Sending a specific socket.id data with node.js/socket.io

[IamThatGuy]

So I have my server running and I can't figure out how to send to the specific socket.ID. The code in dispatchGameMessage may look funny bcuz I been trying various things to send to the 2 people in the Game. Google isn't helping much with this. And now some code snipplets:

// varsvar express = require('express');var app = express();var server = require('http').createServer(app);var io = require('socket.io')(server);var port = 3000;  server.listen(port, function () {  console.log('Server listening at port %d', port);}); // Routingapp.use(express.static(__dirname));  // usernames which are currently connected to the chatvar i = 0;var channels = {};var channelRefs = {};var numUsers = 0;var clientHoles = new Array();var found = false; io.on('connection', function (socket) {    // when the client emits "C" - Create Channel/Join, this listens and executes  socket.on('C', function (data) {  console.log("Data Connect" + socket.id, port); found = false;//increase # of clients connected++numUsers; // we store the numUsers as socket session usernamesocket.username = data; addedUser = true; //first user connectedif(numUsers == 1){channels[data] = socket.id;socket.emit('W', "W");}else{//go through every connection availablefor(i = 1; i < numUsers; i++){console.log(channels[data], port);//if channel has a player in itif(channels.hasOwnProperty(data) && channels[data] != -1){socket.emit('W', socket.id);channelRefs[data] = {id1: channels[data], id2: socket.id};channels[data] = -1; //game in progress/finished//this may also be the problemdispatchGameMessage(data, "S", socket);found = true;break;}} //if channel not found, create itif(found == false){socket.emit('W', socket.id);channels[data] = socket.id;}}});    });});  //the problem is in here =]// Sends game command to channel (Game In Progress)function dispatchGameMessage (chan_name, data, sock) {//channelRefs[chan_name].id1 and channelRefs[chan_name].id2 are different if(data == "C"){console.log("ID 1 = " + channelRefs[chan_name].id1);console.log("ID 2 = " + channelRefs[chan_name].id2);}//bleeeeeeeeeeeeif(data.length == 1){//sock.broadcast(data, data);sock.socket(channelRefs[chan_name].id2).emit(data, channelRefs[chan_name].id2); sock.socket(socket(channelRefs[chan_name].id1)).emit(data, channelRefs[chan_name].id1); }}

 

No matter what I do, it sends the message be the client(socketID) that sent the message.

[bulkan]

Your channels implementation seems like rooms in socket.io why not just use rooms ?

 

http://socket.io/docs/rooms-and-namespaces/#rooms

[Bruno Assarisse]

I agree, rooms would be a more adequate solution.

 

Anyway, to send data to a specific socket:

io.to(socket.id).emit("event", data);

The io.to() method is used to emit message to a room, and every socket is placed in a room named after its ID (which is documented on the link @bulkan provided).

[IamThatGuy]

thanks guys. i didnt know about rooms.

[IamThatGuy]

Is there a built in function/method to get the # of people in a certain room?

[Gio]

Yes, but it depends on your version of socket.io

With newer versions you can do

Object.keys(io.nsps[namespace].adapter.rooms[room]).length

Where namespace is the namespace you are using, or '/' which is the default namespace, and room is the name of your room.

With older versions (when namespaces didn't exist) you'd do:

io.sockets.clients(room).length

[IamThatGuy]

Thanks @Gio

 

I guess I got one more question regarding the sockets for anyone who can answer.

 

Say I got 2 people in a room.

 

How can I get the socket.id of a certain position or index of a certain room.

 

Since my game only needs 2 players per room, when "player 1" sends a command, I would like to emit a message saying its "player 1" sending the command back to "game players" instead of there socket.id which I am currently using and checking if the socket id is them on client. Sending 1 or 2 which would represent the player would shorten the socket length when dispatching to room.