var net = require('net');
var server = net.createServer();
//聚合所有客戶端
var sockets = [];
//接受新的客戶端連接
server.on('connection', function(socket){
 console.log('got a new connection');
 sockets.push(socket);
 //從連接中讀取數據
 socket.on('data', function(data){
 console.log('got data:', data);
 //廣播數據
 //每當一個已連接的用戶輸入數據，就將這些數據廣播給其他所有已連接的用戶
 sockets.forEach(function(otherSocket){
 if (otherSocket !== socket){
 otherSocket.write(data);
 }
 });
 //刪除被關閉的連接
 socket.on('close', function(){
 console.log('connection closed');
 var index = sockets.indexOf(socket);
 sockets.splice(index, 1);
 });
 });
});
server.on('error', function(err){
 console.log('Server error:', err.message);
});
server.on('close', function(){
 console.log('Server closed');
});
server.listen(4000);

var net = require('net');
var port = 4000;
var quitting = false;
var conn;
var retryTimeout = 3000; //三秒，定義三秒后重新連接
var retriedTimes = 0; //記錄重新連接的次數
var maxRetries = 10; //最多重新連接十次
process.stdin.resume(); //process.stdin流來接受用戶的鍵盤輸入，這個可讀流初始化時處于暫停狀態，調用流上的resume()方法來恢復流
process.stdin.on('data', function(data){
 if (data.toString().trim().toLowerCase() === 'quit'){
 quitting = true;
 console.log('quitting');
 conn.end();
 process.stdin.pause();
 } else {
 conn.write(data);
 }
});
//連接時設置最多連接十次，并且開啟定時器三秒后再連接
(function connect() {
 function reconnect() {
 if (retriedTimes >= maxRetries) {
 throw new Error('Max retries have been exceeded, I give up.');
 }
 retriedTimes +=1;
 setTimeout(connect, retryTimeout);
 }
 conn = net.createConnection(port);
 conn.on('connect', function() {
 retriedTimes = 0;
 console.log('connect to server');
 });
 conn.on('error', function(err) {
 console.log('Error in connection:', err);
 });
 conn.on('close', function() {
 if(! quitting) {
 console.log('connection got closed, will try to reconnect');
 reconnect();
 }
 });
 //打印
 conn.pipe(process.stdout, {end: false});
})();