Attaching a Shared Object To Socket.io Room

Question

I'm creating a multiplayer game that can have many game rooms and I want to associate a game object (or game state) per room; I am using NodeJS, Socket.io, socket.io-redis (not sure if this one is even needed).

Just to be more clear, I am using Typescript as well.

I have tried using socket.io-redis' remoteJoin() function and successfully setting a game object to the room by using

io.of('/').adapter.rooms[<roomId>].game = Game.

However, I read that this is not the proper way of setting a room wide object.

Event for creating a room

socket.on('create-game', (createData: any) => {
    this.io.of('/').adapter.remoteJoin(socket.id, createData.roomId, (err: any) => {
        let player = new Player(createData.username)
        let game = new Game(createData.roomId)

        game.addPlayer(player)

        this.io.of('/').adapter.rooms[createData.roomId].game = game
    })
})

Event for joining a room

socket.on('join-game', (joinData: any) => {
    this.io.of('/').adapter.remoteJoin(socket.id, joinData.roomId, (err: any) => {
        let player = new Player(joinData.username)
        let game = this.io.of('/').adapter.rooms[joinData.roomId].game as Game

        game.addPlayer(player)
    })
})

What happens on the create-game event:

1. the data coming in is used to create a Player
2. and a Game object
3. then the player is added to the game object
4. finally, the game object is added to the room

What happens on the join-game event:

1. the data coming in is used to create a Player
2. the Game object is created by retrieving it from the room
3. player is added to the game object

After countless days/weeks? of searching, I stumbled on this Stackoverflow thread: socket.io, how to attach state to a socket room

What this answer is saying is to basically not do what I did above. Their suggestion is to create your own data structure (not sure how to even begin doing this).

Other answers I've found say to just create a global variable in the server, but again, others say this is bad practise (which I think as well).

Another popular answer is to store the game in Redis, but Redis cannot hold complex Javascript objects. I now that Redis can hold hash data, via the hmset() function, but I found this to not work with something as complex as a Game object, with functions, constructors, and getters/setters.

One more answer that stands out is to only store the game to the DB after a "round", but in my case, once the game is finished, the room is closed and the associated game is destroyed; I don't need to persist this game in the sense of "saving a game".