Hello, I am experiencing a persistent issue with deploying a FastAPI application with a WebSocket endpoint on Hugging Face Spaces. All WebSocket connection attempts fail with server rejected WebSocket connection: HTTP 404, while standard HTTP GET requests to the same application work perfectly. Th…

Perhaps this case? [image] Chainlit WebSocket Issue on Hugging Face Spaces: Missing websockets in Requirements? Spaces I started using Hugging Face Spaces just a few hours ago and noticed that my simple Chainlit app wasn’t working correctly. The app itself is straightforwa…

server rejected WebSocket connection: HTTP 404 :slightly_frowning_face:

I wonder if this bug (?) is also occurring in FastAPI…:thinking: [image] Persistent 404 on Docker Space - app_port routing seems to be ignored (User: josejar) Spaces Hello Hugging Face community and team, I am writing to report a persistent and blocking issue with every D…

FYI, I also had error with websocket and my mistake was to use ws:// instead of wss://

FastAPI WebSocket returns HTTP 404 on Spaces

Spaces

John6666 June 19, 2025, 7:18am 2

Perhaps this case?

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FastAPI WebSocket returns HTTP 404 on Spaces

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