go 及时通信-用户消息广播

package main

import (
	"fmt"
	"io"
	"net"
	"sync"
)

//构件server
type Server struct {
	Ip   string
	Port int

	//在线用户列表
	OnlineMap map[string]*User
	MapLock   sync.RWMutex
	//消息
	Message chan string
}

//提供一个对外的接口
func NewServer(ip string, port int) *Server {

	server := &Server{
		Ip:   ip,
		Port: port,

		OnlineMap: make(map[string]*User),
		Message:   make(chan string),
	}

	return server
}

//发送消息
func (this *Server) BroadCast(user *User, msg string) {
	sendMsg := "[" + user.Addr + "]" + ":" + msg

	this.Message <- sendMsg
}

func (this *Server) Handler(conn net.Conn) {
	// fmt.Println("链接成功")

	user := NewUser(conn)

	//用户上线
	this.MapLock.Lock()
	this.OnlineMap[user.Addr] = user
	this.MapLock.Unlock()

	//发送消息
	this.BroadCast(user, "shangxianle")

	//接收客户端消息并发送
	go func() {
		buf := make([]byte, 5000)

		for {
			//读取输入
			n, err := conn.Read(buf)
			if n == 0 {
				//用户下线
				this.BroadCast(user, "xianxianle")
				return
			}
			if err != nil && err != io.EOF {
				fmt.Println("conn read err:", err)
				return
			}

			msg := string(buf)
			this.BroadCast(user, msg)
		}

	}()

	//阻塞
	select {}
}

//监听channel
func (this *Server) ListMessager() {
	for {
		msg := <-this.Message
		//发送每个用户channel
		this.MapLock.Lock()
		for _, cli := range this.OnlineMap {
			cli.C <- msg
		}
		this.MapLock.Unlock()
	}
}

//启动
func (this *Server) start() {

	//监听客户端
	listener, err := net.Listen("tcp", fmt.Sprintf("%s:%d", this.Ip, this.Port))
	if err != nil {
		fmt.Println("listener err:", err)
		return
	}

	//关闭
	defer listener.Close()

	go this.ListMessager()

	for {
		//连接
		conn, err := listener.Accept()
		if err != nil {
			fmt.Println("conn err:", err)
			continue
		}

		//启动go handler操作
		go this.Handler(conn)
	}
}