WebSocket disconnect event

[Kludex]

Hi there 👋

I need help. 👀

Let's assume that our client sent some data, the server was able to receive that data, and it's about to send that to the application. In the meantime, the application sent a close message.

What do I do with the data that just arrived?

Motivation comes from encode/uvicorn#1619.

[andrewgodwin]

I mean this is a classic race condition - it depends. I'd say that it's probably more expected to not send it to the application and just drop it - while you could argue what the spec says or doesn't here, there's never a guarantee you'll receive data anyway and dropping it is much less surprising than trying to serve the application data after it's asked to close.

[Kludex]

I had the same thoughts. I'll comply with that reasoning on uvicorn - which is basically continuing with the current behavior.

As always, much appreciated. Thanks @andrewgodwin 🙏