docs(ingest): script to add ERModelRelationship Entity (datahub-proje…

…ct#12473)

metadata-ingestion/examples/library/create_ermodelrelationship.py

@@ -0,0 +1,134 @@
+import time
+
+from datahub.emitter.mce_builder import make_data_platform_urn, make_dataset_urn
+from datahub.emitter.mcp import MetadataChangeProposalWrapper
+from datahub.emitter.rest_emitter import DatahubRestEmitter
+from datahub.metadata.schema_classes import (
+    AuditStampClass,
+    ERModelRelationshipCardinalityClass,
+    ERModelRelationshipKeyClass,
+    ERModelRelationshipPropertiesClass,
+    NumberTypeClass,
+    OtherSchemaClass,
+    RelationshipFieldMappingClass,
+    SchemaFieldClass,
+    SchemaFieldDataTypeClass,
+    SchemaMetadataClass,
+    StringTypeClass,
+)
+
+# Configuration
+GMS_ENDPOINT = "http://localhost:8080"
+PLATFORM = "mysql"
+ENV = "PROD"
+
+e = DatahubRestEmitter(gms_server=GMS_ENDPOINT, extra_headers={})
+
+
+def get_schema_field(
+    name: str, dtype: str, type: SchemaFieldDataTypeClass
+) -> SchemaFieldClass:
+    """Creates a schema field for MySQL columns."""
+
+    field = SchemaFieldClass(
+        fieldPath=name,
+        type=type,
+        nativeDataType=dtype,
+        description=name,
+        lastModified=AuditStampClass(
+            time=int(time.time() * 1000),
+            actor="urn:li:corpuser:ingestion",
+        ),
+    )
+    if name == "id":
+        field.isPartitioningKey = True
+    return field
+
+
+# Define Employee Table
+dataset_employee = make_dataset_urn(PLATFORM, "Employee", ENV)
+employee_fields = [
+    get_schema_field("id", "int", SchemaFieldDataTypeClass(type=NumberTypeClass())),
+    get_schema_field(
+        "name", "varchar", SchemaFieldDataTypeClass(type=StringTypeClass())
+    ),
+    get_schema_field("age", "int", SchemaFieldDataTypeClass(type=NumberTypeClass())),
+    get_schema_field(
+        "company_id", "int", SchemaFieldDataTypeClass(type=NumberTypeClass())
+    ),
+]
+
+e.emit_mcp(
+    MetadataChangeProposalWrapper(
+        entityUrn=dataset_employee,
+        aspect=SchemaMetadataClass(
+            schemaName="Employee",
+            platform=make_data_platform_urn(PLATFORM),
+            fields=employee_fields,
+            version=0,
+            hash="",
+            platformSchema=OtherSchemaClass(rawSchema=""),
+        ),
+    )
+)
+
+# Define Company Table
+dataset_company = make_dataset_urn(PLATFORM, "Company", ENV)
+company_fields = [
+    get_schema_field("id", "int", SchemaFieldDataTypeClass(type=NumberTypeClass())),
+    get_schema_field(
+        "name", "varchar", SchemaFieldDataTypeClass(type=StringTypeClass())
+    ),
+]
+
+e.emit_mcp(
+    MetadataChangeProposalWrapper(
+        entityUrn=dataset_company,
+        aspect=SchemaMetadataClass(
+            schemaName="Company",
+            platform=make_data_platform_urn(PLATFORM),
+            fields=company_fields,
+            version=0,
+            hash="",
+            platformSchema=OtherSchemaClass(rawSchema=""),
+        ),
+    )
+)
+
+# Establish Relationship (Foreign Key: Employee.company_id → Company.id)
+relationship_key = ERModelRelationshipKeyClass(id="employee_to_company")
+relationship_properties = ERModelRelationshipPropertiesClass(
+    name="Employee to Company Relationship",
+    source=dataset_employee,
+    destination=dataset_company,
+    relationshipFieldMappings=[
+        RelationshipFieldMappingClass(sourceField="company_id", destinationField="id")
+    ],
+    cardinality=ERModelRelationshipCardinalityClass.N_ONE,
+    customProperties={"constraint": "Foreign Key", "index": "company_id"},
+)
+
+relationship_urn = f"urn:li:erModelRelationship:{relationship_key.id}"
+
+e.emit_mcp(
+    MetadataChangeProposalWrapper(
+        entityType="erModelRelationship",
+        changeType="UPSERT",
+        entityKeyAspect=relationship_key,
+        aspectName=relationship_key.ASPECT_NAME,
+        aspect=relationship_key,
+    )
+)
+
+e.emit_mcp(
+    MetadataChangeProposalWrapper(
+        entityUrn=relationship_urn,
+        entityType="erModelRelationship",
+        changeType="UPSERT",
+        aspectName=relationship_properties.ASPECT_NAME,
+        aspect=relationship_properties,
+    )
+)
+
+print("relationship_urn", relationship_urn)
+print("Employee and Company tables created with ERModelRelationship linking them.")