String GLOBAL_SUBSTITUTION_SERVICE_FILE_NAME =
         "GlobalSubstitutionTypesServiceTemplate.yaml";
     public static final String TEMPLATE_NAME_PROPERTY = "template_name";
-    public static final String DEFININTION_VERSION = "tosca_simple_yaml_1_0_0";
+    public static final String DEFINITION_VERSION = "tosca_simple_yaml_1_0_0";
     public static final String HEAT_INDEX = "openecomp_heat_index";
     public static final String HEAT_INDEX_IMPORT_FILE = "openecomp-heat/_index.yml";
     public static final String ONAP_INDEX_IMPORT_FILE = "onap/_index.yml";
-    private static final Map<String, ServiceTemplate> globalServiceTemplates =
-        GlobalTypesGenerator.getGlobalTypesServiceTemplate(OnboardingTypesEnum.CSAR);
+
+    // transient needed to avoid being parsed as a YAML String. Used parser is reading fields instead of getters,
+    // although it ignores static or transient fields.
+    private final transient Map<String, ServiceTemplate> globalServiceTemplates;
+    private final transient Map<String, DataType> globalDataTypeMap;
 
     public GlobalSubstitutionServiceTemplate() {
         super();
         init();
-    }
-
-
-    public void appendNodes(Map<String, NodeType> nodes) {
-        Optional<Map<String, NodeType>> nodeTypesToAdd =
-            removeExistingGlobalTypes(nodes);
-
-        nodeTypesToAdd.ifPresent(nodeTypes -> getNode_types().putAll(nodeTypes));
+        globalServiceTemplates =
+            GlobalTypesGenerator.getGlobalTypesServiceTemplate(OnboardingTypesEnum.CSAR);
+        globalDataTypeMap = loadGlobalDataTypes();
     }
 
     public void init()   {
@@ -60,6 +61,24 @@ public class GlobalSubstitutionServiceTemplate extends ServiceTemplate {
         writeMetadataSection();
         writeImportsSection();
         setNode_types(new HashMap<>());
+        setData_types(new HashMap<>());
+    }
+
+    public void appendNodes(final Map<String, NodeType> nodes) {
+        final Optional<Map<String, NodeType>> nodeTypesToAdd = findNonGlobalTypesNodes(nodes);
+        nodeTypesToAdd.ifPresent(nodeTypes -> getNode_types().putAll(nodeTypes));
+    }
+
+    public void appendDataTypes(final Map<String, DataType> dataTypeMap) {
+        if (MapUtils.isEmpty(dataTypeMap)) {
+            return;
+        }
+        dataTypeMap.entrySet().stream()
+            .filter(dataTypeEntry -> !isGlobalDataType(dataTypeEntry.getKey()))
+            .forEach(dataTypeEntry -> {
+                final Optional<DataType> dataType = parseDataTypeToYamlObject(dataTypeEntry);
+                dataType.ifPresent(dataType1 -> getData_types().put(dataTypeEntry.getKey(), dataType1));
+            });
     }
 
     private void writeImportsSection() {
@@ -83,24 +102,20 @@ public class GlobalSubstitutionServiceTemplate extends ServiceTemplate {
     }
 
     private void writeDefinitionSection() {
-        setTosca_definitions_version(DEFININTION_VERSION);
+        setTosca_definitions_version(DEFINITION_VERSION);
     }
 
-    private Optional<Map<String, NodeType>> removeExistingGlobalTypes(Map<String, NodeType> nodes){
-        Map<String, NodeType> nodeTypesToAdd = new HashMap<>();
-        ServiceTemplate serviceTemplate = globalServiceTemplates.get("openecomp/nodes.yml");
-
-        if(Objects.isNull(serviceTemplate) || MapUtils.isEmpty(serviceTemplate.getNode_types())){
+    private Optional<Map<String, NodeType>> findNonGlobalTypesNodes(final Map<String, NodeType> nodes){
+        final Map<String, NodeType> globalNodeTypes = getAllGlobalNodeTypes();
+        if (MapUtils.isEmpty(globalNodeTypes)) {
             return Optional.of(nodes);
         }
 
-        Map<String, NodeType> globalNodeTypes = getAllGlobalNodeTypes();
+        final Map<String, NodeType> nodeTypesToAdd = new HashMap<>();
+
         for(Map.Entry<String, NodeType> nodeTypeEntry : nodes.entrySet()){
             if(!globalNodeTypes.containsKey(nodeTypeEntry.getKey())){
-                Optional<NodeType> nodeType =
-                    ToscaConverterUtil
-                        .createObjectFromClass(nodeTypeEntry.getKey(), nodeTypeEntry.getValue(), NodeType.class);
-
+                Optional<NodeType> nodeType = parseNodeTypeToYamlObject(nodeTypeEntry);
                 nodeType
                     .ifPresent(nodeTypeValue -> nodeTypesToAdd.put(nodeTypeEntry.getKey(), nodeTypeValue));
             }
@@ -109,6 +124,32 @@ public class GlobalSubstitutionServiceTemplate extends ServiceTemplate {
         return Optional.of(nodeTypesToAdd);
     }
 
+    private boolean isGlobalDataType(final String dataType) {
+        if (MapUtils.isEmpty(globalDataTypeMap)) {
+            return false;
+        }
+
+        return globalDataTypeMap.containsKey(dataType);
+    }
+
+    private Optional<NodeType> parseNodeTypeToYamlObject(final Entry<String, NodeType> nodeTypeEntry) {
+        return ToscaConverterUtil
+            .createObjectFromClass(nodeTypeEntry.getKey(), nodeTypeEntry.getValue(), NodeType.class);
+    }
+
+    private Optional<DataType> parseDataTypeToYamlObject(final Entry<String, DataType> dataTypeEntry) {
+        return ToscaConverterUtil
+            .createObjectFromClass(dataTypeEntry.getKey(), dataTypeEntry.getValue(), DataType.class);
+    }
+
+    private Map<String, DataType> loadGlobalDataTypes() {
+        return globalServiceTemplates.values().stream()
+            .map(ServiceTemplate::getData_types)
+            .filter(MapUtils::isNotEmpty)
+            .flatMap(stringDataTypeMap -> stringDataTypeMap.entrySet().stream())
+            .collect(Collectors.toMap(Entry::getKey, Entry::getValue, (dataType, dataType2) -> dataType));
+    }
+
     private Map<String, NodeType> getAllGlobalNodeTypes(){
         Map<String, NodeType> globalNodeTypes = new HashMap<>();
 
diff --git a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/ToscaConverterImpl.java b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/ToscaConverterImpl.java
index 8d4b9850ea..fcc6f0ab31 100644
--- a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/ToscaConverterImpl.java
+++ b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/ToscaConverterImpl.java
@@ -55,7 +55,7 @@ public class ToscaConverterImpl extends AbstractToscaConverter {
                   break;
 
               case definitionsFile:
-                  handleDefintionTemplate(fileEntry.getKey(), csarFiles, gsst);
+                  handleDefinitionTemplate(fileEntry.getKey(), csarFiles, gsst);
                   break;
 
               default:
diff --git a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/ToscaDefinitionImportHandler.java b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/ToscaDefinitionImportHandler.java
index 8422c89f2e..661cadc738 100644
--- a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/ToscaDefinitionImportHandler.java
+++ b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/ToscaDefinitionImportHandler.java
@@ -23,10 +23,13 @@ import static org.openecomp.sdc.tosca.csar.CSARConstants.NON_FILE_IMPORT_ATTRIBU
 
 import java.net.URI;
 import java.util.ArrayList;
-import java.util.LinkedHashSet;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
+import java.util.Map.Entry;
+import java.util.Optional;
+import lombok.Getter;
+import org.apache.commons.collections.CollectionUtils;
 import org.apache.commons.io.FilenameUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.openecomp.core.converter.ServiceTemplateReaderService;
@@ -34,14 +37,23 @@ import org.openecomp.core.impl.services.ServiceTemplateReaderServiceImpl;
 import org.openecomp.sdc.common.errors.Messages;
 import org.openecomp.sdc.datatypes.error.ErrorLevel;
 import org.openecomp.sdc.datatypes.error.ErrorMessage;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Handles TOSCA definition imports, checking for import definition errors.
  */
 public class ToscaDefinitionImportHandler {
 
+    private static final Logger LOGGER = LoggerFactory.getLogger(ToscaDefinitionImportHandler.class);
+
     private final Map<String, byte[]> fileMap;
-    private final Set<String> handledDefinitionFilesList = new LinkedHashSet<>();
+
+    /**
+     * Stores all processed files during the import handling
+     */
+    @Getter
+    private final Map<String, ServiceTemplateReaderService> handledImportDefinitionFileMap = new HashMap<>();
     private final List<ErrorMessage> validationErrorList = new ArrayList<>();
     private String currentFile;
 
@@ -50,9 +62,39 @@ public class ToscaDefinitionImportHandler {
      * @param fileStructureMap      The package structure with file path and respective file byte
      * @param mainDefinitionFilePath    The main descriptor yaml file to start the reading
      */
-    public ToscaDefinitionImportHandler(final Map<String, byte[]> fileStructureMap, final String mainDefinitionFilePath) {
+    public ToscaDefinitionImportHandler(final Map<String, byte[]> fileStructureMap,
+                                        final String mainDefinitionFilePath) {
         this.fileMap = fileStructureMap;
-        handleImports(mainDefinitionFilePath);
+        readImportsFromMainDefinition(mainDefinitionFilePath);
+    }
+
+    private void readImportsFromMainDefinition(final String mainDefinitionFilePath) {
+        if(!checkMainDefinitionExists(mainDefinitionFilePath)) {
+            return;
+        }
+        final ServiceTemplateReaderService readerService = parseToServiceTemplate(mainDefinitionFilePath).orElse(null);
+        if (readerService == null) {
+            return;
+        }
+        final List<String> importFileList = extractFileImports(readerService.getImports());
+        if (CollectionUtils.isNotEmpty(importFileList)) {
+            for (final String importFilePath : importFileList) {
+                final String resolvedPath = resolveImportPath(FilenameUtils.getPath(mainDefinitionFilePath), importFilePath);
+                handleImports(resolvedPath);
+            }
+        }
+    }
+
+    private Optional<ServiceTemplateReaderService> parseToServiceTemplate(final String definitionFile) {
+        try {
+            return Optional.of(new ServiceTemplateReaderServiceImpl(fileMap.get(definitionFile)));
+        } catch (final Exception ex) {
+            LOGGER.debug("Could not parse '{}' to a ServiceTemplateReader", definitionFile, ex);
+            reportError(ErrorLevel.ERROR,
+                String.format(Messages.INVALID_YAML_FORMAT.getErrorMessage(), ex.getMessage()));
+        }
+
+        return Optional.empty();
     }
 
     /**
@@ -67,23 +109,18 @@ public class ToscaDefinitionImportHandler {
         if (!checkImportExists(fileName)) {
             return;
         }
-        final ServiceTemplateReaderService readerService;
-        try {
-            readerService = new ServiceTemplateReaderServiceImpl(fileMap.get(fileName));
-        } catch (final Exception ex) {
-            reportError(ErrorLevel.ERROR,
-                String.format(Messages.INVALID_YAML_FORMAT.getErrorMessage(), ex.getMessage()));
+        final ServiceTemplateReaderService readerService = parseToServiceTemplate(fileName).orElse(null);
+        if (readerService == null) {
             return;
         }
-        handledDefinitionFilesList.add(fileName);
+
+        handledImportDefinitionFileMap.put(fileName, readerService);
         final List<Object> imports = readerService.getImports();
         final List<String> extractImportFiles = extractFileImports(imports);
-        for (final String importedFile : extractImportFiles) {
-            final String resolvedPath = resolveImportPath(FilenameUtils.getPath(fileName), importedFile);
-            if (!handledDefinitionFilesList.contains(resolvedPath)) {
-                handleImports(resolvedPath);
-            }
-        }
+        extractImportFiles.stream()
+            .map(importedFile -> resolveImportPath(FilenameUtils.getPath(fileName), importedFile))
+            .filter(resolvedPath -> !handledImportDefinitionFileMap.containsKey(resolvedPath))
+            .forEach(this::handleImports);
     }
 
     /**
@@ -129,7 +166,7 @@ public class ToscaDefinitionImportHandler {
             importedFileList.add((String) importObject);
         } else if (importObject instanceof Map) {
             final Map<String, Object> importObjectMap = (Map) importObject;
-            for (final Map.Entry entry : importObjectMap.entrySet()) {
+            for (final Entry<String, Object> entry : importObjectMap.entrySet()) {
                 if (NON_FILE_IMPORT_ATTRIBUTES.stream().noneMatch(attr -> entry.getKey().equals(attr))) {
                     importedFileList.addAll(readImportStatement(entry.getValue()));
                 }
@@ -175,17 +212,26 @@ public class ToscaDefinitionImportHandler {
         return resolvedImportPath;
     }
 
+    private boolean checkImportExists(final String filePath) {
+        return checkFileExists(filePath, Messages.MISSING_IMPORT_FILE.formatMessage(filePath));
+    }
+
+    private boolean checkMainDefinitionExists(final String filePath) {
+        return checkFileExists(filePath, Messages.MISSING_MAIN_DEFINITION_FILE.formatMessage(filePath));
+    }
+
     /**
      * Checks if the given file path exists inside the file structure.
      * Reports an error if the file was not found.
      *
      * @param filePath  file path to check inside the file structure
+     * @param errorMsg  the error message to report
      * @return
      *  {@code true} if the file exists, {@code false} otherwise
      */
-    private boolean checkImportExists(final String filePath) {
-        if (!fileMap.keySet().contains(filePath)) {
-            reportError(ErrorLevel.ERROR, Messages.MISSING_IMPORT_FILE.formatMessage(filePath));
+    private boolean checkFileExists(final String filePath, final String errorMsg) {
+        if (!fileMap.containsKey(filePath)) {
+            reportError(ErrorLevel.ERROR, errorMsg);
             return false;
         }
 
@@ -193,15 +239,6 @@ public class ToscaDefinitionImportHandler {
     }
 
     /**
-     * Gets all processed files during the import handling.
-     * @return
-     *  A list containing the processed files paths
-     */
-    public Set<String> getHandledDefinitionFilesList() {
-        return handledDefinitionFilesList;
-    }
-
-    /**
      * Adds an error to the validation error list.
      *
      * @param errorLevel        the error level
diff --git a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/services/ServiceTemplateReaderServiceImpl.java b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/services/ServiceTemplateReaderServiceImpl.java
index 9b1c0126c7..a74ec8eb7c 100644
--- a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/services/ServiceTemplateReaderServiceImpl.java
+++ b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/main/java/org/openecomp/core/impl/services/ServiceTemplateReaderServiceImpl.java
@@ -20,21 +20,29 @@
 
 package org.openecomp.core.impl.services;
 
-import org.onap.sdc.tosca.services.YamlUtil;
-import org.openecomp.core.converter.ServiceTemplateReaderService;
+import static org.openecomp.core.converter.datatypes.Constants.POLICIES;
+import static org.openecomp.core.converter.datatypes.Constants.inputs;
+import static org.openecomp.core.converter.datatypes.Constants.metadata;
+import static org.openecomp.core.converter.datatypes.Constants.nodeTemplates;
+import static org.openecomp.core.converter.datatypes.Constants.nodeTypes;
+import static org.openecomp.core.converter.datatypes.Constants.outputs;
+import static org.openecomp.core.converter.datatypes.Constants.substitutionMappings;
+import static org.openecomp.core.converter.datatypes.Constants.topologyTemplate;
+import static org.openecomp.sdc.be.utils.TypeUtils.ToscaTagNamesEnum.DATA_TYPES;
+import static org.openecomp.sdc.be.utils.TypeUtils.ToscaTagNamesEnum.IMPORTS;
+import static org.openecomp.sdc.be.utils.TypeUtils.ToscaTagNamesEnum.TOSCA_VERSION;
 
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import org.openecomp.sdc.be.utils.TypeUtils.ToscaTagNamesEnum;
-
-import static org.openecomp.core.converter.datatypes.Constants.*;
+import org.onap.sdc.tosca.services.YamlUtil;
+import org.openecomp.core.converter.ServiceTemplateReaderService;
 
 public class ServiceTemplateReaderServiceImpl implements ServiceTemplateReaderService {
 
-    private Map<String, Object> readServiceTemplate = new HashMap<>();
+    private final Map<String, Object> readServiceTemplate;
 
     public ServiceTemplateReaderServiceImpl(byte[] serviceTemplateContent) {
         this.readServiceTemplate = readServiceTemplate(serviceTemplateContent);
@@ -42,22 +50,21 @@ public class ServiceTemplateReaderServiceImpl implements ServiceTemplateReaderSe
 
     @Override
     public Map<String, Object> readServiceTemplate(byte[] serviceTemplateContent) {
-
         return new YamlUtil().yamlToObject(new String(serviceTemplateContent), Map.class);
-
     }
 
     @Override
     public List<Object> getImports() {
-        return Objects.isNull(this.readServiceTemplate.get("imports")) ? new ArrayList<>()
-                       : (List<Object>) this.readServiceTemplate.get("imports");
+        final String importsElementName = IMPORTS.getElementName();
+        return Objects.isNull(this.readServiceTemplate.get(importsElementName)) ? new ArrayList<>()
+            : (List<Object>) this.readServiceTemplate.get(importsElementName);
     }
 
     @Override
     public Map<String, Object> getPolicies() {
         Map<String, Object> policiesAsMap = new HashMap<>();
         if (!Objects.isNull(this.getTopologyTemplate()) && !Objects.isNull(
-                ((Map<String, Object>) this.getTopologyTemplate()).get(POLICIES))) {
+            ((Map<String, Object>) this.getTopologyTemplate()).get(POLICIES))) {
             policiesAsMap = (Map<String, Object>) ((Map<String, Object>) this.getTopologyTemplate()).get(POLICIES);
         }
         return policiesAsMap;
@@ -70,13 +77,13 @@ public class ServiceTemplateReaderServiceImpl implements ServiceTemplateReaderSe
 
     @Override
     public Object getToscaVersion() {
-        return this.readServiceTemplate.get(ToscaTagNamesEnum.TOSCA_VERSION.getElementName());
+        return this.readServiceTemplate.get(TOSCA_VERSION.getElementName());
     }
 
     @Override
     public Map<String, Object> getNodeTypes() {
         return Objects.isNull(this.readServiceTemplate.get(nodeTypes)) ? new HashMap<>()
-                       : (Map<String, Object>) this.readServiceTemplate.get(nodeTypes);
+            : (Map<String, Object>) this.readServiceTemplate.get(nodeTypes);
     }
 
     @Override
@@ -87,25 +94,32 @@ public class ServiceTemplateReaderServiceImpl implements ServiceTemplateReaderSe
     @Override
     public Map<String, Object> getNodeTemplates() {
         return Objects.isNull(this.getTopologyTemplate()) ? new HashMap<>()
-                       : (Map<String, Object>) ((Map<String, Object>) this.getTopologyTemplate()).get(nodeTemplates);
+            : (Map<String, Object>) ((Map<String, Object>) this.getTopologyTemplate()).get(nodeTemplates);
     }
 
     @Override
     public Map<String, Object> getInputs() {
         return Objects.isNull(this.getTopologyTemplate()) ? new HashMap<>()
-                       : (Map<String, Object>) ((Map<String, Object>) this.getTopologyTemplate()).get(inputs);
+            : (Map<String, Object>) ((Map<String, Object>) this.getTopologyTemplate()).get(inputs);
     }
 
     @Override
     public Map<String, Object> getOutputs() {
         return Objects.isNull(this.getTopologyTemplate()) ? new HashMap<>()
-                       : (Map<String, Object>) ((Map<String, Object>) this.getTopologyTemplate()).get(outputs);
+            : (Map<String, Object>) ((Map<String, Object>) this.getTopologyTemplate()).get(outputs);
     }
 
     @Override
     public Map<String, Object> getSubstitutionMappings() {
         return Objects.isNull(this.getTopologyTemplate()) ? new HashMap<>()
-                       : (Map<String, Object>) ((Map<String, Object>) this.getTopologyTemplate())
-                                                       .get(substitutionMappings);
+            : (Map<String, Object>) ((Map<String, Object>) this.getTopologyTemplate())
+                .get(substitutionMappings);
+    }
+
+    @Override
+    public Map<String, Object> getDataTypes() {
+        final String dataTypesElementName = DATA_TYPES.getElementName();
+        return Objects.isNull(this.readServiceTemplate.get(dataTypesElementName)) ? new HashMap<>()
+            : (Map<String, Object>) this.readServiceTemplate.get(dataTypesElementName);
     }
 }
diff --git a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/test/java/org/openecomp/core/impl/ToscaConvertorDefinitionsTest.java b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/test/java/org/openecomp/core/impl/ToscaConvertorDefinitionsTest.java
index b978b7db99..8167cce3aa 100644
--- a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/test/java/org/openecomp/core/impl/ToscaConvertorDefinitionsTest.java
+++ b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/test/java/org/openecomp/core/impl/ToscaConvertorDefinitionsTest.java
@@ -64,7 +64,7 @@ public class ToscaConvertorDefinitionsTest {
         assertTrue(((Map) serviceTemplate.getImports().get(0)).containsKey(HEAT_INDEX));
         assertTrue(((Map) serviceTemplate.getImports().get(0)).containsKey(ONAP_INDEX));
 
-        assertEquals(DEFININTION_VERSION, serviceTemplate.getTosca_definitions_version());
+        assertEquals(DEFINITION_VERSION, serviceTemplate.getTosca_definitions_version());
 
 
         assertNotNull(serviceTemplate.getNode_types());
diff --git a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/test/java/org/openecomp/core/impl/ToscaDefinitionImportHandlerTest.java b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/test/java/org/openecomp/core/impl/ToscaDefinitionImportHandlerTest.java
index fe0d5a8620..6f0901cfdb 100644
--- a/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/test/java/org/openecomp/core/impl/ToscaDefinitionImportHandlerTest.java
+++ b/openecomp-be/lib/openecomp-tosca-converter-lib/openecomp-tosca-converter-core/src/test/java/org/openecomp/core/impl/ToscaDefinitionImportHandlerTest.java
@@ -21,6 +21,8 @@ package org.openecomp.core.impl;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.containsInAnyOrder;
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.hasItem;
 import static org.hamcrest.Matchers.hasSize;
 import static org.openecomp.sdc.be.test.util.TestResourcesHandler.getResourceBytesOrFail;
 
@@ -32,9 +34,10 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
+import java.util.stream.Collectors;
 import org.junit.Before;
 import org.junit.Test;
+import org.openecomp.core.converter.ServiceTemplateReaderService;
 import org.openecomp.sdc.common.errors.Messages;
 import org.openecomp.sdc.datatypes.error.ErrorLevel;
 import org.openecomp.sdc.datatypes.error.ErrorMessage;
@@ -54,7 +57,10 @@ public class ToscaDefinitionImportHandlerTest {
      */
     @Test
     public void testGivenDescriptorFiles_whenMainDescriptorImportsAreHandled_allDescriptorsAreProcessedWithoutError() {
-        final List<String> filesToHandleList = Arrays.asList("Definitions/Main.yaml", "Definitions/descriptorBasicImport.yaml",
+        final String mainDefinitionFilePath = "Definitions/Main.yaml";
+        descriptorFileMap
+            .put(mainDefinitionFilePath, getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(mainDefinitionFilePath)));
+        final List<String> filesToHandleList = Arrays.asList("Definitions/descriptorBasicImport.yaml",
             "Definitions/descriptorWithRelativePaths.yaml", "Artifacts/descriptorWithAbsolutePaths.yaml",
             "Artifacts/descriptorCyclicReference.yaml");
 
@@ -64,12 +70,14 @@ public class ToscaDefinitionImportHandlerTest {
 
         final ToscaDefinitionImportHandler toscaDefinitionImportHandler = new ToscaDefinitionImportHandler(
             descriptorFileMap,
-            "Definitions/Main.yaml");
-        final Set<String> actualHandledFiles = toscaDefinitionImportHandler.getHandledDefinitionFilesList();
+            mainDefinitionFilePath);
+        final Map<String, ServiceTemplateReaderService> actualHandledFiles =
+            toscaDefinitionImportHandler.getHandledImportDefinitionFileMap();
 
-        assertThat("The handled files should be the same", actualHandledFiles, hasSize(filesToHandleList.size()));
+        assertThat("The handled files should be the same",
+            actualHandledFiles.keySet(), hasSize(filesToHandleList.size()));
         assertThat("The handled files should be the same"
-            , actualHandledFiles, containsInAnyOrder(filesToHandleList.toArray(new String[0]))
+            , actualHandledFiles.keySet(), containsInAnyOrder(filesToHandleList.toArray(new String[0]))
         );
 
         final List<ErrorMessage> validationErrorList = toscaDefinitionImportHandler.getErrors();
@@ -83,19 +91,20 @@ public class ToscaDefinitionImportHandlerTest {
     public void testGivenEmptyPackage_whenMainDescriptorIsHandled_aMissingFileErrorIsReported() {
         final List<String> filesToHandleList = Collections.emptyList();
 
-        final ToscaDefinitionImportHandler toscaDefinitionImportHandler = new ToscaDefinitionImportHandler(
-            descriptorFileMap,
-            "Definitions/Main.yaml");
-        final Set<String> actualHandledFiles = toscaDefinitionImportHandler.getHandledDefinitionFilesList();
+        final ToscaDefinitionImportHandler toscaDefinitionImportHandler =
+            new ToscaDefinitionImportHandler(descriptorFileMap, "Definitions/Main.yaml");
+        final Map<String, ServiceTemplateReaderService> actualHandledFiles =
+            toscaDefinitionImportHandler.getHandledImportDefinitionFileMap();
 
-        assertThat("The handled files should be the same", actualHandledFiles, hasSize(filesToHandleList.size()));
+        assertThat("The handled files should be the same",
+            actualHandledFiles.keySet(), hasSize(filesToHandleList.size()));
         assertThat("The handled files should be the same"
-            , actualHandledFiles, containsInAnyOrder(filesToHandleList.toArray(new String[0]))
+            , actualHandledFiles.keySet(), containsInAnyOrder(filesToHandleList.toArray(new String[0]))
         );
 
         final List<ErrorMessage> expectedErrorList = new ArrayList<>();
         expectedErrorList.add(new ErrorMessage(ErrorLevel.ERROR,
-            Messages.MISSING_IMPORT_FILE.formatMessage("Definitions/Main.yaml")));
+            Messages.MISSING_MAIN_DEFINITION_FILE.formatMessage("Definitions/Main.yaml")));
 
         final List<ErrorMessage> validationErrorList = toscaDefinitionImportHandler.getErrors();
         assertThat("The errors should be the same", validationErrorList, hasSize(expectedErrorList.size()));
@@ -109,25 +118,30 @@ public class ToscaDefinitionImportHandlerTest {
      */
     @Test
     public void testGivenOneMissingDescriptorFile_whenMainDescriptorImportsAreHandled_aMissingFileErrorIsReported() {
-        final List<String> filesToHandleList = Arrays.asList("Definitions/Main.yaml",
-            "Definitions/descriptorBasicImport.yaml", "Definitions/descriptorWithRelativePaths.yaml",
-            "Artifacts/descriptorWithAbsolutePaths.yaml");
+        descriptorFileMap
+            .put("Definitions/Main.yaml",
+                getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve("Definitions/Main.yaml")));
+
+        final List<String> filesToHandleList = Arrays.asList("Definitions/descriptorBasicImport.yaml",
+            "Definitions/descriptorWithRelativePaths.yaml", "Artifacts/descriptorWithAbsolutePaths.yaml");
         filesToHandleList.forEach(file ->
             descriptorFileMap.put(file, getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(file)))
         );
 
         final List<ErrorMessage> expectedErrorList = new ArrayList<>();
         expectedErrorList.add(new ErrorMessage(ErrorLevel.ERROR,
-            String.format(Messages.MISSING_IMPORT_FILE.getErrorMessage(), "Artifacts/descriptorCyclicReference.yaml")));
+            Messages.MISSING_IMPORT_FILE.formatMessage("Artifacts/descriptorCyclicReference.yaml")));
 
         final ToscaDefinitionImportHandler toscaDefinitionImportHandler = new ToscaDefinitionImportHandler(
             descriptorFileMap,
             "Definitions/Main.yaml");
-        final Set<String> actualHandledFiles = toscaDefinitionImportHandler.getHandledDefinitionFilesList();
+        final Map<String, ServiceTemplateReaderService> actualHandledFiles =
+            toscaDefinitionImportHandler.getHandledImportDefinitionFileMap();
 
-        assertThat("The handled files should be the same", actualHandledFiles, hasSize(filesToHandleList.size()));
+        assertThat("The handled files should be the same",
+            actualHandledFiles.keySet(), hasSize(filesToHandleList.size()));
         assertThat("The handled files should be the same"
-            , actualHandledFiles, containsInAnyOrder(filesToHandleList.toArray(new String[0]))
+            , actualHandledFiles.keySet(), containsInAnyOrder(filesToHandleList.toArray(new String[0]))
         );
 
         final List<ErrorMessage> validationErrorList = toscaDefinitionImportHandler.getErrors();
@@ -143,25 +157,30 @@ public class ToscaDefinitionImportHandlerTest {
     @Test
     public void testGivenDescriptorWithInvalidImportStatement_whenMainDescriptorImportsAreHandled_aInvalidImportStatementErrorIsReported() {
         final String mainDefinitionFile = "Definitions/MainWithInvalidImportedFile.yaml";
+        descriptorFileMap
+            .put(mainDefinitionFile, getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(mainDefinitionFile)));
 
-        final List<String> filesToHandleList = Arrays.asList(mainDefinitionFile,
-            "Definitions/descriptorInvalidImportStatement.yaml");
+        final List<String> filesToHandleList =
+            Collections.singletonList("Definitions/descriptorInvalidImportStatement.yaml");
         filesToHandleList.forEach(file ->
             descriptorFileMap.put(file, getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(file)))
         );
 
         final List<ErrorMessage> expectedErrorList = new ArrayList<>();
         expectedErrorList.add(new ErrorMessage(ErrorLevel.ERROR,
-            Messages.INVALID_IMPORT_STATEMENT.formatMessage("Definitions/descriptorInvalidImportStatement.yaml", "null")));
+            Messages.INVALID_IMPORT_STATEMENT
+                .formatMessage("Definitions/descriptorInvalidImportStatement.yaml", "null"))
+        );
 
         final ToscaDefinitionImportHandler toscaDefinitionImportHandler = new ToscaDefinitionImportHandler(
             descriptorFileMap,
             mainDefinitionFile);
-        final Set<String> actualHandledFiles = toscaDefinitionImportHandler.getHandledDefinitionFilesList();
+        final Map<String, ServiceTemplateReaderService> actualHandledFiles = toscaDefinitionImportHandler.getHandledImportDefinitionFileMap();
 
-        assertThat("The handled files should be the same", actualHandledFiles, hasSize(filesToHandleList.size()));
+        assertThat("The handled files should be the same",
+            actualHandledFiles.keySet(), hasSize(filesToHandleList.size()));
         assertThat("The handled files should be the same"
-            , actualHandledFiles, containsInAnyOrder(filesToHandleList.toArray(new String[0]))
+            , actualHandledFiles.keySet(), containsInAnyOrder(filesToHandleList.toArray(new String[0]))
         );
 
         final List<ErrorMessage> validationErrorList = toscaDefinitionImportHandler.getErrors();
@@ -179,20 +198,22 @@ public class ToscaDefinitionImportHandlerTest {
         final String mainDefinitionFilePath = "Definitions/Main1.yaml";
         final String invalidMainDefinitionFilePath = "../Definitions/InvalidMainDefinitionFile.yaml";
 
-        final List<String> filesToHandleList = Arrays.asList(mainDefinitionFilePath);
+        final List<String> filesToHandleList = Collections.singletonList(mainDefinitionFilePath);
         filesToHandleList.forEach(file ->
             descriptorFileMap.put(file, getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(file)))
         );
 
         final List<ErrorMessage> expectedErrorList = new ArrayList<>();
-        expectedErrorList.add(new ErrorMessage(ErrorLevel.ERROR, Messages.MISSING_IMPORT_FILE.formatMessage(invalidMainDefinitionFilePath)));
+        expectedErrorList.add(new ErrorMessage(ErrorLevel.ERROR,
+            Messages.MISSING_MAIN_DEFINITION_FILE.formatMessage(invalidMainDefinitionFilePath)));
 
         final ToscaDefinitionImportHandler toscaDefinitionImportHandler = new ToscaDefinitionImportHandler(
             descriptorFileMap,
             invalidMainDefinitionFilePath);
-        final Set<String> actualHandledFiles = toscaDefinitionImportHandler.getHandledDefinitionFilesList();
+        final Map<String, ServiceTemplateReaderService> actualHandledFiles =
+            toscaDefinitionImportHandler.getHandledImportDefinitionFileMap();
 
-        assertThat("No files should be handled", actualHandledFiles, hasSize(0));
+        assertThat("No files should be handled", actualHandledFiles.keySet(), hasSize(0));
 
         final List<ErrorMessage> validationErrorList = toscaDefinitionImportHandler.getErrors();
 
@@ -208,36 +229,27 @@ public class ToscaDefinitionImportHandlerTest {
     @Test
     public void testGivenInvalidYamlDescriptorFile_whenDescriptorIsHandled_aInvalidYamlFormatErrorIsReported() {
         final String mainDefinitionFile = "Definitions/descriptorInvalid.yaml";
-
-        final List<String> filesToHandleList = Arrays.asList(mainDefinitionFile);
-        filesToHandleList.forEach(file ->
-            descriptorFileMap.put(file, getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(file)))
-        );
-
+        descriptorFileMap.put(mainDefinitionFile,
+            getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(mainDefinitionFile)));
         final List<ErrorMessage> expectedErrorList = new ArrayList<>();
-        expectedErrorList.add(new ErrorMessage(ErrorLevel.ERROR, String.format(Messages.INVALID_YAML_FORMAT.getErrorMessage()
-            , "while scanning a simple key\n"
-                + " in 'string', line 5, column 3:\n"
-                + "      template_author= onap\n"
-                + "      ^\n"
-                + "could not find expected ':'\n"
-                + " in 'string', line 6, column 1:\n"
-                + "    description: vCPE_vgw\n"
-                + "    ^\n")));
+        expectedErrorList
+            .add(new ErrorMessage(ErrorLevel.ERROR, Messages.INVALID_YAML_FORMAT.formatMessage("")));
 
-        final ToscaDefinitionImportHandler toscaDefinitionImportHandler = new ToscaDefinitionImportHandler(
-            descriptorFileMap,
-            mainDefinitionFile);
-        final Set<String> actualHandledFiles = toscaDefinitionImportHandler.getHandledDefinitionFilesList();
+        final ToscaDefinitionImportHandler toscaDefinitionImportHandler =
+            new ToscaDefinitionImportHandler(descriptorFileMap, mainDefinitionFile);
+        final Map<String, ServiceTemplateReaderService> actualHandledFiles =
+            toscaDefinitionImportHandler.getHandledImportDefinitionFileMap();
 
-        assertThat("No files should be handled", actualHandledFiles, hasSize(0));
+        assertThat("No files should be handled", actualHandledFiles.keySet(), hasSize(0));
 
         final List<ErrorMessage> validationErrorList = toscaDefinitionImportHandler.getErrors();
 
         assertThat("The errors should be the same", validationErrorList, hasSize(expectedErrorList.size()));
-        assertThat("The errors should be the same"
-            , validationErrorList, containsInAnyOrder(expectedErrorList.toArray(new ErrorMessage[0]))
-        );
+        final List<String> actualErrorListAsStringList = validationErrorList.stream()
+            .map(ErrorMessage::getMessage)
+            .collect(Collectors.toList());
+        expectedErrorList.forEach(expectedString ->
+            assertThat(actualErrorListAsStringList, hasItem(containsString(expectedString.getMessage()))));
     }
 
     /**
@@ -246,19 +258,24 @@ public class ToscaDefinitionImportHandlerTest {
     @Test
     public void testGivenDescriptorFiles_whenMainDescriptorWithDifferentImportStatementsIsHandled_noErrorsAreReported() {
         final String mainDefinitionFile = "Definitions/descriptorFileWithValidImportStatements.yaml";
+        descriptorFileMap.put(mainDefinitionFile,
+            getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(mainDefinitionFile)));
 
-        final List<String> filesToHandleList = Arrays.asList(mainDefinitionFile, "Artifacts/descriptorCyclicReference.yaml");
-        filesToHandleList.forEach(file ->
+        final List<String> importDescriptorToHandleList =
+            Collections.singletonList("Artifacts/descriptorCyclicReference.yaml");
+        importDescriptorToHandleList.forEach(file ->
             descriptorFileMap.put(file, getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(file)))
         );
 
         final ToscaDefinitionImportHandler toscaDefinitionImportHandler =
             new ToscaDefinitionImportHandler(descriptorFileMap, mainDefinitionFile);
-        final Set<String> actualHandledFiles = toscaDefinitionImportHandler.getHandledDefinitionFilesList();
+        final Map<String, ServiceTemplateReaderService> actualHandledFiles =
+            toscaDefinitionImportHandler.getHandledImportDefinitionFileMap();
 
-        assertThat("The handled files should be the same", actualHandledFiles, hasSize(filesToHandleList.size()));
+        assertThat("The handled files should be the same",
+            actualHandledFiles.keySet(), hasSize(importDescriptorToHandleList.size()));
         assertThat("The handled files should be the same"
-            , actualHandledFiles, containsInAnyOrder(filesToHandleList.toArray(new String[0]))
+            , actualHandledFiles.keySet(), containsInAnyOrder(importDescriptorToHandleList.toArray(new String[0]))
         );
 
         final List<ErrorMessage> validationErrorList = toscaDefinitionImportHandler.getErrors();
@@ -271,8 +288,9 @@ public class ToscaDefinitionImportHandlerTest {
     @Test
     public void testGivenDescriptorFileWithNonexistentRelativeImport_whenIncorrectMainDescriptorIsHandled_aMissingFileErrorIsReported() {
         final String mainDefinitionFile = "Definitions/MainWithNonexistentReferences.yaml";
-
-        final List<String> filesToHandleList = Arrays.asList(mainDefinitionFile,
+        descriptorFileMap
+            .put(mainDefinitionFile, getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(mainDefinitionFile)));
+        final List<String> filesToHandleList = Arrays.asList(
             "Definitions/descriptorNonexistentImport.yaml", "Artifacts/descriptorCyclicReference.yaml");
         filesToHandleList.forEach(file ->
             descriptorFileMap.put(file, getResourceBytesOrFail(RESOURCES_FILE_PATH.resolve(file)))
@@ -280,26 +298,24 @@ public class ToscaDefinitionImportHandlerTest {
 
         final List<ErrorMessage> expectedErrorList = new ArrayList<>();
         expectedErrorList.add(new ErrorMessage(ErrorLevel.ERROR,
-            String.format(Messages.MISSING_IMPORT_FILE.getErrorMessage(),
-                "Definitions/descriptorCyclicReference.yaml"))
-        );
+            Messages.MISSING_IMPORT_FILE.formatMessage("Definitions/descriptorCyclicReference.yaml")));
         expectedErrorList.add(new ErrorMessage(ErrorLevel.ERROR,
-            String.format(Messages.MISSING_IMPORT_FILE.getErrorMessage(),
-                "Definitions/descriptorCyclicReference.yaml"))
+            Messages.MISSING_IMPORT_FILE.formatMessage("Definitions/descriptorCyclicReference.yaml"))
         );
         expectedErrorList.add(new ErrorMessage(ErrorLevel.ERROR,
-            String.format(Messages.MISSING_IMPORT_FILE.getErrorMessage(),
-                "Definitions/descriptorCyclicReference.yaml"))
+            Messages.MISSING_IMPORT_FILE.formatMessage("Definitions/descriptorCyclicReference.yaml"))
         );
 
         final ToscaDefinitionImportHandler toscaDefinitionImportHandler = new ToscaDefinitionImportHandler(
             descriptorFileMap,
             mainDefinitionFile);
-        final Set<String> actualHandledFiles = toscaDefinitionImportHandler.getHandledDefinitionFilesList();
+        final Map<String, ServiceTemplateReaderService> actualHandledFiles =
+            toscaDefinitionImportHandler.getHandledImportDefinitionFileMap();
 
-        assertThat("The handled files should be the same", actualHandledFiles, hasSize(filesToHandleList.size()));
+        assertThat("The handled files should be the same",
+            actualHandledFiles.keySet(), hasSize(filesToHandleList.size()));
         assertThat("The handled files should be the same"
-            , actualHandledFiles, containsInAnyOrder(filesToHandleList.toArray(new String[0]))
+            , actualHandledFiles.keySet(), containsInAnyOrder(filesToHandleList.toArray(new String[0]))
         );
 
         final List<ErrorMessage> validationErrorList = toscaDefinitionImportHandler.getErrors();