Go语言标准包里面没有提供对WebSocket的支持,但是在由官方维护的go.net子包中有对这个的支持,需要独立下载。

Go websocket package 下载地址:
http://code.google.com/p/go.net/websocket

Go get 命令下载:
go get code.google.com/p/go.net/websocket

Go实现的WebSocket的文档:
http://godoc.org/code.google.com/p/go.net/websocket

WebSocket官网提供了一个webSocket测试地址:
http://www.websocket.org/echo.html
在这里输入 websocket的地址就可以进行测试。

Go服务器端源码:

  1. package main
  2. import (
  3. "code.google.com/p/go.net/websocket"
  4. "fmt"
  5. "log"
  6. "net/http"
  7. )
  8. func Echo(ws *websocket.Conn) {
  9. var err error
  10. for {
  11. var reply string
  12. if err = websocket.Message.Receive(ws, &reply); err != nil {
  13. fmt.Println("Can't receive")
  14. break
  15. }
  16. fmt.Println("Received back from client: " + reply)
  17. msg := "Received: " + reply
  18. fmt.Println("Sending to client: " + msg)
  19. if err = websocket.Message.Send(ws, msg); err != nil {
  20. fmt.Println("Can't send")
  21. break
  22. }
  23. }
  24. }
  25. func main() {
  26. fmt.Println("begin")
  27. http.Handle("/", http.FileServer(http.Dir("."))) // <-- note this line
  28. http.Handle("/socket", websocket.Handler(Echo))
  29. if err := http.ListenAndServe(":1234", nil); err != nil {
  30. log.Fatal("ListenAndServe:", err)
  31. }
  32. fmt.Println("end")
  33. }

测试的网页:

  1. <!DOCTYPE html>
  2. <meta charset="utf-8" />
  3. <title>WebSocket Test</title>
  4. <script language="javascript"type="text/javascript">
  5. var wsUri ="ws://localhost:1234/socket";
  6. //var wsUri = "ws://localhost/socket";
  7. //var wsUri = "ws://echo.websocket.org";
  8. var output;
  9. function init() {
  10. output = document.getElementById("output");
  11. testWebSocket();
  12. }
  13. function testWebSocket() { websocket = new WebSocket(wsUri);
  14. websocket.onopen = function(evt) { onOpen(evt) };
  15. websocket.onclose = function(evt) { onClose(evt) };
  16. websocket.onmessage = function(evt) { onMessage(evt) };
  17. websocket.onerror = function(evt) { onError(evt) }; }
  18. function onOpen(evt) { writeToScreen("CONNECTED"); doSend("WebSocket rocks"); }
  19. function onClose(evt) {
  20. writeToScreen("DISCONNECTED"); }
  21. function onMessage(evt) {
  22. writeToScreen('<span style="color: blue;">RESPONSE: '+ evt.data+'</span>');
  23. websocket.close(); }
  24. function onError(evt) {
  25. writeToScreen('<span style="color: red;">ERROR:</span> '+ evt.data); }
  26. function doSend(message) {
  27. writeToScreen("SENT: " + message);
  28. websocket.send(message); }
  29. function writeToScreen(message) {
  30. var pre = document.createElement("p");
  31. pre.style.wordWrap = "break-word";
  32. pre.innerHTML = message; output.appendChild(pre); }
  33. window.addEventListener("load", init, false);
  34. </script>
  35. <h2>WebSocket Test</h2>
  36. <div id="output"></div>
  37. </html>

注意,测试时候 测试html网页是需要在 http://localhost:1234/test.html 这样的地址进行测试。
如果用 file://localhost/Users/cybercare/go/src/websocket/test.html 测试会报错误。
Chrome浏览器可能会抛出400错误,是因为它认为你正在尝试做一个跨域请求WebSocket。即它认为你没有跨域请求的权限。You should host your html+javascript on http:// (or https://), not file://
每日一库之100:websocket - 图1
Static html page created the WebSocket connection golang server directly
http://stackoverflow.com/questions/15884480/static-html-page-created-the-websocket-connection-golang-server-directly

Go websocket server not working with browser
https://groups.google.com/forum/?fromgroups=#!topic/golang-nuts/pNYy5brIF6E

不过如果使用 file://localhost/Users/cybercare/go/src/websocket/test.html 访问访问
var wsUri = “ws://echo.websocket.org”; 则不会有任何问题,而访问 var wsUri = “ws://localhost:1234/socket”; 就会报上面错误:

使用

打开 chrome://net-internals/#events, 输入ws进行过滤,其中的 SOCKET_STREAM 信息如下:
下面是本地静态文件请求 ws://echo.websocket.org/ 的信息截屏。
每日一库之100:websocket - 图2
Websockets?https://groups.google.com/forum/?fromgroups=#!topic/golang-nuts/2QwiBb7ZgrA
本地静态文件请求 ws://localhost:1234/socket 提示错误: HTTP/1.1 400 Bad Request 的信息监控。
每日一库之100:websocket - 图3

这是因为 我们用的这个 websocket 框架 在处理请求的 Origin 时,把它当URL来处理,而本地静态文件发送上来的Origin是null。这里解析错误就会报400错误。
go 官方的这个Orgin解析代码我们可以在下面地址看到(536行):
https://code.google.com/p/go/source/browse/websocket/hixie.go?repo=net#536

每日一库之100:websocket - 图4

https://code.google.com/p/go/source/browse/websocket/server.go?spec=svn.net.9c2295dac419afbe918298a9c90f49786819b569&repo=net&r=2513e900821392c12653a526c6e36a2d3db4da5c#28

参考资料

go-websocket-sample
https://github.com/ukai/go-websocket-sample
Can’t connect to Server through Chrome.
https://code.google.com/p/go/issues/detail?id=3987
Go WebSocket开发
http://www.cnblogs.com/yjf512/archive/2013/02/18/2915171.html
8.2 WebSocket
https://github.com/astaxie/build-web-application-with-golang/blob/master/ebook/08.2.md
广泛意思上的websocket包
http://bbs.mygolang.com/thread-330-1-1.html
golang websocket总结(问题贴)
http://blog.csdn.net/lxy15329/article/details/8737912
基于Golang的WebSocket Server
http://www.xinze.me/%E5%9F%BA%E4%BA%8Egolang%E7%9A%84websocket-server/