WebSocketSubject fails to recreate socket when close isn't immediate

Bug Report

Current Behavior If the close of a websocket takes a little bit of time subsequent calls to multiplex fail to send any subscription messages and close the socket immediately. See reproduction below.

Reproduction

• https://stackblitz.com/edit/rxjs-n2kgl6

import { interval } from "rxjs";
import { webSocket } from "rxjs/webSocket";
import { switchMap, take } from "rxjs/operators";

const socket = webSocket<any>({
  url: "ws://localhost/ws"
});

interval(2_000)
  .pipe(
    take(2),
    switchMap(id => {
        return socket.multiplex(
          () => `sub ${id}`,
          () => `unsub ${id}`,
          value => value === id
        );
    })
  )
  .subscribe({
    next: _ => { },
    error: err => console.error(err),
    complete: () => console.log("Complete")
  });

Expected behavior A new call to multiplex should subscribe and stay open.

Environment

• 6.4.0

[markmcdowell]

My use case here is I have 2 tabs in a UI, when I change tabs I unsubscribe to a stream, which starts to close the connection. The new tab makes a different subscribe but this fails as as the close isn’t complete.

My current work around is to delay new subscriptions by 250ms, but this is really dependant on how long the connection takes to close.

[ahnpnl]

Another approach to fixing this might be to set a property on the class (like _socketOpening) when a socket is opened via _connectSocket to true and check for that in socket.onclose and not call resetState if that value is true. Then once socket.onopen is called, you would set that value to false.

I ran into the same issue and I also used this fix to solve my problem.