Stream endpoint doesn't work with GZipMiddleware

[kikohs]

I was struggling to understand why a RemoteRunnable.stream was not working from langchain JS in the browser

Disabling GZipMiddleware in FastAPI made it work again.
Not sure if it's a Starlette/Uvicorn issue or LangServe but might be useful to fix/report.

[eyurtsev]

tiangolo/fastapi#8448

[eyurtsev]

Does that sound like the same issue?

[kikohs]

Not sure about the langserve underlying implementation. Here the streaming response is initiated in the browser correctly (with text/event-stream) from langchainJS, when the OpenAI API finishes, all the streaming events are returned.

Like if we were awaiting for the whole response and delivering at once (return instead of yield)