Can a Celery task's definition and implementation be split?

Question

I'm using Celery in Python to run background tasks and couldn't find any definitive answer to the question of whether I can split the Celery task definition from task implementation?

For example, take the really simple task below:

@celery_app.task
def add_numbers(num1, num2):
    return num1 + num2

The definition and implementation are in the same file i.e. when the caller imports this module to call add_numbers, both the definition and implementation are imported.

In this case, not so bad. But my tasks are a bit more complex, importing multiple modules and packages that the caller certainly doesn't need and I'd like to keep out of the caller.

So, does Celery provide a way to do this? Or am I going against the framework? Is this even a problem?

I have seen this question Celery dynamic tasks / hiding Celery implementation behind an interface implementation-behind-an-interface, but it is well over two years old - more than enough time for a lot to change.

Answer 1

There's a feature called signatures which allows calling tasks without importing them. You will need the Celery app instance to be available:

sig = celery_app.signature('myapp.add_numbers', args=(1,2))
sig.delay()