var events=require('events')

var net = require('net')

var channel= new events.EventEmitter();//事件发射器

channel.client={};

channel.subscriptions={}

channel.on("join",function(id,client){

    this.client[id]=client;

    console.log("--------------------")

    var that =this;

    this.subscriptions[id]=(senderId,message)=>{

         console.log("broadcast")

            that.client[id].write(message)

    }

    channel.on('broadcast',this.subscriptions[id]);//每当进入一个链接就会在事件环中添加一个监听

})

var server = net.createServer(client=>{

    console.log("--------------------1")

    var id=client.remoteAddress+':'+client.remotePort;

    channel.emit("join",id,client)

    client.on('connect',()=>{//当用户连上

        channel.emit("join",id,client)//第一个参数可以自己定义，只是一个事件的名字，除了error随便用

    })

    client.on('data',data=>{

        data=data.toString();

        channel.emit('broadcast',id,data);

    })

})

server.listen(8888,()=>{

    console.log("I'm listening on port 8888")

})