Celery 'module' object has no attribute 'app' when using Python 3

Question

I am going through Celery tutorial. They are using Python2 and I am trying to implement the same using python3.

I have 2 files:

celery_proj.py :

from celery import Celery

app = Celery(
    'proj', broker='amqp://', backend='amqp://', include=['proj.tasks'])

app.conf.update(Celery_TAST_RESULT_EXPIRES=3600,)

if __name__ == '__main__':
    app.start()

and tasks.py :

from celery_proj import app


@app.task
def add(x, y):
    return x + y


@app.task
def mul(x, y):
    return x * y


@app.task
def xsum(numbers):
    return sum(numbers)

When I try to run celery -A proj worker -l info I am getting :

Traceback (most recent call last):
  File "/usr/local/lib/python3.4/dist-packages/celery/app/utils.py", line 235, in find_app
    found = sym.app
AttributeError: 'module' object has no attribute 'app'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/bin/celery", line 11, in <module>
    sys.exit(main())
  File "/usr/local/lib/python3.4/dist-packages/celery/__main__.py", line 30, in main
    main()
  File "/usr/local/lib/python3.4/dist-packages/celery/bin/celery.py", line 81, in main
    cmd.execute_from_commandline(argv)
  File "/usr/local/lib/python3.4/dist-packages/celery/bin/celery.py", line 769, in execute_from_commandline
    super(CeleryCommand, self).execute_from_commandline(argv)))
  File "/usr/local/lib/python3.4/dist-packages/celery/bin/base.py", line 309, in execute_from_commandline
    argv = self.setup_app_from_commandline(argv)
  File "/usr/local/lib/python3.4/dist-packages/celery/bin/base.py", line 469, in setup_app_from_commandline
    self.app = self.find_app(app)
  File "/usr/local/lib/python3.4/dist-packages/celery/bin/base.py", line 489, in find_app
    return find_app(app, symbol_by_name=self.symbol_by_name)
  File "/usr/local/lib/python3.4/dist-packages/celery/app/utils.py", line 240, in find_app
    found = sym.celery
AttributeError: 'module' object has no attribute 'celery'

What am I doing wrong and how to fix this?

Answer 1

When you run Celery with celery -A proj worker

AttributeError: 'module' object has no attribute 'app'
...
AttributeError: 'module' object has no attribute 'celery'

tell you that it tries to find:

a) app instance

b) proj.celery module

So you can either add from celery_proj import app to __init__.py or rename your celery_proj.py to celery.py.

Or you can run Celery as celery -A proj.celery_proj worker

I found the answer here as no answer here on stackoverflow had helped me.