fix: fix 404 page bug when accessing wrong static files.

[Lucas-lyh]

This #2570 issue is because starlette modify request.route['root_path'] when routing static files mount. I just reset this field when handling 404 page request.
I'm a beginner in nicegui and may miss something. On my machine, all test passed and the bug is fixed.
I also add a test for 404 page.

[rodja]

Interesting. Will it still work with subpath mounting? Like in our example https://github.com/zauberzeug/nicegui/tree/main/examples/nginx_subpath?

[Lucas-lyh]

Interesting. Will it still work with subpath mounting? Like in our example https://github.com/zauberzeug/nicegui/tree/main/examples/nginx_subpath?

Yes!
I have to confess that I forgot to exam this situation. In my test, subpath mounting works well because prefix is assigned to X-Forwarded-Prefix in headers if exist, instead of route['root_path']. In fact because of that, 404 page bug is masked when working with subpath mounting.

[Lucas-lyh]

Updated 404_test to prevent other test from being affected.

[rodja]

Cool. And what about sub-mounting in another app as we do in the fastAPI example: https://github.com/zauberzeug/nicegui/tree/main/examples/fastapi

[Lucas-lyh]

Cool. And what about sub-mounting in another app as we do in the fastAPI example: https://github.com/zauberzeug/nicegui/tree/main/examples/fastapi

Thank you for your reminder, my fix gose wrong when working with app.run_with().
How about add a AppConfig field to save the correct root path, then use this path to generate 404page? I've tried to solve it but I'm not sure if it is reasonable.

[falkoschindler]

Thank you so much for your contribution, @Lucas-lyh!
Your pull request sparked the idea of @rodja's PR #2746, which seems to have solved issue #2570. 🚀