shutdown()

in src/bridge.js [84:119]

• 20 lines of code
• 4 McCabe index (conditional complexity)

  shutdown() {
    if (this._isShutdown) {
      console.warn('Bridge was already shutdown.');
      return;
    }

    // Queue the shutdown outgoing message for subscribers.
    this.send('shutdown');

    // Mark this bridge as destroyed, i.e. disable its public API.
    this._isShutdown = true;

    // Disable the API inherited from EventEmitter that can add more listeners and send more messages.
    (this: any).addListener = function() {};
    this.emit = function() {};
    // NOTE: There's also EventEmitter API like `on` and `prependListener` that we didn't add to our Flow type of EventEmitter.

    // Unsubscribe this bridge incoming message listeners to be sure, and so they don't have to do that.
    this.removeAllListeners();

    // Stop accepting and emitting incoming messages from the wall.
    const wallUnlisten = this._wallUnlisten;
    if (wallUnlisten) {
      wallUnlisten();
    }

    // Synchronously flush all queued outgoing messages.
    // At this step the subscribers' code may run in this call stack.
    do {
      this._flush();
    } while (this._messageQueue.length);

    // Make sure once again that there is no dangling timer.
    clearTimeout(this._timeoutID);
    this._timeoutID = null;
  }