【Golang 即时通讯系统V2】用户上线及广播功能

user.go

package main

import "net"

type User struct {
	Name string
	Addr string
	C    chan string
	conn net.Conn
}

// 创建一个用户的API
func NewUser(conn net.Conn) *User {
	userAddr := conn.RemoteAddr().String()
	user := &User{
		Name: userAddr,
		Addr: userAddr,
		C:    make(chan string),
		conn: conn,
	}
	// 启动监听当前user channel消息的goroutine
	go user.ListenMessage()
	return user
}

// 监听当前user channel的方法，一旦有消息就直接发送给客户端
func (this *User) ListenMessage() {
	for {
		msg := <-this.C
		this.conn.Write([]byte(msg + "\n"))
	}
}

server.go

package main

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

type Server struct {
	Ip   string
	Port int
	// 在线用户的列表
	OnlineMap map[string]*User
	mapLock   sync.RWMutex
	// 消息广播的channel
	Message chan string
}

// 创建一个server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
}

// 监听Message广播消息channel的goroutine，一旦有消息就发送给全部的在线User
func (this *Server) ListenMessager() {
	for {
		msg := <-this.Message
		// 将message发送给全部的在线user
		this.mapLock.Lock()
		for _, cli := range this.OnlineMap {
			cli.C <- msg
		}
		this.mapLock.Unlock()
	}
}

// 广播消息的方法
func (this *Server) Broadcast(user *User, msg string) {
	sendMsg := "[" + user.Addr + "]" + user.Name + ":" + msg
	this.Message <- sendMsg
}

func (this *Server) Handler(conn net.Conn) {
	// 当前连接的业务
	fmt.Println("连接建立成功")
	// 用户上线,将用户加入到OnlineMap中
	user := NewUser(conn)
	this.mapLock.Lock()
	this.OnlineMap[user.Name] = user
	this.mapLock.Unlock()
	// 广播当前用户上线消息
	this.Broadcast(user, "已上线")
	// 当前hander阻塞
	select {}
}

// 启动服务的接口
func (this *Server) Start() {
	// socket listen
	listener, err := net.Listen("tcp", fmt.Sprintf("%s:%d", this.Ip, this.Port))
	if err != nil {
		fmt.Println("net.listen err:", err)
		return
	}
	// close listen socket
	defer listener.Close()

	// 启动监听message的goroutine
	go this.ListenMessager()
	for {
		// accept
		conn, err := listener.Accept()
		if err != nil {
			fmt.Println("accept err:", err)
			continue
		}
		// do handle
		go this.Handler(conn)
	}

}