Can you explain why socket.io disconnect doesn't work?

Ionic Framework ionic-v3
1

Hi everyone!

I’m using socket.io with Ionic 3.x

My app has two kinds of status. Let’s call the first one “checked in” and the second one “checked out.”

Upon check in I call

this.socket.connect();
this.socket.emit(SERVER_SOCKET_JOIN_ROOM, SERVERSOCKET_TYPE);

This succesfully joins the user and I get all the realtimedata that I need! :slight_smile: Meaning checked in users get certain data over the socket.

Here comes the bad part (you can hopefully advice me on what I did wrong):

When the user checks out or gets checked out, I call

this.socket.disconnect()

According to the socket.io docs the disconnect function automatically leaves all rooms.
I even checked on the server side, if the disconnect was successful:

socket.on('disconnect', function(){
  console.log('Disconnection happened.');
});

It is succesful.
But, when I rejoin the server, all the data passed to the checked in users using the socket now appears twice!

If I repeat the process (check out, followed by a checkin) the user get the data three times!

I checked on the server side: The data only gets put out once (I console logged everytime something gets logged out by the server).

I don’t know what to do, any advice would be much appreciated!

2

I also experienced this strange behaviour in one of my apps. My current solution is to remove all event listeners which I’ve previously created just before calling disconnect() like this:

this.socket.removeAllListeners('youraction');

The problem otherwise is that these event listeners keep existing although you are logged out from socket!

1 Like
3

Thank you for your answer saimon! I learned how to use sockets from your video :slight_smile:

So in my example I would have to call:

this.socket.removeAllListeners(SERVER_SOCKET_JOIN_ROOM);

As SERVER_SOCKET_JOIN_ROOM is the event I emit to join the room?

The code on the node app is:

socket.on('join-room', (room) => {
    console.log("Room " + room + " joined");
    socket.join(room);
  });
4

Yeah I think that should fix the problem! Glad you started out with my video :slight_smile:

1 Like