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Domain Service

Description​

Encapsulates domain logic that doesn't naturally fit within an Entity or Value Object. Often orchestrates operations across multiple domain objects.

Definition Schema​

The definition for a domain_service component expects the following structure:

{
  "$defs": {
    "ServiceDependencyInputDTO": {
      "description": "Defines a dependency to be injected into the Service's __init__.",
      "example": {
        "assigned_attribute_name": "_emailer",
        "param_name": "email_service",
        "param_type_str": "EmailService"
      },
      "example_with_explicit_import": {
        "param_import_from_module": "sqlalchemy.ext.asyncio",
        "param_import_names": [
          "AsyncSession"
        ],
        "param_name": "async_session_factory",
        "param_type_str": "AsyncSession"
      },
      "properties": {
        "param_name": {
          "description": "Name of the parameter in __init__ (e.g., 'user_repository')",
          "title": "Param Name",
          "type": "string"
        },
        "param_type_str": {
          "description": "Type hint string for the parameter (e.g., 'UserRepository')",
          "title": "Param Type Str",
          "type": "string"
        },
        "assigned_attribute_name": {
          "anyOf": [
            {
              "type": "string"
            },
            {
              "type": "null"
            }
          ],
          "default": null,
          "description": "Name of the attribute to assign the dependency to on self (e.g., '_repo'). Defaults to '_' + param_name if None.",
          "title": "Assigned Attribute Name"
        },
        "param_import_from_module": {
          "anyOf": [
            {
              "type": "string"
            },
            {
              "type": "null"
            }
          ],
          "default": null,
          "description": "Optional: Explicit module to import the dependency type from (e.g., 'sqlalchemy.ext.asyncio').",
          "title": "Param Import From Module"
        },
        "param_import_names": {
          "anyOf": [
            {
              "items": {
                "type": "string"
              },
              "type": "array"
            },
            {
              "type": "null"
            }
          ],
          "default": null,
          "description": "Optional: Explicit list of names to import from the module (e.g., ['AsyncSession']). Used if param_import_from_module is set.",
          "title": "Param Import Names"
        }
      },
      "required": [
        "param_name",
        "param_type_str"
      ],
      "title": "ServiceDependencyInputDTO",
      "type": "object"
    }
  },
  "description": "DTO for defining a Domain Service class within a Bounded Context.",
  "example": {
    "bounded_context_name": "ordering",
    "dependencies": [],
    "name": "OrderProcessingService"
  },
  "properties": {
    "name": {
      "description": "Name of the service class (e.g., 'UserManagementService')",
      "title": "Name",
      "type": "string"
    },
    "dependencies": {
      "description": "List of dependencies for the __init__ method.",
      "items": {
        "$ref": "#/$defs/ServiceDependencyInputDTO"
      },
      "title": "Dependencies",
      "type": "array"
    },
    "bounded_context_name": {
      "description": "Name of the Bounded Context",
      "title": "Bounded Context Name",
      "type": "string"
    }
  },
  "required": [
    "name",
    "bounded_context_name"
  ],
  "title": "DomainServiceInputDTO",
  "type": "object"
}

Naming and Location Conventions​

Class: PascalCase, typically ends with 'Service'. File: ${domain_service_name}.py (based on ${domain_service_name}). Location: app/domain/${bounded_ctx}/services. (Requires context: ['bounded_ctx'])

Example Definition​

{
  "name": "OrderProcessingService",
  "bounded_context_name": "ordering",
  "dependencies": []
}