Trouble understanding sockets.io room

I am trying to configure a 1v1 game with multiple rooms on my server with sockets.io. When the user create a room, a random alphanumeric identifier of 5 letters is generated and the user joins the room.

 function handleNewGame() {
        let roomName = makeid(5);
        client.join(roomName);
  }

Then another user is supposed to join with the room name. The room name is taken from a tag inside the html main page and then is sent by a function.
This is the function that handles game joining on server side

function handleJoinGame(roomName) {
        const room = io.sockets.adapter.rooms[roomName];
}

All of this is wrapped inside an

io.on('connection', client => {
}

The problem is that at this point, before the other user even tries to join, the room is undefined.

console.log(room);

This gives me undefined.
If I try to actually print out all the rooms, it actually exist, but the method can’t find it. What did I do wrong?

>Solution :

Forget the library for a moment. Conceptually, a room is just a group of users. an array of socket connections to whom you broadcast using a for loop. It should come with a room manager since you want to have many rooms otherwise you had single room anyway.

Let’s assume an object of arrays.

var roomManager = {
  "room12345" : [socket1, socket2, socket5],
  "room76432" : [socket3, socket4],
}

and when socket1 wants to broadcast, you know its room room12345 so you broadcast to all others in that room.

So really you can implement this logic yourself quite easily.