koa和socket.io的简单流程分析：1.服务端触发初始化io.on('connection',socket=>{});2、客户端发送saysessionsocket.emit('say','我是客户端');3、服务端监听saysessionsocket.on('say',data=>{});4.服务器发送消息会话socket.emit('message',{hello:'Whoareyou'});5.客户端收到消息socket.on('message',(data)=>{});服务器：constkoa=require('koa');constapp=newkoa();constserver=require('http').Server(app.callback())constio=require('socket.io')(server);constport=8081;server.listen(process.env.PORT||端口,()=>{console.log(`apprunat:http://127.0.0.1:${port}`);})io.on('connection',socket=>{console.log('socket初始化完成');socket.on('say',data=>{console.log(data,'收到消息')socket.emit('message',{hello:'你是谁'})})})客户端
