[Issue]: Wrong MIME type returned for different comic book formats

[rluetzner]

Please describe your bug

As described in jellyfin/jellyfin-plugin-opds#38 , I noticed that the current MIME type implementation does not account for different comic book formats. It will always return application/x-cbr.

Sadly cbr (a.k.a. Rar) is a proprietary compression algorithm, so most FOSS eReaders won't be able to download or display such files.

I couldn't pinpoint the exact place where this goes wrong, but I noticed that this case is not covered by the tests in MimeTypeTests.cs. However, I also couldn't find a place where x-cbr is explicitly set, so I'm still not sure where this bug is coming from.

Reproduction Steps

Is reproducible by adding cbr and cbz to the MimeTypesTests class like this:

        [InlineData(".cbr", "application/x-cbr")]
        [InlineData(".cbz", "application/x-cbz")]

[xUnit.net 00:00:00.73]     Jellyfin.Model.Tests.Net.MimeTypesTests.GetMimeType_Valid_ReturnsCorrectResult(input: ".cbz", expectedResult: "application/x-cbz") [FAIL]
  Fehler Jellyfin.Model.Tests.Net.MimeTypesTests.GetMimeType_Valid_ReturnsCorrectResult(input: ".cbz", expectedResult: "application/x-cbz") [1 ms]
  Fehlermeldung:
   Assert.Equal() Failure: Strings differ
                           ↓ (pos 16)
Expected: "application/x-cbz"
Actual:   "application/x-cbr"
                           ↑ (pos 16)

Jellyfin Version

10.8.13

if other:

No response

Environment

- OS:
- Linux Kernel:
- Virtualization:
- Clients:
- Browser:
- FFmpeg Version:
- Playback Method:
- Hardware Acceleration:
- GPU Model:
- Plugins:
- Reverse Proxy:
- Base URL:
- Networking:
- Storage:

Jellyfin logs

-

FFmpeg logs

No response

Please attach any browser or client logs here

No response

Please attach any screenshots here

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[nielsvanvelzen]

You can look at #10980 to see how to update the mime type mappings.

[rluetzner]

Thanks @nielsvanvelzen . I'll get to work, depending on the answer I get to khellang/MimeTypes#23 . 🙂

It's actually a bug in the MimeTypes package Jellyfin uses, so I'd rather have it fixed there and have other projects benefit from this as well.

Thanks for the quick response.

[felix920506]

I think you would get a quicker fix by fixing it on the JF side, given that the last commit on upstream is from 9 months ago

[rluetzner]

Thanks for the advice @felix920506 . I did both. 🙂