[GO]併發實現聊天室服務器

package main

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

type Client struct {
   C chan string //用戶發送數據的通道
   Name string //用戶名
   Addr string //網絡地址
}

//保存在線用戶 cliaddr ======> client
var onlineMap map[string]Client

var message = make(chan string)

func WriteMsgToClient(cli Client, conn net.Conn)  {
   for msg := range cli.C {
      //給當前客戶端發送信息
      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)  { //處理用戶鏈接
   defer conn.Close()
   //獲取客戶端的網絡地址
   cliAddr := conn.RemoteAddr().String()
   //建立一個結構體
   cli := Client{make(chan string), cliAddr, cliAddr}
   //把結構體添加到map
   onlineMap[cliAddr] = cli

   //新開一個協程，專門給當前客戶端發送信息
   go WriteMsgToClient(cli, conn)

   //廣播某我的在線
   message <- MakeMsg(cli, "login")

   //提示，我是誰
   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 { //對方斷開，或者出問題
            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) //當前用戶從map移除
         message <- MakeMsg(cli, "log out") //廣播誰下線了
         return
      case <- hasData:
         //不作操做
      case time.After(60*time.Second): //60秒都沒有操做了，超時
         delete(onlineMap, cliAddr) //當前用戶從map移除
         message <- MakeMsg(cli, "tiem out") //廣播誰下線了
         return 
      }
   }
}

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

   for true {
      msg := <-message //沒有消息前，這裏會阻塞
      //遍歷map,給map每一個成員都發送此消息
      for _, cli := range onlineMap{
         cli.C <- msg
      }
   }

}

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

   //新開一個協程，用於轉發消息，只要有消息到達 ，那就遍歷map而後給map每一個成員都發送消息
   go Manager()

   //主協程，循環阻塞等待用戶鏈接
   for true {
      conn, err := listener.Accept()
      if err != nil {
         fmt.Println("listener.Accept err = ", err)
         continue //若是這個不發，説不定還有下個發呢
      }
      //處理用戶的鏈接
      go HandleConn(conn)
   }
}

執行的結果，當有任何一個新用戶登陸了，其餘全部的用戶都會收到登陸提醒，這裏以ip加端口號的試作爲一個惟一標識