如何从 Python Celery 中的另一个任务触发任务？

Question

# get a list of stuff
@celery.task
def getList():
    listOfStuff = getStuff()
    for thing in listOfStuff:
        processThing.apply_async(args=(thing))


# another attempt at list of stuff
@celery.task
def getList():
    listOfStuff = getStuff()
    for thing in listOfStuff:
        processThing.s((thing))

@celery.task
def processThing(thing):
    pass

So neither getList() implementation triggers the processThing tasks. I can't figure out why. I'm guessing there is a better way of accomplishing what I'm trying to accomplish but I can't figure out what that is.

How can I kick off tasks from another task?

Answer 1

This situation is explained in the docs under http://docs.celeryproject.org/en/latest/userguide/tasks.html#avoid-launching-synchronous-subtasks

Here's a previous thread that shows some code on a similar situation: How to chain a Celery task that returns a list into a group?

Answer 2

celery.execute.send_task("task.fqn", args=[], kwargs={})

这是用来产生任务的命令。

Answer 3

Celery does not require access to a task's code base in order to invoke it. The trick is to invoke a task by its name, either directly via celery_app.send_task(...) or by creating a Signature object celery_app.signature(...) which is the equivalent of calling task.s(...) when you do have access to the task's code base.

more details : https://www.distributedpython.com/2018/06/19/call-celery-task-outside-codebase/