Add class model for workflow and resource data type.

Change-Id: Ia42f56541bef0418dddb797c019ecda3afa6983b
Issue-ID: CCSDK-1380
Signed-off-by: Brinda Santh <brindasanth@in.ibm.com>

6 files changed, 296 insertions, 22 deletions

diff --git a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/BluePrintExtensionFunctions.kt b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/BluePrintExtensionFunctions.kt
new file mode 100644
index 000000000..dafd076fb
--- /dev/null
+++ b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/BluePrintExtensionFunctions.kt
@@ -0,0 +1,126 @@
+/*
+ *  Copyright © 2019 IBM.
+ *
+ *  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.
+ */
+
+package org.onap.ccsdk.cds.controllerblueprints.core
+
+import org.onap.ccsdk.cds.controllerblueprints.core.annotations.*
+import org.onap.ccsdk.cds.controllerblueprints.core.data.ConstraintClause
+import org.onap.ccsdk.cds.controllerblueprints.core.data.DataType
+import org.onap.ccsdk.cds.controllerblueprints.core.data.EntrySchema
+import org.onap.ccsdk.cds.controllerblueprints.core.data.PropertyDefinition
+import org.onap.ccsdk.cds.controllerblueprints.core.dsl.*
+import kotlin.reflect.KClass
+import kotlin.reflect.KProperty1
+import kotlin.reflect.KType
+import kotlin.reflect.full.declaredMemberProperties
+
+fun <T : KClass<*>> T.asBluePrintsDataTypes(): DataType {
+    val annotation = this.annotations.filter { it is BluePrintsDataType }.single() as BluePrintsDataType
+    checkNotNull(annotation) { "BluePrintsDataType annotation definition not found" }
+    val dataType = DataType().apply {
+        id = annotation.name
+        version = annotation.version
+        derivedFrom = annotation.derivedFrom
+        description = annotation.description
+    }
+    dataType.properties = this.asPropertyDefinitionMap()
+    return dataType
+}
+
+fun <T : KClass<*>> T.asPropertyDefinitionMap(): MutableMap<String, PropertyDefinition> {
+    val properties: MutableMap<String, PropertyDefinition> = hashMapOf()
+    this.declaredMemberProperties.forEach { member ->
+        properties[member.name] = member.asPropertyDefinition()
+    }
+    return properties
+}
+
+fun <T> KProperty1<T, *>.asPropertyDefinition(): PropertyDefinition {
+    val property = PropertyDefinition()
+    property.id = this.name
+    val getter = this.getter
+    property.required = !this.returnType.isMarkedNullable
+    property.type = this.returnType.asBluePrintsDataType(this.name)
+    if (this.returnType.arguments.isNotEmpty()) {
+        property.entrySchema = this.returnType.entitySchema()
+    }
+    this.annotations.forEach { fieldAnnotation ->
+        //println("Field : ${this.name} : Annotation : $fieldAnnotation")
+        when (fieldAnnotation) {
+            is BluePrintsProperty ->
+                property.description = fieldAnnotation.description
+            is PropertyDefaultValue ->
+                property.value = fieldAnnotation.value.asJsonType(property.type)
+            is BluePrintsConstrain -> {
+                if (property.constraints == null) property.constraints = arrayListOf()
+                property.constraints!!.add(fieldAnnotation.asBluePrintConstraintClause())
+            }
+            is InputExpression -> {
+                property.value = getInput(fieldAnnotation.propertyName)
+            }
+            is PropertyExpression -> {
+                property.value = getNodeTemplateProperty(fieldAnnotation.modelableEntityName,
+                        fieldAnnotation.propertyName, fieldAnnotation.subPropertyName)
+            }
+            is AttributeExpression -> {
+                property.value = getNodeTemplateAttribute(fieldAnnotation.modelableEntityName,
+                        fieldAnnotation.attributeName, fieldAnnotation.subAttributeName)
+            }
+            is ArtifactExpression -> {
+                property.value = getNodeTemplateArtifact(fieldAnnotation.modelableEntityName,
+                        fieldAnnotation.artifactName)
+            }
+            is OperationOutputExpression -> {
+                property.value = getNodeTemplateOperationOutput(fieldAnnotation.modelableEntityName,
+                        fieldAnnotation.interfaceName, fieldAnnotation.propertyName, fieldAnnotation.subPropertyName)
+            }
+            is DSLExpression -> {
+                property.value = dslExpression(fieldAnnotation.propertyName)
+            }
+        }
+    }
+    return property
+}
+
+internal fun BluePrintsConstrain.asBluePrintConstraintClause(): ConstraintClause {
+    TODO()
+}
+
+internal fun <T : KType> T.entitySchema(): EntrySchema {
+    val entrySchema = EntrySchema()
+    if (this.arguments.size == 1) {
+        entrySchema.type = this.arguments[0].type!!.asBluePrintsDataType("")
+    } else if (this.arguments.size == 2) {
+        entrySchema.type = this.arguments[1].type!!.asBluePrintsDataType("")
+    }
+    return entrySchema
+}
+
+internal fun <T : KType> T.asBluePrintsDataType(propertyName: String): String {
+    val simpleName = (this.classifier as? KClass<*>)?.java?.simpleName
+            ?: throw BluePrintException("filed to get simple name.")
+    return when (simpleName) {
+        "String", "Date" -> BluePrintConstants.DATA_TYPE_STRING
+        "int" -> BluePrintConstants.DATA_TYPE_INTEGER
+        "Boolean" -> BluePrintConstants.DATA_TYPE_BOOLEAN
+        "Float" -> BluePrintConstants.DATA_TYPE_FLOAT
+        "Double" -> BluePrintConstants.DATA_TYPE_DOUBLE
+        "List" ->  BluePrintConstants.DATA_TYPE_LIST
+        "Map" -> BluePrintConstants.DATA_TYPE_MAP
+        "Object", "JsonNode", "ObjectNode", "ArrayNode" -> BluePrintConstants.DATA_TYPE_JSON
+        else -> simpleName
+    }
+}
\ No newline at end of file
diff --git a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/CustomFunctions.kt b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/CustomFunctions.kt
index d148745df..c77427b01 100644
--- a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/CustomFunctions.kt
+++ b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/CustomFunctions.kt
@@ -24,6 +24,7 @@ import org.onap.ccsdk.cds.controllerblueprints.core.utils.JacksonUtils
 import org.onap.ccsdk.cds.controllerblueprints.core.utils.JsonParserUtils
 import org.slf4j.LoggerFactory
 import org.slf4j.helpers.MessageFormatter
+import java.lang.Float
 import kotlin.reflect.KClass
 
 /**
@@ -93,6 +94,19 @@ fun <T : Any?> T.asJsonPrimitive(): JsonNode {
     }
 }
 
+/** Based on Blueprint DataType Convert string value to JsonNode Type **/
+fun String.asJsonType(bpDataType: String): JsonNode {
+    return when (bpDataType.toLowerCase()) {
+        BluePrintConstants.DATA_TYPE_STRING -> this.asJsonPrimitive()
+        BluePrintConstants.DATA_TYPE_BOOLEAN -> java.lang.Boolean.valueOf(this).asJsonPrimitive()
+        BluePrintConstants.DATA_TYPE_INTEGER -> Integer.valueOf(this).asJsonPrimitive()
+        BluePrintConstants.DATA_TYPE_FLOAT -> Float.valueOf(this).asJsonPrimitive()
+        BluePrintConstants.DATA_TYPE_DOUBLE -> java.lang.Double.valueOf(this).asJsonPrimitive()
+        // For List, Map and Complex Types.
+        else -> this.jsonAsJsonType()
+    }
+}
+
 /**
  * Utility to convert Complex or Primitive object to Json Type.
  */
@@ -156,6 +170,11 @@ fun ArrayNode.asListOfString(): List<String> {
     return JacksonUtils.getListFromJsonNode(this, String::class.java)
 }
 
+fun <T> JsonNode.asType(clazzType: Class<T>): T {
+    return JacksonUtils.readValue(this, clazzType)
+            ?: throw BluePrintException("couldn't convert JsonNode of type $clazzType")
+}
+
 fun JsonNode.asListOfString(): List<String> {
     check(this is ArrayNode) { "JsonNode is not of type ArrayNode" }
     return this.asListOfString()
@@ -260,6 +279,9 @@ fun isNotBlank(value: String?): Boolean {
     return value != null && value.isNotBlank()
 }
 
+fun <T : String> T?.emptyTONull(): String? {
+    return if (this == null || this.isEmpty()) null else this
+}
 
 fun nullToEmpty(value: String?): String {
     return if (isNotEmpty(value)) value!! else ""
diff --git a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/annotations/BluePrintsAnnotations.kt b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/annotations/BluePrintsAnnotations.kt
new file mode 100644
index 000000000..94392b992
--- /dev/null
+++ b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/annotations/BluePrintsAnnotations.kt
@@ -0,0 +1,97 @@
+/*
+ *  Copyright © 2019 IBM.
+ *
+ *  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.
+ */
+
+package org.onap.ccsdk.cds.controllerblueprints.core.annotations
+
+
+import org.onap.ccsdk.cds.controllerblueprints.core.BluePrintConstants
+import kotlin.reflect.KClass
+
+@Target(AnnotationTarget.CLASS)
+annotation class BluePrintsDataType(
+        val name: String,
+        val version: String = BluePrintConstants.DEFAULT_VERSION_NUMBER,
+        val description: String,
+        val derivedFrom: String = "tosca.datatypes.root"
+)
+
+@Target(AnnotationTarget.CLASS)
+annotation class BluePrintsWorkflowInput
+
+@Target(AnnotationTarget.CLASS)
+annotation class BluePrintsWorkflowOutput
+
+@Target(AnnotationTarget.CLASS)
+annotation class BluePrintsNodeType(val propertiesType: KClass<*>, val attributesType: KClass<*>,
+                                    val inputsType: KClass<*>, val outputsType: KClass<*>)
+
+@Target(AnnotationTarget.FIELD, AnnotationTarget.TYPE_PARAMETER, AnnotationTarget.PROPERTY)
+annotation class BluePrintsProperty(
+        val name: String = "",
+        val description: String = ""
+)
+
+@Target(AnnotationTarget.FIELD, AnnotationTarget.TYPE_PARAMETER, AnnotationTarget.PROPERTY)
+@Repeatable
+annotation class BluePrintsConstrain()
+
+@Target(AnnotationTarget.FIELD, AnnotationTarget.TYPE_PARAMETER, AnnotationTarget.PROPERTY)
+annotation class PropertyDefaultValue(val value: String)
+
+annotation class PropertyValidValue(val value: String)
+
+@Target(AnnotationTarget.FIELD, AnnotationTarget.TYPE_PARAMETER, AnnotationTarget.PROPERTY)
+annotation class InputExpression(
+        val propertyName: String
+)
+
+@Target(AnnotationTarget.FIELD, AnnotationTarget.TYPE_PARAMETER, AnnotationTarget.PROPERTY)
+annotation class PropertyExpression(
+        val modelableEntityName: String = "SELF",
+        val reqOrCapEntityName: String = "",
+        val propertyName: String,
+        val subPropertyName: String = ""
+)
+
+@Target(AnnotationTarget.FIELD, AnnotationTarget.TYPE_PARAMETER, AnnotationTarget.PROPERTY)
+annotation class AttributeExpression(
+        val modelableEntityName: String = "SELF",
+        val reqOrCapEntityName: String = "",
+        val attributeName: String,
+        val subAttributeName: String = ""
+)
+
+@Target(AnnotationTarget.FIELD, AnnotationTarget.TYPE_PARAMETER, AnnotationTarget.PROPERTY)
+annotation class ArtifactExpression(
+        val modelableEntityName: String = "SELF",
+        val artifactName: String,
+        val location: String = "LOCAL_FILE",
+        val remove: Boolean = false
+)
+
+@Target(AnnotationTarget.FIELD, AnnotationTarget.TYPE_PARAMETER, AnnotationTarget.PROPERTY)
+annotation class OperationOutputExpression(
+        val modelableEntityName: String = "SELF",
+        val interfaceName: String,
+        val operationName: String,
+        val propertyName: String,
+        val subPropertyName: String = ""
+)
+
+@Target(AnnotationTarget.FIELD, AnnotationTarget.TYPE_PARAMETER, AnnotationTarget.PROPERTY)
+annotation class DSLExpression(
+        val propertyName: String
+)
\ No newline at end of file
diff --git a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintDSL.kt b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintDSL.kt
index c88408f19..01c6a13be 100644
--- a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintDSL.kt
+++ b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintDSL.kt
@@ -19,6 +19,7 @@ package org.onap.ccsdk.cds.controllerblueprints.core.dsl
 import com.fasterxml.jackson.databind.JsonNode
 import org.onap.ccsdk.cds.controllerblueprints.core.BluePrintConstants
 import org.onap.ccsdk.cds.controllerblueprints.core.BluePrintTypes
+import org.onap.ccsdk.cds.controllerblueprints.core.asJsonPrimitive
 import org.onap.ccsdk.cds.controllerblueprints.core.data.*
 import org.onap.ccsdk.cds.controllerblueprints.core.jsonAsJsonType
 
@@ -63,56 +64,66 @@ fun relationshipType(id: String, version: String, derivedFrom: String, descripti
     return RelationshipTypeBuilder(id, version, derivedFrom, description).apply(block).build()
 }
 
+// DSL Function
+fun dslExpression(key: String): JsonNode {
+    return ("*$key").asJsonPrimitive()
+}
 // Input Function
 
-fun getInput(inputKey: String): JsonNode {
+fun getInput(inputKey: String, jsonPath: String? = null): JsonNode {
     return """{"get_input": "$inputKey"}""".jsonAsJsonType()
 }
 
-fun getAttribute(attributeId: String): JsonNode {
-    return """{"get_attribute": ["SELF", "$attributeId"]}""".jsonAsJsonType()
-}
-
-fun getAttribute(attributeId: String, jsonPath: String): JsonNode {
-    return """{"get_attribute": ["SELF", "$attributeId", "$jsonPath"]}""".jsonAsJsonType()
+fun getAttribute(attributeId: String, jsonPath: String? = null): JsonNode {
+    return getNodeTemplateAttribute("SELF", attributeId, jsonPath)
 }
 
 fun getNodeTemplateAttribute(nodeTemplateId: String, attributeId: String): JsonNode {
-    return """{"get_attribute": ["$nodeTemplateId", "$attributeId"]}""".jsonAsJsonType()
+    return getNodeTemplateAttribute(nodeTemplateId, attributeId, null)
 }
 
-fun getNodeTemplateAttribute(nodeTemplateId: String, attributeId: String, jsonPath: String): JsonNode {
-    return """{"get_attribute": ["$nodeTemplateId", "$attributeId", "$jsonPath]}""".jsonAsJsonType()
+fun getNodeTemplateAttribute(nodeTemplateId: String, attributeId: String, jsonPath: String?): JsonNode {
+    return if (jsonPath.isNullOrEmpty() || jsonPath.isNullOrBlank()) {
+        """{"get_attribute": ["$nodeTemplateId", "$attributeId"]}""".jsonAsJsonType()
+    } else {
+        """{"get_attribute": ["$nodeTemplateId", "$attributeId", "$jsonPath"]}""".jsonAsJsonType()
+    }
 }
 
 // Property Function
 
-fun getProperty(propertyId: String): JsonNode {
-    return """{"get_property": ["SELF", "$propertyId"]}""".jsonAsJsonType()
-}
-
-fun getProperty(propertyId: String, jsonPath: String): JsonNode {
-    return """{"get_property": ["SELF", "$propertyId", "$jsonPath"]}""".jsonAsJsonType()
+fun getProperty(propertyId: String, jsonPath: String? = null): JsonNode {
+    return getNodeTemplateProperty("SELF", propertyId, jsonPath)
 }
 
 fun getNodeTemplateProperty(nodeTemplateName: String, propertyId: String): JsonNode {
-    return """{"get_property": ["$nodeTemplateName", "$propertyId"]}""".jsonAsJsonType()
+    return getNodeTemplateProperty(nodeTemplateName, propertyId, null)
 }
 
-fun getNodeTemplateProperty(nodeTemplateName: String, propertyId: String, jsonPath: String): JsonNode {
-    return """{"get_property": ["$nodeTemplateName", "$propertyId", "$jsonPath]}""".jsonAsJsonType()
+fun getNodeTemplateProperty(nodeTemplateName: String, propertyId: String, jsonPath: String?): JsonNode {
+    return if (jsonPath.isNullOrEmpty() || jsonPath.isNullOrBlank()) {
+        """{"get_property": ["$nodeTemplateName", "$propertyId"]}""".jsonAsJsonType()
+    } else {
+        """{"get_property": ["$nodeTemplateName", "$propertyId", "$jsonPath"]}""".jsonAsJsonType()
+    }
 }
 
 // Artifact Function
 
 fun getArtifact(artifactId: String): JsonNode {
-    return """{"get_artifact": ["SELF", "$artifactId"]}""".jsonAsJsonType()
+    return getNodeTemplateArtifact("SELF", artifactId)
 }
 
 fun getNodeTemplateArtifact(nodeTemplateName: String, artifactId: String): JsonNode {
     return """{"get_artifact": ["$nodeTemplateName", "$artifactId"]}""".jsonAsJsonType()
 }
 
+// Operation Function
+
+fun getNodeTemplateOperationOutput(nodeTemplateName: String, interfaceName: String, propertyId: String,
+                                   jsonPath: String? = null): JsonNode {
+    return """{"get_operation_output": ["$nodeTemplateName", "$interfaceName", "process","$propertyId","$jsonPath" ]}""".trimMargin().jsonAsJsonType()
+}
 
 /** Blueprint Type Extensions */
 
diff --git a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintServiceDSLBuilder.kt b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintServiceDSLBuilder.kt
index c9f7d507c..06d3421c0 100644
--- a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintServiceDSLBuilder.kt
+++ b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintServiceDSLBuilder.kt
@@ -17,9 +17,9 @@
 package org.onap.ccsdk.cds.controllerblueprints.core.dsl
 
 import com.fasterxml.jackson.databind.JsonNode
-import org.onap.ccsdk.cds.controllerblueprints.core.BluePrintConstants
-import org.onap.ccsdk.cds.controllerblueprints.core.asJsonType
+import org.onap.ccsdk.cds.controllerblueprints.core.*
 import org.onap.ccsdk.cds.controllerblueprints.core.data.*
+import kotlin.reflect.KClass
 
 class ServiceTemplateBuilder(private val name: String,
                              private val version: String,
@@ -54,6 +54,14 @@ class ServiceTemplateBuilder(private val name: String,
         imports.add(importDefinition)
     }
 
+    fun dsl(id: String, kclass: KClass<*>) {
+        dsl(id, kclass.asPropertyDefinitionMap().asJsonNode())
+    }
+
+    fun dataType(dataType: KClass<*>) {
+        dataType(dataType.asBluePrintsDataTypes())
+    }
+
     fun dsl(id: String, content: Any) {
         dsl(id, content.asJsonType())
     }
diff --git a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintWorkflowDSLBuilder.kt b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintWorkflowDSLBuilder.kt
index f98cf58d3..6d46ac7ad 100644
--- a/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintWorkflowDSLBuilder.kt
+++ b/ms/controllerblueprints/modules/blueprint-core/src/main/kotlin/org/onap/ccsdk/cds/controllerblueprints/core/dsl/BluePrintWorkflowDSLBuilder.kt
@@ -17,10 +17,12 @@
 package org.onap.ccsdk.cds.controllerblueprints.core.dsl
 
 import org.onap.ccsdk.cds.controllerblueprints.core.BluePrintConstants
+import org.onap.ccsdk.cds.controllerblueprints.core.asPropertyDefinitionMap
 import org.onap.ccsdk.cds.controllerblueprints.core.data.Activity
 import org.onap.ccsdk.cds.controllerblueprints.core.data.PropertyDefinition
 import org.onap.ccsdk.cds.controllerblueprints.core.data.Step
 import org.onap.ccsdk.cds.controllerblueprints.core.data.Workflow
+import kotlin.reflect.KClass
 
 class WorkflowBuilder(private val id: String, private val description: String) {
 
@@ -46,6 +48,10 @@ class WorkflowBuilder(private val id: String, private val description: String) {
         steps!![id] = StepBuilder(id, target, description).apply(block).build()
     }
 
+    fun inputs(kClazz: KClass<*>) {
+        inputs = kClazz.asPropertyDefinitionMap()
+    }
+
     fun inputs(block: PropertiesDefinitionBuilder.() -> Unit) {
         inputs = PropertiesDefinitionBuilder().apply(block).build()
     }
@@ -54,6 +60,10 @@ class WorkflowBuilder(private val id: String, private val description: String) {
         outputs = PropertiesDefinitionBuilder().apply(block).build()
     }
 
+    fun outputs(kClazz: KClass<*>) {
+        outputs = kClazz.asPropertyDefinitionMap()
+    }
+
     fun build(): Workflow {
         workflow.id = id
         workflow.description = description