Add saga id for step result

Author: Вадим Козыревский

src/cqrs/saga/saga.py

@@ -1,3 +1,4 @@
+import dataclasses
 import logging
 import types
 import typing
@@ -278,7 +279,10 @@ async def __aiter__(
                     if step_result is not None and executed_step is not None:
                         # Track completed step for compensation
                         self._completed_steps.append(executed_step)
-                        yield step_result
+                        yield dataclasses.replace(
+                            step_result,
+                            saga_id=self._saga_id,
+                        )
                     elif executed_step is None:
                         # Step was skipped (already completed), restore it for compensation
                         primary_name = step_item.step.__name__
@@ -313,7 +317,10 @@ async def __aiter__(
                 step = await self._container.resolve(step_type)
                 self._completed_steps.append(step)
 
-                yield step_result
+                yield dataclasses.replace(
+                    step_result,
+                    saga_id=self._saga_id,
+                )
 
             # Update context one final time before marking as completed
             await self._state_manager.update_context(self._context)

src/cqrs/saga/step.py

@@ -3,6 +3,7 @@
 import abc
 import dataclasses
 import typing
+import uuid
 
 from cqrs.events.event import IEvent
 from cqrs.response import IResponse
@@ -17,8 +18,6 @@ class SagaStepResult(typing.Generic[ContextT, Resp]):
     Result of a saga step execution.
 
     Contains the response from the step's act method and metadata about the step.
-    The step_type field uses typing.Any for compatibility,
-    but the actual runtime type is Type[SagaStepHandler[ContextT, Resp]].
 
     This is an internal data structure used by the saga pattern implementation.
 
@@ -29,6 +28,8 @@ class SagaStepResult(typing.Generic[ContextT, Resp]):
         error_message: Error message if with_error is True
         error_traceback: Error traceback lines if with_error is True
         error_type: Type of exception if with_error is True
+        saga_id: ID of the saga this step belongs to (set by execution layer).
+                 Enables client code to trigger compensation immediately if the saga fails.
 
     Example::
 
@@ -40,11 +41,12 @@ class SagaStepResult(typing.Generic[ContextT, Resp]):
     """
 
     response: Resp
-    step_type: typing.Any  # type: ignore[assignment]  # Actual type: Type[SagaStepHandler[ContextT, Resp]]
+    step_type: type[SagaStepHandler[ContextT, Resp]]
     with_error: bool = False
     error_message: str | None = None
     error_traceback: list[str] | None = None
     error_type: typing.Type[Exception] | None = None
+    saga_id: uuid.UUID | None = None
 
 
 class SagaStepHandler(abc.ABC, typing.Generic[ContextT, Resp]):

tests/unit/test_saga/test_saga_basic.py

@@ -313,3 +313,4 @@ async def test_saga_step_result_contains_correct_metadata(
         assert step_result.error_message is None
         assert step_result.error_traceback is None
         assert step_result.error_type is None
+        assert step_result.saga_id is not None