为什么Celery只识别来自单个Django应用的任务

Question

So we have this Django project with multiple apps, and we use celery for tasks. The issue we are running into is that only the tasks inside the tasks.py of a single app will run, other tasks.py tasks in other apps return the following error:

celery_1     | [2018-10-22 08:27:59,563: ERROR/MainProcess] Received unregistered task of type 'biko.supplier.tasks.test_task'.
celery_1     | The message has been ignored and discarded.
celery_1     |
celery_1     | Did you remember to import the module containing this task?
celery_1     | Or maybe you're using relative imports?
celery_1     |
celery_1     | Please see
celery_1     | http://docs.celeryq.org/en/latest/internals/protocol.html
celery_1     | for more information.
celery_1     |
celery_1     | The full contents of the message body was:
celery_1     | b'[[], {}, {"callbacks": null, "errbacks": null, "chain": null, "chord": null}]' (77b)
celery_1     | Traceback (most recent call last):
celery_1     |   File "/usr/local/lib/python3.6/site-packages/celery/worker/consumer/consumer.py", line 557, in on_task_received
celery_1     |     strategy = strategies[type_]
celery_1     | KeyError: 'biko.supplier.tasks.test_task'

This happens when I run test_task.delay()

Here is the supplier tasks.py:

from config.celery import app

@app.task(shared=True)
def test_task():
    print("Runnign this task correctly")

Here is the a part of the shop tasks.py, where the tasks do work correctly:

from django.contrib.contenttypes.models import ContentType

from config.celery import app
from celery_once import QueueOnce
from django.core.management import call_command
from django.utils import timezone
from raven.contrib.django.raven_compat.models import client

from biko.shop.models import Shop
from config.settings import MAX_INCOMING_BUFFER_RETRIES
from biko.buffer.models import IncomingBuffer, OutgoingBuffer

@app.task(shared=True)
def buffer_products(shop_id):
    shop = Shop.objects.get(id=shop_id)
    shop.get_manager().buffer_products()

And here is the celery config:

import os

from celery import Celery
from celery.schedules import crontab
from django.conf import settings

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "config.settings")

app = Celery('biko')

app.config_from_object('django.conf:settings')

app.autodiscover_tasks()
app.conf.ONCE = {
  'backend': 'celery_once.backends.Redis',
  'settings': {
    'url': 'redis://redis',
    'blocking': True,
    'default_timeout': 60 * 60,
    'blocking_timeout': 86400
  }
}

Any task not part of shop/tasks.py is not shown as being loaded. I have no clue as to why it would load tasks from shop/tasks.py but not from another app.

Answer 1

In Celery config; You can do the following:

# Where app_module represents where tasks exists.
app = Celery('biko', include=['app_module.tasks'])

# Your line should also work, but sometimes it needs the apps configs
app.autodiscover_tasks(lambda: settings.INSTALLED_APPS)