Why does Celery work in Python shell, but not in my Django views? (import problem)

Question

I installed Celery (latest stable version.) I have a directory called /home/myuser/fable/jobs. Inside this directory, I have a file called tasks.py:

from celery.decorators import task
from celery.task import Task

class Submitter(Task):
    def run(self, post, **kwargs):
        return "Yes, it works!!!!!!"

Inside this directory, I also have a file called celeryconfig.py:

BROKER_HOST = "localhost"
BROKER_PORT = 5672
BROKER_USER = "abc"
BROKER_PASSWORD = "xyz"
BROKER_VHOST = "fablemq"

CELERY_RESULT_BACKEND = "amqp"
CELERY_IMPORTS = ("tasks", )

In my /etc/profile, I have these set as my PYTHONPATH:

• PYTHONPATH=/home/myuser/fable:/home/myuser/fable/jobs

So I run my Celery worker using the console ($ celeryd --loglevel=INFO), and I try it out. I open the Python console and import the tasks. Then, I run the Submitter.

>>> import fable.jobs.tasks as tasks
>>> s = tasks.Submitter()
>>> s.delay("abc")
<AsyncResult: d70d9732-fb07-4cca-82be-d7912124a987>

Everything works, as you can see in my console

[2011-01-09 17:30:05,766: INFO/MainProcess] Task tasks.Submitter[d70d9732-fb07-4cca-82be-d7912124a987] succeeded in 0.0398268699646s:

But when I go into my Django's views.py and run the exact 3 lines of code as above, I get this:

[2011-01-09 17:25:20,298: ERROR/MainProcess] Unknown task ignored: "Task of kind 'fable.jobs.tasks.Submitter' is not registered, please make sure it's imported.": {'retries': 0, 'task': 'fable.jobs.tasks.Submitter', 'args': ('abc',), 'expires': None, 'eta': None, 'kwargs': {}, 'id': 'eb5c65b4-f352-45c6-96f1-05d3a5329d53'}
Traceback (most recent call last):
  File "/home/myuser/mysite-env/lib/python2.6/site-packages/celery/worker/listener.py", line 321, in receive_message
    eventer=self.event_dispatcher)
  File "/home/myuser/mysite-env/lib/python2.6/site-packages/celery/worker/job.py", line 299, in from_message
    eta=eta, expires=expires)
  File "/home/myuser/mysite-env/lib/python2.6/site-packages/celery/worker/job.py", line 243, in __init__
    self.task = tasks[self.task_name]
  File "/home/myuser/mysite-env/lib/python2.6/site-packages/celery/registry.py", line 63, in __getitem__
    raise self.NotRegistered(str(exc))
NotRegistered: "Task of kind 'fable.jobs.tasks.Submitter' is not registered, please make sure it's imported."

It's weird, because the celeryd client does show that it's registered, when I launch it.

[2011-01-09 17:38:27,446: WARNING/MainProcess]  
Configuration ->
    . broker -> amqp://GOGOme@localhost:5672/fablemq
    . queues ->
        . celery -> exchange:celery (direct) binding:celery
    . concurrency -> 1
    . loader -> celery.loaders.default.Loader
    . logfile -> [stderr]@INFO
    . events -> OFF
    . beat -> OFF
    . tasks ->
        . tasks.Decayer
        . tasks.Submitter

Can someone help?

Answer 1

This is what I did which finally worked

in Settings.py I added

CELERY_IMPORTS = ("myapp.jobs", )

under myapp folder I created a file called jobs.py

from celery.decorators import task

@task(name="jobs.add")
def add(x, y):
    return x * y

Then ran from commandline: python manage.py celeryd -l info

in another shell i ran python manage.py shell, then

>>> from myapp.jobs import add
>>> result = add.delay(4, 4)
>>> result.result

and the i get:

16

The important point is that you have to rerun both command shells when you add a new function. You have to register the name both on the client and and on the server.

:-)

Answer 2

I believe your tasks.py file needs to be in a django app (that's registered in settings.py) in order to be imported. Alternatively, you might try importing the tasks from an __init__.py file in your main project or one of the apps.

Also try starting celeryd from manage.py:

$ python manage.py celeryd -E -B -lDEBUG

(-E and -B may or may not be necessary, but that's what I use).