Make django.contrib.auth decorators work with async functions.

[Mike Lissner]

We're slowly moving our code base over to async views and tests. Django 5.0 is a big leap forward for this, but we've found that there's still no async version of the @login_required decorator.

We're working around it with some funky decorator usage:

@sync_to_async
@login_required
@async_to_sync
async def our_view(request):

Buuuut, it'd be great not to need to do all this and to either have an async version of login_required (@alogin_required, perhaps?) or for it to just work with async views.

I don't think there's an open issue for this, but amusingly, in a comment 11 months ago, Carlton Gibson touched on making login_required work with async, but he thought it'd take another five years. Perhaps we can do better. :)

[Mariusz Felisiak]

Related to #34391 and #31949.

[Dingning]

Thank you for CC'ing me. I will study how this function can be implemented, and consider whether I can take on this ticket. I will reply within a day.

[Dingning]

OK, I have achieved a simple demo, I think I can work on this ticket. I'll improve my code further, then submit a PR as soon as possible.

[Dingning]

Here is my PR.
​https://github.com/django/django/pull/17621

[Natalia Bidart]

Hello Dingning, thanks for your work on this ticket. Once your PR is ready for review, please unset the flags "Patch needs improvement" and "Needs documentation" so it appears in the review queue (​docs about this).

[Dingning]

Hi guys, I created a topic to discuss, welcome to chat here(​https://forum.djangoproject.com/t/about-async-version-of-the-login-required-decorator/27077)

[Dingning]

Hello, dear reviewers. I have updated my commit. Could you please review the pull request?

[GitHub <noreply@…>]

In c4df2a77:

Refs #35030 -- Added more tests for @user_passes_test decorator.

[Mariusz Felisiak <felisiak.mariusz@…>]

In 5493209:

Fixed #35030 -- Made django.contrib.auth decorators to work with async functions.