Getting the "Close" message.

[emanuele3d]

First of all apologies for opening a bug report (issue #6707) for something that wasn't a bug.

Thank you @Dreamsorcerer for pointing me to the relevant code though.

Assuming this code as context:

async for message in ws:
    self.handle(message)

during normal operations the ClientWebSocketResponse.__anext__ method returns the message received by the client and self.handle() processes it. But I'm guessing if the server sends a message of type WSMsgType.CLOSE, WSMsgType.CLOSING, WSMsgType.CLOSED, the async for loop ends due to the raise StopAsyncIteration and for that last message the self.handle() method is not called.

The closure message can be quite important though. I.e. the server I'm dealing with might issue a closing message asking me to -not- attempt reconnection for, say, 10 minutes instead of attempting reconnection after a few seconds. Attempting to reconnect too soon might result in administrative actions such as a temporary or permanent ban.

So, is there a way to access that last message in full? I notice the ClientWebSocketResponse class has a close_code property, which helps, but is not the full message.

If there is no way, could this simple change to the ClientWebSocketResponse.__anext__ code be acceptable:

async def __anext__(self) -> WSMessage:
    msg = await self.receive()
    if msg.type in (WSMsgType.CLOSE, WSMsgType.CLOSING, WSMsgType.CLOSED):
        self.close_msg = msg        (added line to keep the closure message)
        raise StopAsyncIteration
    return msg

[emanuele3d]

Having looked at the code a little better, the suggestion above would also help to discriminate between the case where the loop ends because of the three closure messages and the case where a WebSocketError exception is thrown by the receive method: in that case the self.close_msg would remain set to None, its default value, while close_code would be set to webSocketError.code.