nodejs 如何使用upgrade，并且C/B 发送消息

Posted 2020-08-25 暗影侠客

 1 const http = require(\'http\');
 2 const querystring = require("querystring");
 3 var postData = querystring.stringify({
 4     \'msg\': \'Hello World!\'
 5 });
 6 // Create an HTTP server
 7 var srv = http.createServer((req, res) => {
 8     res.writeHead(200, {\'Content-Type\': \'text/plain\'});
 9     res.end(\'okay\');
10 });
11 srv.on(\'upgrade\', (req, socket, head) => {
12 
13     socket.write(\'HTTP/1.1 101 Web Socket Protocol Handshake\\r\\n\' +
14         \'Upgrade: WebSocket\\r\\n\' +
15         \'Connection: Upgrade\\r\\n\' +
16         \'\\r\\n\');
17 
18     socket.on("data", (d)=> {
19         console.log(d.toString())
20     });
21     socket.on("end", ()=> {
22         socket.write("发送服务器的消息");
23         socket.end();
24         if (!socket.destroyed) {
25             console.log(" socket.end 会销毁socket,不信你可以执行end，看会不会进入这个方法")
26             if (socket.destroy) {
27                 socket.destroy();
28                 console.log(!socket.destroyed)
29             }
30 
31         }
32     });
33 });
34 
35 // now that server is running
36 srv.listen(1337, \'127.0.0.1\', () => {
37 
38     // make a request
39     var options = {
40         port: 1337,
41         hostname: \'127.0.0.1\',
42         headers: {
43             \'Connection\': \'Upgrade\',
44             \'Upgrade\': \'websocket\'
45         }
46     };
47 
48     var req = http.request(options);
49     req.on(\'upgrade\', (res, socket, upgradeHead) => {
50         socket.write(\'发送客户端的消息\\r\\n\');
51         socket.end();
52 
53         socket.on(\'data\', (chunk) => {
54             console.log(chunk.toString());
55         });
56         socket.on(\'end\', () => {
57             console.log("服务器消息接收完毕");
58             console.log("socket已经被销毁",socket.destroyed)
59         });
60 
61     });
62 
63     req.end();
64 
65 
66 });

整个流程是

  1 ：request的 header里加上:

 \'Connection\': \'Upgrade\',
 \'Upgrade\': \'websocket\'

生成的http.ClientRequest 最后一定要调用end函数，不然服务器会一直等待你消息发送完毕

2: 服务器监听 ‘Upgrade’，然后返回：

\'HTTP/1.1 101 Web Socket Protocol Handshake\\r\\n\' +
    \'Upgrade: WebSocket\\r\\n\' +
    \'Connection: Upgrade\\r\\n\' +
   \'\\r\\n\'


维基百科里说了，这样叫作握手！

 

这样的话，Upgrade 就算建立起来了。

3:然后就可以通过socket相互消息了。记住socket.end一旦执行，就会断开这次的tcp链接了。