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Shared Aggregate

Description​

An Aggregate that is part of the Shared Kernel, common to multiple Bounded Contexts.

Definition Schema​

The definition for a shared_aggregate component expects the following structure:

{
  "$defs": {
    "AggregateCreationParameterInputDTO": {
      "description": "Defines a parameter for the initiate_creation class method.",
      "example": {
        "param_name": "title",
        "param_type_str": "str"
      },
      "properties": {
        "param_name": {
          "title": "Param Name",
          "type": "string"
        },
        "param_type_str": {
          "title": "Param Type Str",
          "type": "string"
        }
      },
      "required": [
        "param_name",
        "param_type_str"
      ],
      "title": "AggregateCreationParameterInputDTO",
      "type": "object"
    },
    "AggregateCreationParameterOutput": {
      "properties": {
        "param_name": {
          "title": "Param Name",
          "type": "string"
        },
        "param_type_str": {
          "title": "Param Type Str",
          "type": "string"
        }
      },
      "required": [
        "param_name",
        "param_type_str"
      ],
      "title": "AggregateCreationParameterOutput",
      "type": "object"
    },
    "AggregateStateParameterInputDTO": {
      "description": "Defines a state field within the aggregate.",
      "example": {
        "param_name": "title",
        "param_type_str": "str"
      },
      "properties": {
        "param_name": {
          "title": "Param Name",
          "type": "string"
        },
        "param_type_str": {
          "title": "Param Type Str",
          "type": "string"
        }
      },
      "required": [
        "param_name",
        "param_type_str"
      ],
      "title": "AggregateStateParameterInputDTO",
      "type": "object"
    },
    "AggregateStateParameterOutput": {
      "properties": {
        "param_name": {
          "title": "Param Name",
          "type": "string"
        },
        "param_type_str": {
          "title": "Param Type Str",
          "type": "string"
        }
      },
      "required": [
        "param_name",
        "param_type_str"
      ],
      "title": "AggregateStateParameterOutput",
      "type": "object"
    }
  },
  "description": "Input DTO specifically for the AggregateCodeEngine.",
  "example": {
    "created_event_module": "app_root_name.domain.ordering.events",
    "created_event_name": "OrderCreatedEvent",
    "creation_parameters": [
      {
        "param_name": "customer_id",
        "param_type_str": "int"
      }
    ],
    "id_generation_logic_str": "None # Assuming DB generates ID",
    "id_type_str": "int",
    "name": "OrderAggregate",
    "state_parameters": [
      {
        "param_name": "status",
        "param_type_str": "str"
      },
      {
        "param_name": "total_amount",
        "param_type_str": "Decimal"
      }
    ]
  },
  "properties": {
    "name": {
      "title": "Name",
      "type": "string"
    },
    "id_type_str": {
      "title": "Id Type Str",
      "type": "string"
    },
    "state_parameters": {
      "items": {
        "anyOf": [
          {
            "$ref": "#/$defs/AggregateStateParameterInputDTO"
          },
          {
            "$ref": "#/$defs/AggregateStateParameterOutput"
          }
        ]
      },
      "title": "State Parameters",
      "type": "array"
    },
    "creation_parameters": {
      "items": {
        "anyOf": [
          {
            "$ref": "#/$defs/AggregateCreationParameterInputDTO"
          },
          {
            "$ref": "#/$defs/AggregateCreationParameterOutput"
          }
        ]
      },
      "title": "Creation Parameters",
      "type": "array"
    },
    "created_event_name": {
      "title": "Created Event Name",
      "type": "string"
    },
    "created_event_module": {
      "title": "Created Event Module",
      "type": "string"
    },
    "id_generation_logic_str": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "null"
        }
      ],
      "default": "uuid.uuid4()",
      "title": "Id Generation Logic Str"
    }
  },
  "required": [
    "name",
    "id_type_str",
    "created_event_name",
    "created_event_module"
  ],
  "title": "AggregateEngineInputDTO",
  "type": "object"
}

Naming and Location Conventions​

Class: PascalCase, typically ends with 'Aggregate'. File: ${shared_aggregate_name}.py (based on ${shared_aggregate_name}). Location: app/domain/shared_kernel/aggregates.

Example Definition​

{
  "name": "OrderAggregate",
  "id_type_str": "int",
  "state_parameters": [
    {
      "param_name": "status",
      "param_type_str": "str"
    },
    {
      "param_name": "total_amount",
      "param_type_str": "Decimal"
    }
  ],
  "creation_parameters": [
    {
      "param_name": "customer_id",
      "param_type_str": "int"
    }
  ],
  "created_event_name": "OrderCreatedEvent",
  "created_event_module": "app_root_name.domain.ordering.events",
  "id_generation_logic_str": "None # Assuming DB generates ID"
}