TCP server & client

client.js

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


var client = net.connect(3000, '127.0.0.1');

var log = fs.createWriteStream('out.log');
log.on('error', function(err) {
  console.log(err);
})
client.setEncoding('utf8');
process.stdin.resume();
client.on('connect', function(conn) {
  client.pipe(process.stdout);
  process.stdin.pipe(client);
  client.pipe(log);
  process.stdin.pipe(log);
})

client.on('close', function(data) {
  console.log('connection lost');
  log.close();
  process.exit();
})

server.js

var net = require('net');

var count = 0;
var users = {};


var server = net.createServer(function(conn) {
  var nick;
  function broadcast (msg, exceptMySelf) {
    Object.keys(users).forEach(function(name) {
      if (exceptMySelf && nick === name) return;
      users[name].write(msg);
    })
  }
  conn.write(
    '\n > Welcome to \033[92mnode-chat\033[39m!' +
    '\n > ' + count + ' peole are connected currently' +
    '\n > type your name and press enter :'
  );
  count++;
  conn.setEncoding('utf8');
  conn.on('data', function(data) {
    if (!nick) {
      nick = data.replace('\n', '');
      if (users[nick]) {
        conn.write('nickname \033[90m' + nick + '\033[39m have been used, type another one:');
        nick = '';
      } else {
        users[nick] = conn;
        broadcast('\033[95m > user ' + nick + ' have logged in\033[39m\r\n');
      }
    }
    else {
      broadcast('\033[95m' + nick + '\033[39m: ' + data, true);
    }
  })
  conn.on('close', function() {
    count--;
    delete users[nick];
    broadcast('\033[95m > user ' + nick + ' have logged out\033[39m\r\n');
  })
})

server.listen(3000, function() {
  console.log('\033[95m server started \033[39m');
})