node.js - Atuthentication with socket io in android for chatting app -

i developing 1 one chatting app socket.io in android. can send & receive messages single chat room. following this tutorial. apps chat module looks that. now, want sent & receive message single user.

during development, observed each , every socket connection , socket.io gives client new id looks :

/#iyq7lakzlclf7g3daaaa 

for reasons can't track specific user send message.

qs 1. have connect database storing user credential send message specific user & send offline message him/her? chatting feature additional function in android app. app uses token based authentication.

i novice in node js & socket.io. give me architectural guideline how solve this. tia.

my app.js code :

var express = require('express'); var app = express(); var server = require('http').createserver(app); var io = require('socket.io')(server);   var port = process.env.port || 3000;  server.listen(port, function () {     console.log('server listening @ port %d', port); });  // routing app.use(express.static(__dirname + '/public'));  // chatroom var numusers = 0; var clients = [];  io.on('connection', function (socket) {     var addeduser = false;     clients.push(socket);      console.log('one user connected: user name: ' +socket.username +"------ id : >> "+ socket.id);     console.log('total user list:' + clients);      socket.on('connect', function (data) {         // tell client execute 'new message'         socket.broadcast.emit('connect', {             username: socket.username,             numusers: numusers,             socket_id:socket.id         });     });      // when client emits 'new message', listens , executes     socket.on('new message', function (data) {         // tell client execute 'new message'         socket.broadcast.emit('new message', {             username: socket.username,             message: data         });     });      // when client emits 'add user', listens , executes     socket.on('add user', function (username) {         if (addeduser) return;          // store username in socket session client         socket.username = username;         ++numusers;         addeduser = true;         socket.emit('login', {             numusers: numusers         });         // echo globally (all clients) person has connected         socket.broadcast.emit('user joined', {             username: socket.username,             numusers: numusers,             socket_id:socket.id         });     });      // when client emits 'typing', broadcast others     socket.on('typing', function () {         socket.broadcast.emit('typing', {             username: socket.username         });     });      // when client emits 'stop typing', broadcast others     socket.on('stop typing', function () {         socket.broadcast.emit('stop typing', {             username: socket.username         });     });      // when want send message specific user     socket.on('say someone', function (id, msg) {          socket.broadcast.to(id).emit('say someone', {             username: socket.username,             id:id,             message: msg         });      });      // when user disconnects.. perform     socket.on('disconnect', function () {          clients.splice(clients.indexof(socket), 1);         console.log('disconnected... ' + socket.id);         if (addeduser) {             --numusers;             // echo globally client has left             socket.broadcast.emit('user left', {                 username: socket.username,                 numusers: numusers             });         }     }); }); 

there problem implementation of socket.on('say someone', function (id, msg)

please see link below

sending message specific id in socket.io 1.0

https://auth0.com/blog/2014/01/15/auth-with-socket-io/