server.js

var html = require('fs').readFileSync(__dirname+'/index.html');
var server = require('http').createServer(function(req, res){
    res.end(html);
});
server.listen(1337);

var nowjs = require("now");
var everyone = nowjs.initialize(server);
var clients = {}; // Attention ne pas initialiser avec [] car bug lors de la transmission de la variable au client

everyone.now.newClient = function(name){
    //On ajoute le client au tableau en renseignant son pseudo et son statut (connecté ou non)
    clients[this.user.clientId] =  { login: name, statut: 1};
    // On met à jour la liste des connectés
    for(var c in clients) {
        nowjs.getClient(c, function(err) {
            this.now.updateClientList(clients);
        });
    }
};

everyone.now.openChat = function(idClient){
    var idChat = idClient+this.user.clientId;
    var newChat = nowjs.getGroup(idChat);
    newChat.addUser(this.user.clientId);
    newChat.addUser(idClient);
    newChat.now.addChat(idChat,idClient,clients[idClient].login,clients[this.user.clientId].login);
};

everyone.now.sendMessage = function(message, room){
    var group = nowjs.getGroup(room);
    var idSender = this.user.clientId;
    group.count(function (ct) {
        if(ct <= 1) group.now.displayMessage(room, "Your friend isn't connected");
        else group.now.displayMessage(room, clients[idSender].login+': '+clean(message));
    });
};

nowjs.on('disconnect', function() {
    for(var i in clients) {
        if(i == this.user.clientId) {
            delete clients[i];
            break;
        }
    }
    for(var i in clients) {
        nowjs.getClient(i, function(err) {
            this.now.updateClientList(clients);
        });
    }
});

function clean(html){
    return String(html).replace(/&(?!\w+;)/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;');
}