Multiple compressions when mounting with FastAPI

[rhysrevans3]

When using FastAPI's mounting on an app with BrotliMiddleware the body is compressed twice.

[keul]

Any news on this?

[fullonic]

@rhysrevans3 I apologize for the delay, and I appreciate your effort in raising the issue and opening a PR.
I have tried running your code locally, and the tests are not passing.
I would like to review your scenario and fix the errors. If you are still using the library, could you provide a code example to reproduce the issues?

Do you mean mounting an app that uses BrotliMiddleware into the main FastAPI app that also uses this middleware?

[keul]

I also noticed this issue once, I'm trying to recover the usecase

[keul]

FYI: not able to reproduce, but I cannot find/remember when I saw this is action, wondering is this could be related to other changes (like starlette or fastapi)

[rhysrevans3]

Hi both sorry for the delayed response. If remember correctly I was seeing this issue when using FastAPI's sub app mounting this was causing the compression to be run twice. There might be a better solution than my PR to prevent the middleware running twice but I couldn't see a reason to run the compression twice anyway so a header check seemed the quickest and simplest solution.