golang中使用websocket简单示例

首先导入需要用到的工具包：

go get github.com/gobwas/ws/wsutil
go get github.com/gobwas/ws/

服务端代码示例：

web.go

package main

import (
	"fmt"
	"io"
	"log"
	"net"
	"net/http"

	"github.com/gobwas/ws/wsutil"

	"github.com/gobwas/ws"
)

var n net.Conn

func web(w http.ResponseWriter, r *http.Request) {
	conn, _, _, err := ws.UpgradeHTTP(r, w, nil)
	if err != nil {
		log.Println("连接失败：", err)
	}
	for {
		defer conn.Close()
		var (
			state  = ws.StateServerSide
			reader = wsutil.NewReader(conn, state)//创建一个读取器，从conn中读取状态以保持连接
			writer = wsutil.NewWriter(conn, state, ws.OpText)//创建一个新的缓存数据区,ws.OpText是操作码
		)
		header, _ := reader.NextFrame()//读取conn中的下一条数据
		writer.Reset(conn, state, header.OpCode)//重置缓冲数据区，并给其制定新的操作码
		if _, err := io.Copy(writer, reader); err != nil {//将读取到的数据copy到writer
			fmt.Println("copy err :", err)
		}
		if err := writer.Flush(); err != nil {//Flush将所有缓冲数据写入底层的io.Writer(发送给客户端)
			fmt.Println("Flush err :", err)
		}

	}
}

func main() {
	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		http.ServeFile(w, r, "static/web.html")
	})
	http.HandleFunc("/ws", web)
	http.ListenAndServe(":1234", nil)
}

客户端代码：

web.html

<!-- websockets.html -->
<input id="input" type="text" />
<button onclick="send()">Send</button>
<pre id="output"></pre>
<script>
	var input = document.getElementById("input");
	var output = document.getElementById("output");
	var socket = new WebSocket("ws://localhost:1234/ws");

	socket.onopen = function () {
		output.innerHTML += "Status: Connected\n";
	};

	socket.onmessage = function (e) {
		output.innerHTML += "Server: " + e.data + "\n";
	};

	function send() {
		socket.send(input.value);
		input.value = "";
	}
</script>

访问路径：

效果如图：