APScheduler KeyError: 'cron' during startup

[MeisterLLD]

Describe the bug/problem
Launching cps in a terminal gives me the following message. Last time I've tried before that, it worked well.

Traceback (most recent call last):
File "/home/lld/.local/lib/python3.10/site-packages/apscheduler/schedulers/base.py", line 900, in _create_plugin_inst
plugin_cls = class_container[alias]
KeyError: 'cron'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/lib/python3.10/site-packages/pkg_resources/init.py", line 3037, in _dep_map
return self.__dep_map
File "/usr/lib/python3.10/site-packages/pkg_resources/init.py", line 2834, in getattr
raise AttributeError(attr)
AttributeError: _DistInfoDistribution__dep_map

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/home/lld/.local/bin/cps", line 8, in
sys.exit(main())
File "/home/lld/.local/lib/python3.10/site-packages/calibreweb/cps/main.py", line 26, in main
app = create_app()
File "/home/lld/.local/lib/python3.10/site-packages/calibreweb/cps/init.py", line 173, in create_app
register_scheduled_tasks(config.schedule_reconnect)
File "/home/lld/.local/lib/python3.10/site-packages/calibreweb/cps/schedule.py", line 67, in register_scheduled_tasks
scheduler.schedule(func=end_scheduled_tasks, trigger='cron', name="end scheduled task", hour=end_time.hour,
File "/home/lld/.local/lib/python3.10/site-packages/calibreweb/cps/services/background_scheduler.py", line 52, in sch
return self.scheduler.add_job(func=func, trigger=trigger, name=name, **trigger_args)
File "/home/lld/.local/lib/python3.10/site-packages/apscheduler/schedulers/base.py", line 424, in add_job
'trigger': self._create_trigger(trigger, trigger_args),
File "/home/lld/.local/lib/python3.10/site-packages/apscheduler/schedulers/base.py", line 925, in _create_trigger
return self._create_plugin_instance('trigger', trigger, trigger_args)
File "/home/lld/.local/lib/python3.10/site-packages/apscheduler/schedulers/base.py", line 903, in _create_plugin_inst
plugin_cls = class_container[alias] = plugin_container[alias].load()
File "/usr/lib/python3.10/site-packages/pkg_resources/init.py", line 2470, in load
self.require(*args, **kwargs)
File "/usr/lib/python3.10/site-packages/pkg_resources/init.py", line 2492, in require
reqs = self.dist.requires(self.extras)
File "/usr/lib/python3.10/site-packages/pkg_resources/init.py", line 2755, in requires
dm = self._dep_map
File "/usr/lib/python3.10/site-packages/pkg_resources/init.py", line 3039, in _dep_map
self.__dep_map = self._compute_dependencies()
File "/usr/lib/python3.10/site-packages/pkg_resources/init.py", line 3056, in _compute_dependencies
common = types.MappingProxyType(dict.fromkeys(reqs_for_extra(None)))
File "/usr/lib/python3.10/site-packages/pkg_resources/init.py", line 3053, in reqs_for_extra
if not req.marker or req.marker.evaluate({'extra': extra}):
File "/home/lld/.local/lib/python3.10/site-packages/packaging/markers.py", line 241, in evaluate
return _evaluate_markers(self._markers, current_environment)
File "/home/lld/.local/lib/python3.10/site-packages/packaging/markers.py", line 150, in _evaluate_markers
lhs_value, rhs_value = _normalize(lhs_value, rhs_value, key=environment_key)
File "/home/lld/.local/lib/python3.10/site-packages/packaging/markers.py", line 124, in _normalize
return tuple(canonicalize_name(v) for v in values)
File "/home/lld/.local/lib/python3.10/site-packages/packaging/markers.py", line 124, in
return tuple(canonicalize_name(v) for v in values)
File "/home/lld/.local/lib/python3.10/site-packages/packaging/utils.py", line 34, in canonicalize_name
value = _canonicalize_regex.sub("-", name).lower()
TypeError: expected string or bytes-like object

Before that cps complained that I didn't have the python module 'certifi', so I installed it. It didn't need it until more or less recently. Sorry that I can't be more precise, I haven't been using calibre-web in a few weeks.

To Reproduce
Steps to reproduce the behavior: launch cps.

Logfile
My logfile has no useful info, the last entry is from 2022-11-14 when it worked.

Expected behavior
No Python exceptions.

Screenshots

Environment (please complete the following information):

• OS: Arch Linux 6.1.4
• Python version: 3.10.9
• Calibre-Web version: Calibre-Web version: 0.6.19 - unknown git-clone

[OzzieIsaacs]

Error is caused by not properly installed AP Scheduler dependency (reference: agronholm/apscheduler#77)

[rsulliv1]

cause of Technosoft2000/docker-calibre-web#125