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Domain Event

Description​

Represents a significant occurrence in the domain. Domain Events are facts about things that have happened.

Definition Schema​

The definition for a domain_event component expects the following structure:

{
  "$defs": {
    "EventParameterInputDTO": {
      "description": "Generic DTO for defining a parameter (field) in a generated event class.",
      "example": {
        "default_value_str": null,
        "param_name": "user_id",
        "param_type_str": "int"
      },
      "properties": {
        "param_name": {
          "title": "Param Name",
          "type": "string"
        },
        "param_type_str": {
          "title": "Param Type Str",
          "type": "string"
        },
        "default_value_str": {
          "anyOf": [
            {
              "type": "string"
            },
            {
              "type": "null"
            }
          ],
          "default": null,
          "title": "Default Value Str"
        }
      },
      "required": [
        "param_name",
        "param_type_str"
      ],
      "title": "EventParameterInputDTO",
      "type": "object"
    }
  },
  "description": "DTO for defining an event class.",
  "example": {
    "event_name": "UserCreated",
    "parameters": [
      {
        "param_name": "user_id",
        "param_type_str": "int"
      },
      {
        "param_name": "username",
        "param_type_str": "str"
      },
      {
        "param_name": "created_at",
        "param_type_str": "datetime"
      }
    ]
  },
  "properties": {
    "name": {
      "title": "Name",
      "type": "string"
    },
    "parameters": {
      "items": {
        "$ref": "#/$defs/EventParameterInputDTO"
      },
      "title": "Parameters",
      "type": "array"
    }
  },
  "required": [
    "name"
  ],
  "title": "EventInputDTO",
  "type": "object"
}

Naming and Location Conventions​

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

Example Definition​

{
  "event_name": "UserCreated",
  "parameters": [
    {
      "param_name": "user_id",
      "param_type_str": "int"
    },
    {
      "param_name": "username",
      "param_type_str": "str"
    },
    {
      "param_name": "created_at",
      "param_type_str": "datetime"
    }
  ]
}