WebSocketSubject should error instead of complete if the close code is an error code

[andresemartinez]

It would be nice to have a way of specifying if a close code is an error or not. Currently the callback configured in the onclose of the websocket only checks the wasClean flag, but it is false only if there was no close handshake. I need to be able to close the socket from the server specifying an error code (like 3000 - Unauthroized) and have an error in the subject instead of a complete.

This is the current implementation:

    socket.onclose = (e: CloseEvent) => {
      if (socket === this._socket) {
        this._resetState();
      }
      const { closeObserver } = this._config;
      if (closeObserver) {
        closeObserver.next(e);
      }
      if (e.wasClean) {
        observer.complete();
      } else {
        observer.error(e);
      }
    };

I think w3c does not specify an error code segment so I was thinking on being able to configre a function in the WebSocketSubjectConfig to determine if the code is an error in my particular implementation.