[Node.js] How to keep all connections connected with this server app

Hi guys,

I'm not sure if this the right place to ask. Since I cannot post it on Google Group I would post it here in hope someone can help me out.

Below is my simple node.js server app. It broadcasts message from a sending user to all connected users. However, all connections have been lost if somebody refresh a page. I hope somebody can point out what wrong with my code. How do I keep connections connected.

var WebSocketServer = require('ws').Server;

var wsServer = new WebSocketServer({ port : 8080 }),
    clients = [];

wsServer.on('connection', function(ws) {
    clients.push(ws);

    ws.on('message', function(message, flags) {
        for(var i = 0, j = clients.length; i < j; i += 1) {
            var xx = clients[i];
        }
        if (typeof message === 'string') {
            var json = JSON.parse(message);
            switch(json.type) {
                case "msg":
                    broadcast.data(xx, message);
                    break;
                case "data":
                case "demo":
                    // return;
                    break;
            }
        }
    });

    ws.on('close', function(message) {
        var index = clients.indexOf(ws);
        if (index !== -1) {
            clients.splice(index, 1);
        }
    });
});

// Broadcast messages to all connected clients
var broadcast = {
    data: function(xi, message) {
        var that = this;
        this.xi = xi;
        this.message = message;
        this.data.prototype = function() { that.send(this.xi, this.message); }
        this.data.prototype(this.xi, this.message);
    },
    send: function(){
        this.xi.send(this.message, {
            mask: false
        });
    }
};

Code (markup):

Thanks,

 

Ha ha,
I was able to solve this eventually. What's a challenge Exciting!

 

I would recommend you show us what you did to solve it - it might help other people struggling with the same problem, finding your post on a search. It's customary to include solutions you come up with yourself (with a source if it's pulled from somewhere).

 

OK, this is how I do with my (actually) single page application (not that mile long one). It read file on a server and sent data from there with a lightning speed (believe me, there's a guy trying to send data at a light speed). It helps eliminated the need of page refresh and HTTP request overhead.

The problems were that it has to wait for a handshake and websocket connection to establish and it comes at a cost of server memory. There's problem with SEO though, Uncle Google may not index those information and you lose ranking. I don't care since my files are mostly media.

Aside form that, everything is fine and I'm very happy with it.

If you look at the code below and spot anything I can improve my code it's greatly appreciated. I'm always looking for best practice:
Here it is (security included for a noob interesting in Node.js):

var wsServer = new WebSocketServer({ port : 8080 }),
    clients = [];

    wsServer.on('connection', function(ws) {
        clients.push(ws);

        var domain = ws.upgradeReq.headers.origin;
        if (domain !== 'http://mywebsite.com') {
            return;
        }

        ws.on('message', function(message, flags) {     
            if (typeof message === 'string') {
                var json = JSON.parse(message);
                switch(json.type) {
                    case "msg":
                        var req = json.data.request,
                        user = json.data.user;
                        fs.readFile(__dirname + '/files/' + req, 'utf-8', function(err,data){
                            if (err) { return console.log(err); }
                            var cont = { user: user, data: data },
                                object = JSON.stringify({ type:'script', data: cont });

                            for (var i = 0, j = clients.length; i < j; i += 1) {
                                var z = clients[i],
                                sendIt= new sendData(z);
                            }
                            function sendData(z) {
                                broadcast.data(z, object);
                            }
                        });
                        break;
                    case "data":
                    case "demo":
                        // do something else
                        break;
                }
            }
        });
    });

Code (markup):