There doesn't appear to be a way to track room creation/deletion

You want to:

• report a bug
• request a feature

Current behaviour

Right now, it appears that rooms are a socket-level construct only. Individual connections appear to know what rooms they’re a part of. Adapters like socket.io-redis appear to have just enough functionality to know how to route messages to all members of a room.

Expected behaviour

In many applications, socket.io will sit on top of a room that represents some potentially costly resource. For instance, in my use case, I want to spin up a docker container to be used by everyone in a room. That means I need to know when to create one and when to delete one when it’s no longer being used.

I can try to track room membership on my own, but then I become a central point of failure anyhow.

Suggestion

In a system like the one socket.io-redis suggests, I think it should be possible for all nodes to subscribe to when rooms are created or destroyed, since those changes should be pubbed through redis already.

[darrachequesne]

Well, I guess we could emit an event when a room is created:

https://github.com/socketio/socket.io-adapter/blob/1.1.0/index.js#L56

for (var i = 0; i < rooms.length; i++) {
    var room = rooms[i];
    this.sids[id] = this.sids[id] || {};
    this.sids[id][room] = true;
    if (!this.rooms.hasOwnProperty(room)) {
      this.rooms[room] = Room();
      this.emit('create-room', room);
    }
    this.rooms[room].add(id);
}
// and then
io.of('/').adapter.on('create-room', /* */);

What do you think?

[darrachequesne]

@Tsourdox no, this is not currently possible, but we could add this I guess 👍