Support panel fastapi behind reverse proxy

[MarcSkovMadsen]

Partial fix for #7277

An attempt to fix or make it easier to fix #7277.

[MarcSkovMadsen]

After fixing the initial issue the next issue is that it tries to find the static assets at /static/.... But with a start command like fastapi dev script.py --root-path /some/path that is not where they should be served.

This would also be a problem for anyone trying to deploy this in a docker container and not at /.

I will need help to solve this.

Update: If I run the command fastapi dev script.py it looks like the app is also available at the same url and its trying to find static assets at /static where it should be looking at /some/path/static.

[philippjfr]

Doubtful this can/should be fixed in Panel. The improved handling probably has to be in bokeh-fastapi.

[philippjfr]

The location fix looks fine to me.

[philippjfr]

pre-commit.ci autofix

[codecov]

Codecov Report

Attention: Patch coverage is 89.74359% with 4 lines in your changes missing coverage. Please review.

Project coverage is 82.17%. Comparing base (19025e1) to head (369d7a0).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
panel/io/location.py	88.23%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7278      +/-   ##
==========================================
- Coverage   82.19%   82.17%   -0.03%     
==========================================
  Files         337      337              
  Lines       50363    50376      +13     
==========================================
- Hits        41398    41397       -1     
- Misses       8965     8979      +14     

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[MarcSkovMadsen]

Doubtful this can/should be fixed in Panel. The improved handling probably has to be in bokeh-fastapi.

Do I need to do anything here?