go语言:200行代码做udp rtp转发并发分布服务器

使用go做服务器

最近写服务器使用c++多了以后，java和node逐渐被放到一边，最后又做了一个决定，使用go来做服务器，将会使用200行代码不到来做这个并发和分布式服务器，为什么？

go语言的优势

前面的文章有我的所见：看这个go语言优势和使用结构体与链表

以下内容还没有完全完成，需要继续修改…敬请关注

流程

udpserver就是我们要做的转发服务
httpserver是我们的信令服务

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接受链接

接受询问

udpserver

RTP和文字聊天转发

httpserver

返回udpserver的地址和认证code

就这样简单

show me the code

主体代码没有完全完成，但已经成型

package main
import ("io""fmt""net""net/http""os""log""container/list"
)type s_client struct{num intname string*net.UDPAddr
}var g_client = list.New()
//var g_clients map[uint]list //uint 是ssrc，list是请求的链表
var limitChan = make(chan bool, 1000)
// hello world, the web server
func HelloServer(w http.ResponseWriter, req *http.Request) {//返回服务器的端口地址，可以有多个服务器来进行负载均衡io.WriteString(w, "127.0.0.1:8080")
}
// UDP goroutine concurrency to read UDP maybe not parallelism,maybe in onethread maybe in multi thread,maybe yes,maybe no
func udpProcess(conn *net.UDPConn)  {data := make([]byte, 1024)n,remoteAddr,err := conn.ReadFromUDP(data)if err != nil {fmt.Println("Failed To Read UDP Msg, Error: " + err.Error())}//var flag = 0x80if(data[0] == 0x80){//RTP 协议if n < 13 {fmt.Println("client error")}else {//转发conn.WriteToUDP([]byte("test"), remoteAddr)}//求取RTP ssrc}//Call Endc Resp Readstr :=string(data[0:3])if str == "Call" { //单点找人}else if str=="Pull" {//拉取流fmt.Println("pull")//ssrc := 1234//l := list.New()//l.PushBack(s_client{1,"name",remoteAddr})//g_clients[ssrc] = lg_client.PushBack(s_client{1,"name",remoteAddr})}else if str=="Resp" {//}else if str == "Chat" {}else if str == "Endc" {}else {}//str := string(data[:n])//fmt.Println("Reveive From Client, Data: " + str)<- limitChan
}func udpServer(address string)  {fmt.Println("server start at udp 8080")udpAddr, err := net.ResolveUDPAddr("udp", address)conn, err := net.ListenUDP("udp", udpAddr)defer conn.Close()if err != nil {fmt.Println("Read From Connect Failed, Err :" + err.Error())os.Exit(1)}for {limitChan <- truego udpProcess(conn)}}func httpServer(address string) {http.HandleFunc("/push", HelloServer)fmt.Println("server http start at 8080")err := http.ListenAndServe(":8080", nil)if err != nil {log.Fatal("ListenAndServe: ", err)}
}func main() {//g_clients :=make(map[uint]list)//client[32]="qianbo"address := "0.0.0.0:8080"go httpServer(address)udpServer(address)
}

启动了一个协程来运行httpserver，接受客户端询问，返回udpserver地址，有信令服务器就可以返回多个udpserver中的一个，这样就能打造分布式服务器，udpserver如何转发呢个，客户端知道服务器地址后，使用认证session询问，发包传到服务器一个探测询问包，服务器回传一个包，打通了双方地址，服务器在内网也是可以的，这时候要用stun服务器，这里暂时服务器在外网，使用RTP协议上传数据后，服务器负责转发，客户端存储在链表中，现在代码100行，完成时应该在200行左右，服务器使用协程运行，并发控制在1000，依照服务器能力，可做修改