[GO]并发实现聊天室服务器

package main

import (
   "net"
   "fmt"
   "strings"
   "time"
)

type Client struct {
   C chan string //用户发送数据的通道
   Name string //用户名
   Addr string //网络地址
}

//保存在线用户 cliaddr ======> client
var onlineMap map[string]Client

var message = make(chan string)

func WriteMsgToClient(cli Client, conn net.Conn)  {
   for msg := range cli.C {
      //给当前客户端发送信息
      conn.Write([]byte(msg + "\n"))
   }
}

func MakeMsg(cli Client, msg string) (buf string)  {
   buf = "[" + cli.Addr + "]" + cli.Name + ": login"
   return
}

func HandleConn(conn net.Conn)  { //处理用户连接
   defer conn.Close()
   //获取客户端的网络地址
   cliAddr := conn.RemoteAddr().String()
   //创建一个结构体
   cli := Client{make(chan string), cliAddr, cliAddr}
   //把结构体添加到map
   onlineMap[cliAddr] = cli

   //新开一个协程，专门给当前客户端发送信息
   go WriteMsgToClient(cli, conn)

   //广播某个人在线
   message <- MakeMsg(cli, "login")

   //提示，我是谁
   cli.C <- MakeMsg(cli, "I am here")

   var isQuit = make(chan bool)

   hasData := make(chan bool)

   go func() {
      buf := make([]byte, 2048)
      for true {
         n, err := conn.Read(buf)
         if n == 0 { //对方断开，或者出问题
            isQuit <- true
            fmt.Println("conn.read err = ", err)
            return
         }
         msg := string(buf[:n-1])
         if len(msg) == 3 && msg == "who" {
            conn.Write([]byte("user list : \n"))
            for _, tmp := range onlineMap {
               msg = tmp.Addr + ":" + tmp.Name + "\n"
               conn.Write([]byte(msg))
            }
         }else if len(msg) >= 8 && msg[:6] == "rename" {
            //rename|mike
            name := strings.Split(msg,"|")[1]
            cli.Name = name
            onlineMap[cliAddr] = cli
            conn.Write([]byte("user list :\n"))
         }else {
            message <- MakeMsg(cli, msg)
         }
      }
   }()

   for true {
      select {
      case <- isQuit:
         delete(onlineMap, cliAddr) //当前用户从map移除
         message <- MakeMsg(cli, "log out") //广播谁下线了
         return
      case <- hasData:
         //不做操作
      case time.After(60*time.Second): //60秒都没有操作了，超时
         delete(onlineMap, cliAddr) //当前用户从map移除
         message <- MakeMsg(cli, "tiem out") //广播谁下线了
         return 
      }
   }
}

func Manager()  {
   //给map分配空间map
   onlineMap = make(map[string]Client)

   for true {
      msg := <-message //没有消息前，这里会阻塞
      //遍历map,给map每个成员都发送此消息
      for _, cli := range onlineMap{
         cli.C <- msg
      }
   }

}

func main() {
   //创建监听
   listener, err := net.Listen("tcp", ":8000")
   if err != nil {
      fmt.Println("net.Listen err = ", err)
      return
   }

   //新开一个协程，用于转发消息，只要有消息到达 ，那就遍历map然后给map每个成员都发送消息
   go Manager()

   //主协程，循环阻塞等待用户连接
   for true {
      conn, err := listener.Accept()
      if err != nil {
         fmt.Println("listener.Accept err = ", err)
         continue //如果这个不发，説不定还有下个发呢
      }
      //处理用户的连接
      go HandleConn(conn)
   }
}

执行的结果，当有任何一个新用户登录了，其他所有的用户都会收到登录提醒，这里以ip加端口号的试做为一个唯一标识