40行代码的node群聊系统

var net = require('net');
var count = 0,users={};
var server = net.createServer(function(conn){
    conn.setEncoding('utf8');
    conn.write(
        '\n> welcome to \033[92mnode-chat\033[39m!'+
        '\n> '+count+' other people are connected at this time.'+
        '\n> please write your name and press enter  '
        );
    count++;
    var nickname;
    conn.on('data',function(data){
        data = data.replace('\r\n','');
        if(!nickname){
            if(users[data]){
                conn.write('\033[93m> nickname already in use please try again:\033[39m  ');
                return;
            }else{
                nickname = data;
                users[nickname] = conn;
                broadcast('\033[90m> '+ nickname +' joined the room\033[39m\n');
            }
        }else{
            broadcast('\033[96m > '+nickname+' : \033[39m'+data+'\n');
        }
    });
    function broadcast(msg,exceptMyself){
        for(var key in users){
            if(!exceptMyself||key!= nickname){
                users[key].write(msg);
            }
        }
    }
    conn.on('close',function(){
        count--;
        delete users[nickname];
        broadcast('\033[90m> '+nickname+' left the room\033[39m\n');
    })
});
server.listen(3000,function(){
    console.log('\033[96m    server listening on *:3000\033[39m');
})