Flask Integration Notifier does not work outside request context

[sarartur]

What

👋 I am currently experiencing the following issue:

The notifier app.extensions['pybrake'] does not work outside request context due to this check:

pybrake/src/pybrake/middleware/flask.py

Lines 34 to 35 in f506588

	if request is None:
	return notice

Outside of request context flask returns <LocalProxy unbound> which is a truthy value, so it tries to run the filter and raises RuntimeError: Working outside of request context.

Flask version: 3.1.1
Pybrake version: 1.10.1

Why

This is an issue if trying to then pass integration the same notifier with celery via patch_celery(flask_app.extensions["pybrake"]) for example or if you want to use notifier outside of request context like in CLI command / task for example.

Current workaround

I am able to get this working by filtering out the filter before passing it to celery:

airbrake_notifier._filters = [
    f for f in airbrake_notifier._filters if f.__name__ != 'request_filter'
]

But obviously accessing 'private' var _filters is not ideal

Proposal

Would it be possible to add further handling to skip this filter if working outside of request context? Happy to submit a PR to the upstream. Thanks :)