server.js

/**
 * JSON FILE READ
 *
 * @version 0.2.1
 * @author PATEL
 */
var http = require('http');
var cluster = require('cluster');
var numCPUs = require('os').cpus().length;
if (cluster.isMaster) {
    // Fork workers.
    console.log('Master cluster setting up ' + numCPUs + ' workers...');

    for (var i = 0; i < numCPUs; i++) {
        cluster.fork();
    }
    cluster.on('online', function (worker) {
        console.log('Worker ' + worker.process.pid + ' is online');
    });

    cluster.on('exit', function (worker, code, signal) {
        console.log('Worker %d died :(', worker.id);
        cluster.fork();
    });
}
else {
    /* START OF APPLICATION */

    var PORT = 2005;
    var FETCH_INTERVAL = 300;
    var express = require('express');
    var io = require('socket.io');
    var app = express();
    var server = http.createServer(app);
    var io = io.listen(server);
    var rooms = [];
    var TimerArr = [];

    server.listen(PORT);

    app.get('/', function (req, res) {
        res.sendFile(__dirname + '/index.html');
    });
    app.use(function (req, res, next) {
        res.header("Access-Control-Allow-Origin", "*");
        res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
        next();
    });
    var Client = 0;
    io.sockets.on('connection', function (socket) {

        ++Client;

        console.log("NEW client connected with socketid " + socket.id);
        console.log("Total user = " + Client);

        socket.on('ticker', function (ticker) {

            socket.room = ticker;
            socket.join(ticker);
            isRoom(socket, ticker);
        });

        socket.on('disconnect', function () {

            --Client;

            console.log("client with socketid  " + socket.id + " is leaved from " + socket.room + "");

            console.log("Total user = " + Client);

            socket.leave(socket.room);

            var myroom = io.sockets.adapter.rooms[socket.room];

            /* if room has no user close room */

            if (myroom) {
                console.log("room " + socket.room + " HAS " + Object.keys(myroom).length + " user");
            }
            else {
                clearTimeout(TimerArr[socket.room]);
                var index = rooms.indexOf(socket.room);
                if (index >= 0) {
                    rooms.splice(index, 1);
                }
                console.log("last closed room " + socket.room);
            }
        });
    });
    function isRoom(socket, ticker) {
        if (rooms.indexOf(ticker) == -1) {
            console.log("new room created is " + ticker);
            readjsonfile(socket, ticker);
            rooms.push(ticker);
        }
        else {
            var old_room = io.sockets.adapter.rooms[ticker];
            console.log("join old room is " + ticker + " HAS " + Object.keys(old_room).length + " user");
        }
    }

    function readjsonfile(p_socket, p_ticker) {
        console.log("NUMBER OF TIMER = " + (TimerArr.length + 1) + " Date = " + Date.now() + " Total user = " + Client);
        TimerArr[p_ticker] = setTimeout(function () {
            var request = http.get({
                    host: '192.168.1.25',
                    port: 80,
                   path: '/' + p_ticker.replace('.', 'a') + '.json'
				  
                },
                function (response) {
                    response.setEncoding('utf8');
                    var data = "";
                    response.on('data', function (chunk) {
                        data += chunk;
                    });

                    response.on('end', function () {
						
						io.sockets.in(p_ticker).emit('quote', data);
                    });

                }).on('error', function (e) {
                console.log("Got error: " + e.message);
            });
            readjsonfile(p_socket, p_ticker);
        }, FETCH_INTERVAL);
    }
}