Create a simple real time chat by node.

Client.js

var net = require('net');
var readline = require('readline');

var HOST = process.env.IP,
    PORT = process.env.PORT;

var me = readline.createInterface(process.stdin, process.stdout);
var client = new net.Socket();
client.connect(PORT, HOST, function() {
    console.log('CONNECTED TO: ' + HOST + ':' + PORT);

    // send message to server.
    say(client, 'Please enter your name:');
});

client.on('data', function(data) {
    me.write(null, {ctrl: true, name: 'u'});
    me.pause();
    console.log(data.toString('utf-8'));
    me.resume();
    me.prompt();
});

function say(client, title) {
    me.question(title +'\t', function(data) {
        if(data == 'quit') {
            me.close();
            client.destroy();
            return;
        }
        if(data == '') {
            say(client, title);
        } else {
            client.write(data);
            say(client, 'me>');
        }
    });
}

client.on('close', function() {
    console.log('Connection closed');
});

client.on('error', function() {
    console.log('Connected error!')
    process.exit(0);
})

process.on('SIGINT', function() {
  console.log('Exit');
  client.end();
});

Server.js

var net = require('net');
var host = process.env.IP,
    port = process.env.PORT;
var clients = [];
var server = net.createServer(function(sock) {
    // socket客户端标识
    sock.name = sock.remoteAddress + ':' + sock.remotePort;
    if(clients.indexOf(sock) == -1) {
        console.log('hello' + sock.name);
        // 添加到客户端数组
        clients.push(sock);
    }

    // 广播消息欢迎消息
    broadcast(sock, 'Welcome ' + sock.name);
    // 为这个socket实例添加一个"data"事件处理函数
    sock.on('data', function(data) {
        broadcast(sock, sock.name + ' > ' + data);
    });

    // 为这个socket实例添加一个"close"事件处理函数
    sock.on('close', function(data) {
        broadcast(sock, sock.name + "## exit");
        clients.slice(clients.indexOf(sock), 1);
    });

    sock.on('error', function(err) {
        console.log(sock.name + " : " + err.message);
    });

    // 广播消息
    function broadcast(sender, message) {
        message = "\n" + message;
        clients.forEach(function(sock){
            if( sock == sender) {
                return;
            }
            sock.write(message);
        });
        process.stdout.write('BroadCast:' + message);
    }

}).listen(port, host);

console.log('Server listening on ' + host +':'+ port);