celery: how to rename a task and route it to a queue

Question

Could you please advise on how to assign a custom name on a celery task ? By default, it gets the module name, but I was wondering in case I would like to send a task to a specific queue, how I can achieve that ?

In other words,

given that the related Celery config is like:

CELERY_QUEUES = (
    Queue('celery.A', Exchange("xxx"), routing_key='celery.A'),
    Queue('celery.B', Exchange("xxx"), routing_key='celery.B'),
)
CELERY_ROUTES = {
    'A': {'queue': 'celery.A', 'routing_key': 'celery.A'},
    'B': {'queue': 'celery.B', 'routing_key': 'celery.B'},
}

and there is a function:

@app.task(ignore_result=True)
def xxx(netelement):
    pass

What I would like to achieve is: if netelement == A do task.name=A (and then, according to the mapping, route it to queue A)

Is that possible ?

Answer 1

You can't change the routing in the function body because by definition the task is already executing and has already been routed.

The one obvious solution I can think of is to have your first task delegate to another (asynchronously so it can get routed appropriately).

@app.task(ignore_result=True)
def xxx(netelement):
    if netelement == A:
       task_A.delay()
    else:
       task_B.delay()