How to check task status in Celery?

How to check task status in Celery?

In Celery, you can check the status of a task using the AsyncResult object returned when you submit a task. The AsyncResult object provides methods to query the status and retrieve the result of the task. Here's how you can check the status of a task in Celery:

  1. Submit a Task:

    First, you need to submit a task to Celery. This can be done using the delay() method or the apply_async() method on a task function. Here's an example of how to submit a task:

    from celery import Celery # Create a Celery instance app = Celery('myapp', broker='pyamqp://guest@localhost//') @app.task def add(x, y): return x + y result = add.delay(4, 5) # Submit a task to add 4 and 5

  2. Check Task Status:

    To check the status of the task, you can use the AsyncResult object's state attribute. The possible states include "PENDING," "STARTED," "SUCCESS," "FAILURE," and others. Here's how to check the status:

    if result.state == 'PENDING': print("Task is pending.") elif result.state == 'STARTED': print("Task is currently running.") elif result.state == 'SUCCESS': print("Task has successfully completed.") result_value = result.result # Get the result of the task elif result.state == 'FAILURE': print("Task has failed.") result_traceback = result.traceback # Get the traceback of the failure

    You can periodically check the task's status in your code or use other mechanisms like callbacks or polling to handle the task's completion.

  3. Retrieve Task Result:

    If the task has completed successfully, you can retrieve its result using the result attribute of the AsyncResult object:

    result_value = result.result # Get the result of the task

    You can also handle task failures and retrieve the traceback if the task has failed:

    if result.state == 'FAILURE': result_traceback = result.traceback # Get the traceback of the failure

Remember that Celery tasks can be executed asynchronously, so it's important to implement proper handling for different task states, especially if you depend on the task's result or need to perform specific actions upon task completion or failure.

Examples

  1. "Checking task status in Celery with TaskAsyncResult"

    Description: Utilize TaskAsyncResult to check the status of a Celery task by its task ID.

    from celery.result import AsyncResult from tasks import task_name # Get task result by task ID task_id = 'your_task_id' result = AsyncResult(task_id) print("Task status:", result.status)

  2. "Monitoring task progress in Celery using task.info"

    Description: Monitor task progress in Celery by accessing task information using .info attribute.

    from tasks import task_name # Get task information task_info = task_name.AsyncResult(task_id).info print("Task info:", task_info)

  3. "Checking task status in Celery with celery.result.AsyncResult"

    Description: Use AsyncResult from celery.result to obtain the status of a Celery task.

    from celery.result import AsyncResult from tasks import task_name # Get task result by task ID task_id = 'your_task_id' result = AsyncResult(task_id) print("Task status:", result.state)

  4. "How to check task completion in Celery with task.ready()"

    Description: Use the ready() method to check if a Celery task has been completed.

    from tasks import task_name # Check if task is ready task_id = 'your_task_id' task_ready = task_name.AsyncResult(task_id).ready() print("Task ready:", task_ready)

  5. "Retrieving task status in Celery using backend result"

    Description: Retrieve task status in Celery using the backend result stored after task execution.

    from celery.result import AsyncResult from celery import current_app # Get task result by task ID task_id = 'your_task_id' backend = current_app.backend result = AsyncResult(task_id, backend=backend) print("Task status:", result.state)

  6. "Checking task status in Celery periodically"

    Description: Periodically check the status of a Celery task using a loop with sleep intervals.

    import time from tasks import task_name task_id = 'your_task_id' while True: result = task_name.AsyncResult(task_id) if result.ready(): print("Task completed:", result.state) break else: print("Task status:", result.state) time.sleep(5) # Adjust sleep interval as needed

  7. "Getting task status updates in Celery with on_success/on_failure callbacks"

    Description: Use on_success and on_failure callbacks to receive task status updates in Celery.

    from celery import Celery app = Celery('tasks', backend='redis://localhost', broker='redis://localhost') @app.task def your_task(): print("Task completed successfully") def on_success_callback(task_id, task_result): print("Task status:", task_result.state) def on_failure_callback(task_id, exception): print("Task failed:", exception) task_result = your_task.apply_async(on_success=on_success_callback, on_failure=on_failure_callback)

  8. "Using celery.result.AsyncResult to check task status in Celery"

    Description: Utilize AsyncResult from celery.result to access task status in Celery.

    from celery.result import AsyncResult from tasks import task_name # Get task result by task ID task_id = 'your_task_id' result = AsyncResult(task_id) print("Task status:", result.state)

  9. "How to monitor Celery task status using celery.result.AsyncResult"

    Description: Monitor Celery task status by using AsyncResult from celery.result.

    from celery.result import AsyncResult from tasks import task_name # Get task result by task ID task_id = 'your_task_id' result = AsyncResult(task_id) print("Task status:", result.state)

  10. "Checking Celery task status with task.AsyncResult"

    Description: Check the status of a Celery task using AsyncResult from the task itself.

    from tasks import task_name # Get task result by task ID task_id = 'your_task_id' result = task_name.AsyncResult(task_id) print("Task status:", result.state)

More Tags

ora-01036 azure-blob-storage viewport-units ssis image-recognition cassandra-cli rolling-sum undo mouse seaborn

More Python Questions

More Chemical reactions Calculators

More Statistics Calculators

More Livestock Calculators

More Chemical thermodynamics Calculators