Setup logging of Celery in Django correctly - how? - django

Question

Setting up celery on our production server seems to be more complicated than it should be - and the problem is logging.
Our setup is like this:
Server is Ubuntu 20.04.5 LTS
We run Django 3.2.8 in it's own user and group named "django"
The Celery process also has it's own user and group named "celery".
Celery is set up as a service and logs to /var/log/celery
In celery.py we have set djangoConf pointing to the main settings.py
On startup Celery tries to touch a django-logfile and - missing the permissions to do so - returns an error:
Dec 16 10:57:27 h2989788 celery[128418]: Usage: celery [OPTIONS] COMMAND [ARGS]...
Dec 16 10:57:27 h2989788 celery[128418]: Try 'celery --help' for help.
Dec 16 10:57:27 h2989788 celery[128418]: Error: Invalid value for '-A' / '--app':
Dec 16 10:57:27 h2989788 celery[128418]: Unable to load celery application.
Dec 16 10:57:27 h2989788 celery[128418]: While trying to load the module theApp the following error occurred:
Dec 16 10:57:27 h2989788 celery[128418]: Traceback (most recent call last):
Dec 16 10:57:27 h2989788 celery[128418]: File "/usr/lib/python3.8/logging/config.py", line 563, in configure
Dec 16 10:57:27 h2989788 celery[128418]: handler = self.configure_handler(handlers[name])
Dec 16 10:57:27 h2989788 celery[128418]: File "/usr/lib/python3.8/logging/config.py", line 744, in configure_handler
Dec 16 10:57:27 h2989788 celery[128418]: result = factory(**kwargs)
Dec 16 10:57:27 h2989788 celery[128418]: File "/usr/lib/python3.8/logging/handlers.py", line 148, in __init__
Dec 16 10:57:27 h2989788 celery[128418]: BaseRotatingHandler.__init__(self, filename, mode, encoding, delay)
Dec 16 10:57:27 h2989788 celery[128418]: File "/usr/lib/python3.8/logging/handlers.py", line 55, in __init__
Dec 16 10:57:27 h2989788 celery[128418]: logging.FileHandler.__init__(self, filename, mode, encoding, delay)
Dec 16 10:57:27 h2989788 celery[128418]: File "/usr/lib/python3.8/logging/__init__.py", line 1147, in __init__
Dec 16 10:57:27 h2989788 celery[128418]: StreamHandler.__init__(self, self._open())
Dec 16 10:57:27 h2989788 celery[128418]: File "/usr/lib/python3.8/logging/__init__.py", line 1176, in _open
Dec 16 10:57:27 h2989788 celery[128418]: return open(self.baseFilename, self.mode, encoding=self.encoding)
Dec 16 10:57:27 h2989788 celery[128418]: PermissionError: [Errno 13] Permission denied: '/home/django/FLY/logs/myrate.log'
Dec 16 10:57:27 h2989788 celery[128418]: The above exception was the direct cause of the following exception:
Dec 16 10:57:27 h2989788 celery[128418]: Traceback (most recent call last):
Dec 16 10:57:27 h2989788 celery[128418]: File "/home/django/env/lib/python3.8/site-packages/kombu/utils/imports.py", line 56, in symbol_by_name
Dec 16 10:57:27 h2989788 celery[128418]: module = imp(module_name, package=package, **kwargs)
Dec 16 10:57:27 h2989788 celery[128418]: File "/home/django/env/lib/python3.8/site-packages/celery/utils/imports.py", line 105, in import_from_cwd
Dec 16 10:57:27 h2989788 celery[128418]: return imp(module, package=package)
Dec 16 10:57:27 h2989788 celery[128418]: File "/usr/lib/python3.8/importlib/__init__.py", line 127, in import_module
Dec 16 10:57:27 h2989788 celery[128418]: return _bootstrap._gcd_import(name[level:], package, level)
Dec 16 10:57:27 h2989788 celery[128418]: File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
Dec 16 10:57:27 h2989788 celery[128418]: File "<frozen importlib._bootstrap>", line 991, in _find_and_load
Dec 16 10:57:27 h2989788 celery[128418]: File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
Dec 16 10:57:27 h2989788 celery[128418]: File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
Dec 16 10:57:27 h2989788 celery[128418]: File "<frozen importlib._bootstrap_external>", line 848, in exec_module
Dec 16 10:57:27 h2989788 celery[128418]: File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
Dec 16 10:57:27 h2989788 systemd[1]: celery.service: Control process exited, code=exited, status=2/INVALIDARGUMENT
Dec 16 10:57:27 h2989788 celery[128418]: File "/home/django/FLY/theApp/__init__.py", line 1, in <module>
Dec 16 10:57:27 h2989788 celery[128418]: from .celery import app as celery_app
Dec 16 10:57:27 h2989788 celery[128418]: File "/home/django/FLY/theApp/celery.py", line 18, in <module>
Dec 16 10:57:27 h2989788 celery[128418]: configurations.setup()
Dec 16 10:57:27 h2989788 celery[128418]: File "/home/django/env/lib/python3.8/site-packages/configurations/__init__.py", line 31, in setup
Workaround: change the permissions of the log file, which belongs to user django, so that user celery can write to it. But as we're using a rotating logger, this only helps until the next log-file is created.
Solutions we thought of:
Changing the access-rights of the file every time a new log-file is created: probably the worst way of handling this
Using the same user for the django- and celery-processes: smells like the last resort
Creating a specific run-configuration in settings.py overwriting the logging handlers like so:
class CeleryProd(Prod):
def __init__(self) -> None:
super().__init__()
self.LOGGING['handlers']={}
But somehow every of these solutions seems like a workaround to me - even the last one seems a bit clumsy. Mustn't there be a way of doing it right?
How have you done it?