"""Celery execution engine integration.
This module provides a Celery-based execution engine for distributed workflow
execution. Celery is a distributed task queue that supports multiple message
brokers (Redis, RabbitMQ, etc.).
Installation:
.. code-block:: bash
pip install litestar-workflows[celery]
Note:
This integration is planned for Phase 6 (v0.7.0) and is currently a stub.
See PLAN.md for the implementation roadmap.
Example (planned API):
.. code-block:: python
from celery import Celery
from litestar_workflows.contrib.celery import CeleryExecutionEngine
celery_app = Celery("workflows", broker="redis://localhost:6379/0")
engine = CeleryExecutionEngine(
celery_app=celery_app,
registry=workflow_registry,
persistence=workflow_persistence,
)
# Steps execute as Celery tasks
instance = await engine.start_workflow(ApprovalWorkflow, initial_data={...})
"""
from __future__ import annotations
__all__ = ["CeleryExecutionEngine"]
[docs]
class CeleryExecutionEngine: # pragma: no cover
"""Celery-based distributed execution engine (stub).
This engine delegates step execution to Celery workers, enabling horizontal
scaling of workflow execution across multiple machines.
Note:
This is a stub implementation. The actual implementation is planned
for Phase 6 (v0.7.0).
Raises:
NotImplementedError: Always raised as this is a stub.
"""
[docs]
def __init__(self, *args: object, **kwargs: object) -> None:
"""Initialize CeleryExecutionEngine.
Raises:
NotImplementedError: This is a stub implementation.
"""
msg = (
"CeleryExecutionEngine is not yet implemented. "
"This feature is planned for Phase 6 (v0.7.0). "
"See PLAN.md for the implementation roadmap."
)
raise NotImplementedError(msg)