CODEWITHSUNDEEP
djangorabbitmqcelery
Nishad Wadwekar
Nishad Wadwekar

Reputation: 98

Unable to Start Celery worker instance : Syntax error

I am trying to run a task in django view asynchronously. For that i am using celery and rabbitmq. By following the guide for small scale context i have defined task in my module(servicenow.py) as - 

app = Celery('servicenow',broker='amqp://username:password@localhost:15672')
.
.
@app.task
def get_ITARAS_dump(self):
.
.
self.update_state(state='PROGRESS',meta={'current':i,'total':len(taskList)})

My rabbitmq server is running within brew services

Rabbitmq management on safari

After this i tried to start a worker instance with celery -A servicenow worker -l info then i the error message as - 

Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.7/bin/celery", line 11, in <module>
    sys.exit(main())
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/__main__.py", line 30, in main
    main()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/bin/celery.py", line 81, in main
    cmd.execute_from_commandline(argv)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/bin/celery.py", line 793, in execute_from_commandline
    super(CeleryCommand, self).execute_from_commandline(argv)))
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/bin/base.py", line 311, in execute_from_commandline
    return self.handle_argv(self.prog_name, argv[1:])
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/bin/celery.py", line 785, in handle_argv
    return self.execute(command, argv)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/bin/celery.py", line 717, in execute
    ).run_from_argv(self.prog_name, argv[1:], command=argv[0])
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/bin/worker.py", line 179, in run_from_argv
    return self(*args, **options)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/bin/base.py", line 274, in __call__
    ret = self.run(*args, **kwargs)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/bin/worker.py", line 194, in run
    pool_cls = (concurrency.get_implementation(pool_cls) or
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/concurrency/__init__.py", line 29, in get_implementation
    return symbol_by_name(cls, ALIASES)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/kombu/utils/__init__.py", line 96, in symbol_by_name
    module = imp(module_name, package=package, **kwargs)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
  File "<frozen importlib._bootstrap>", line 983, in _find_and_load
  File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 728, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/concurrency/prefork.py", line 20, in <module>
    from celery.concurrency.base import BasePool
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/concurrency/base.py", line 21, in <module>
    from celery.utils import timer2
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/celery/utils/timer2.py", line 19
    from kombu.async.timer import Entry, Timer as Schedule, to_timestamp, logger
                   ^
SyntaxError: invalid syntax

I think this is a version issue but according to requirements i think i have it correct

django-celery==3.2.2
  - celery [required: >=3.1.15,<4.0, installed: 3.1.26.post2]
    - billiard [required: >=3.3.0.23,<3.4, installed: 3.3.0.23]
    - kombu [required: >=3.0.37,<3.1, installed: 3.0.37]
      - amqp [required: >=1.4.9,<2.0, installed: 1.4.9]
      - anyjson [required: >=0.3.3, installed: 0.3.3]
    - pytz [required: >dev, installed: 2018.7]
  - django [required: >=1.8, installed: 2.1.3]
    - pytz [required: Any, installed: 2018.7]

Please help, I cannot figure if i am missing a step in configuration or version issue. Also, if someone can verify these steps are correct in order to perform a async task on module level with celery. Thanks!

Upvotes: 0

Views: 4539

Answers (3)

Shivam Kohli
Shivam Kohli

Reputation: 489

The issue is because you are using python 3.7. Downgrading it to python 3.6 will solve the error. For mac user to downgrade to python 3.6

$ brew unlink python
$ brew install --ignore-dependencies https://raw.githubusercontent.com/Homebrew/homebrew-core/e128fa1bce3377de32cbf11bd8e46f7334dfd7a6/Formula/python.rb
$ brew switch python 3.6.5

Upvotes: 0

jmoz
jmoz

Reputation: 8006

There's a conflict on the result backend code. Quick fix is to disable the result backed setting, e.g.

# CELERY_RESULT_BACKEND = 'redis://redis'

Upvotes: 1

ruddra
ruddra

Reputation: 51988

Well, its a known issue for Celery. Celery does not support python 3.7 yet. Same goes to Kombu. So downgrade python to 3.6 or former. You can check the status of that issue at https://github.com/celery/celery/issues/4500

Upvotes: 5

Related Questions