Issue Starting with AMQP Backend with Python 3.7

I’m running the code through celery and an not sure how to get the right error message out of this stack dump. Seems like an error occurred and then when celery/kombu tried to handle it that process also barfed.

ingestbackend_1     | [2018-07-11 04:25:25,661: CRITICAL/MainProcess] Unrecoverable error: SyntaxError('invalid syntax', ('/usr/local/lib/python3.7/site-packages/celery/backends/rpc.py', 20, 11, 'from .async import AsyncBackendMixin, BaseResultConsumer\n'))
ingestbackend_1     | Traceback (most recent call last):
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/kombu/utils/objects.py", line 42, in __get__
ingestbackend_1     |     return obj.__dict__[self.__name__]
ingestbackend_1     | KeyError: 'backend'
ingestbackend_1     |
ingestbackend_1     | During handling of the above exception, another exception occurred:
ingestbackend_1     |
ingestbackend_1     | Traceback (most recent call last):
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/worker/worker.py", line 205, in start
ingestbackend_1     |     self.blueprint.start(self)
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/bootsteps.py", line 115, in start
ingestbackend_1     |     self.on_start()
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/apps/worker.py", line 139, in on_start
ingestbackend_1     |     self.emit_banner()
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/apps/worker.py", line 154, in emit_banner
ingestbackend_1     |     ' \n', self.startup_info(artlines=not use_image))),
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/apps/worker.py", line 217, in startup_info
ingestbackend_1     |     results=self.app.backend.as_uri(),
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/kombu/utils/objects.py", line 44, in __get__
ingestbackend_1     |     value = obj.__dict__[self.__name__] = self.__get(obj)
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/app/base.py", line 1196, in backend
ingestbackend_1     |     return self._get_backend()
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/app/base.py", line 914, in _get_backend
ingestbackend_1     |     self.loader)
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/app/backends.py", line 70, in by_url
ingestbackend_1     |     return by_name(backend, loader), url
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/app/backends.py", line 50, in by_name
ingestbackend_1     |     cls = symbol_by_name(backend, aliases)
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/kombu/utils/imports.py", line 56, in symbol_by_name
ingestbackend_1     |     module = imp(module_name, package=package, **kwargs)
ingestbackend_1     |   File "/usr/local/lib/python3.7/importlib/__init__.py", line 127, in import_module
ingestbackend_1     |     return _bootstrap._gcd_import(name[level:], package, level)
ingestbackend_1     |   File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
ingestbackend_1     |   File "<frozen importlib._bootstrap>", line 983, in _find_and_load
ingestbackend_1     |   File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
ingestbackend_1     |   File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
ingestbackend_1     |   File "<frozen importlib._bootstrap_external>", line 724, in exec_module
ingestbackend_1     |   File "<frozen importlib._bootstrap_external>", line 860, in get_code
ingestbackend_1     |   File "<frozen importlib._bootstrap_external>", line 791, in source_to_code
ingestbackend_1     |   File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
ingestbackend_1     |   File "/usr/local/lib/python3.7/site-packages/celery/backends/rpc.py", line 20
ingestbackend_1     |     from .async import AsyncBackendMixin, BaseResultConsumer
ingestbackend_1     |               ^
ingestbackend_1     | SyntaxError: invalid syntax

Any thoughts on how to debug this would be good.

[auvipy]

well seems it’s celery issue and its fixed in celery master recently. celery isn;t officially supporting 3.7 yet, so either down grade to 3.6 or try celery master and report further issues

[yuriizinets]

Also, here is possible solution, but with modification of library code. https://stackoverflow.com/questions/51273659/trouble-in-setting-celery-tasks-backend-in-python/51308631