websocket.close throws runtime error on a closed websocket.

[tobiashagge]

I have the following situation:

1. I call 'await websocket.close(...)
2. The awaitable gets its turn on the async queue and calls 'await websocket.send(...)' to send a 'websocket-close' message.
3. Some time after step (1) but before step (4), the websocket gets closed.
4. The second awaitable gets its turn on the async queue and tries to send the message.
5. websocket.send throws a RuntimeError because the socket is closed.

This doesn't seem like correct behavior. Shouldn't it be either:

1. websocket.close catches the exception silently and returns without complaint, because there is nothing more to do, -or-
2. websocket.send throws a starlette-specific exception, either WebsocketDisconnect or something new.

[Kludex]

Bump starlette and uvicorn to the latest release. This behavior should be old.