下载websocket包

$ go get golang.org/x/net/websocket 

如果下载失败,可能是被墙了。

package golang.org/x/net/websocket: unrecognized import path “golang.org/x/net/websocket” (https fetch: Get https://golang.org/x/net/websocket?go-get=1: dial tcp 216.239.37.1:443: connectex: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.)

可以尝试

$ go get -u github.com/golang/net/websocket

下载后记得将路径改成golang.org/x/net/websocket

$ cd $GOPATH
$ mkdir -p golang.org/x/net
$ cp github.com/golang/net/websocket/  golang.org/x/net/ -R

实例

服务端代码

server.go

package main

import (  

    "fmt"   

    "golang.org/x/net/websocket" 

    "html/template"              //支持模板html  

    "log"  

    "net/http"  

)

func Echo(ws *websocket.Conn) {  

    var err error  

    for {  

        var reply string  

        //websocket接受信息  

        if err = websocket.Message.Receive(ws, &reply); err != nil {  

            fmt.Println("receive failed:", err)  

            break  

        }

        fmt.Println("reveived from client: " + reply)

        msg := "received:" + reply

        fmt.Println("send to client:" + msg)

        //这里是发送消息

        if err = websocket.Message.Send(ws, msg); err != nil {

            fmt.Println("send failed:", err)

            break

        }

    }

}

func web(w http.ResponseWriter, r *http.Request) {  

    //打印请求的方法  

    fmt.Println("method", r.Method)  

    if r.Method == "GET" { //如果请求方法为get显示login.html,并相应给前端  

        t, _ := template.ParseFiles("websocket.html")  

        t.Execute(w, nil)  

    } else {  

        //否则走打印输出post接受的参数username和password  

        fmt.Println(r.PostFormValue("username"))  

        fmt.Println(r.PostFormValue("password"))  

    }  

}

func main() {

    //接受websocket的路由地址

    http.Handle("/websocket", websocket.Handler(Echo))

    //html页面

    http.HandleFunc("/web", web)

    if err := http.ListenAndServe(":1234", nil); err != nil {

        log.Fatal("ListenAndServe:", err)

    }

}

客户端代码

websocket.html

<!DOCTYPE html>

 <html>

<head>

    <meta charset="utf-8"/>

    <title>go测试socket</title>

</head>

<body>

    <script type="text/javascript">

        var sock = null;

        var wsuri = "ws://127.0.0.1:1234/websocket";

        window.onload = function() {

            console.log("onload");

            sock = new WebSocket(wsuri);

            sock.onopen = function() {

                console.log("connected to " + wsuri);

            }

            sock.onclose = function(e) {

                console.log("connection closed (" + e.code + ")");

            }

            sock.onmessage = function(e) {

                console.log("message received: " + e.data);

            }

        };

        function send() {

            var msg = document.getElementById('message').value;

            sock.send(msg);

        };

    </script>

    <h1>WebSocket Echo Test</h1>

    <form>

        <p>

            Message: <input id="message" type="text" value="Hello, world!">

        </p>

    </form>

    <button onclick="send();">Send Message</button>

</body>

</html>

测试

启动服务端

$ ./server

这里写图片描述

网络通信内容如图所示,首先加载页面,接着使用HTTP建立websocket连接,后续通信直接使用websocket进行。

点击 页面中SendMessage按钮

server端输出:

method GET
reveived from client: Hello, world!
send to client:received:Hello, world!

浏览器输出:

这里写图片描述

参考