javascript - 简单和基本的 Node WebSocket 客户端和服务器示例

Question

我正在寻找一个非常基本的 websocket 示例服务器，它可以从套接字进行升级和读取日期。目前我面前有 RFC 6455 并且正在研究它，但有兴趣看看是否有一个简单的示例/源项目可供我查看。

我目前一直在 WS 和 Socket.io 源代码中，但它们有点密集

Answer 1

也许这可以帮助其他人寻找 websocket 服务器的简单示例。这只会读取 126 个字节，并且充满了控制台日志以了解正在发生的事情。我浏览了 RFC 6455 文档以了解如何阅读框架。

  0                   1                   2                   3
  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 +-+-+-+-+-------+-+-------------+-------------------------------+
 |F|R|R|R| opcode|M| Payload len |    Extended payload length    |
 |I|S|S|S|  (4)  |A|     (7)     |             (16/64)           |
 |N|V|V|V|       |S|             |   (if payload len==126/127)   |
 | |1|2|3|       |K|             |                               |
 +-+-+-+-+-------+-+-------------+ - - - - - - - - - - - - - - - +
 |     Extended payload length continued, if payload len == 127  |
 + - - - - - - - - - - - - - - - +-------------------------------+
 |                               |Masking-key, if MASK set to 1  |
 +-------------------------------+-------------------------------+
 | Masking-key (continued)       |          Payload Data         |
 +-------------------------------- - - - - - - - - - - - - - - - +
 :                     Payload Data continued ...                :
 + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +
 |                     Payload Data continued ...                |
 +---------------------------------------------------------------+

server.js [Node.js v7.2.1]:

//Require Build In
const http = require('http');
const fs = require('fs');
const crypto = require('crypto');

//My Consts
const hostname = '127.0.0.1';
const port = 3000;
const webSocketMagicString = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11';

//Create Server
const server = http.createServer((requestIncoming, responseOutGoing) => {
    responseOutGoing.statusCode = 200;
    responseOutGoing.setHeader('Contenet-Type', 'text/html');

    fs.readFile('index.html', function(error, content){ 
        responseOutGoing.end(content);
    });


});

server.listen(port, hostname, () => {
    console.log(`Server is online on http://${hostname}:${port}`);
});

server.on('upgrade', (request, socket, head) => {
    var secWebSocketKey = request.headers['sec-websocket-key'] + webSocketMagicString;
    var hashedKey = crypto.createHash('SHA1').update(secWebSocketKey).digest('base64');

    //Send Back to requester
    socket.write( 
          'HTTP/1.1 101 Switching Protocols\r\n'
        + 'Upgrade: WebSocket\r\n'
        + 'Connection : Upgrade\r\n'
        + 'Sec-WebSocket-Accept:'+hashedKey+'\r\n' + '\r\n'
    );


    //Start Keeping an Eye out for Data
    socket.on('data', (data) => {
        console.clear();
        console.log('Receiving Message:', data);
        var isFinished = data[0] & 127;
        var optionCode = data[0] & 15;
        var isMasked = data[1] >> 7;
        var dataLength = data[1] & 127;
        console.log('Is Finished: ' + isFinished);
        console.log('Is Masked: ' + isMasked);
        console.log('Option Code: ' + optionCode);
        console.log('Data Length: ' + dataLength);
        if(optionCode === 1 && isFinished === 1 && isMasked === 1 && dataLength < 127){
            var maskingKey = data.slice(2, 6);
            var maskedData = data.slice(6, 6+dataLength);
            var unMaskedData = '';
            for(var i = 0; i < dataLength; i++){
                unMaskedData += String.fromCharCode(maskedData[i] ^ maskingKey[i % 4]);
            }
            console.log('unMaskedData: ' + unMaskedData);
            echoTextMessage(socket, unMaskedData);
        }
    });
});

function echoTextMessage(socket, str){
    var response = [129, str.length];
    for(var i = 0; i < str.length; i ++){
        response.push(str.charCodeAt(i));
    }
    console.log(response);
    socket.write(new Buffer(response));
}

index.html

<script>
    var ws = new WebSocket('ws://127.0.0.1:3000');
    ws.onopen = function(){
        console.log('Connected to 127.0.0.1:3000!');
    }
    ws.addEventListener("message", function(event) {
        console.log('Received: ' + event.data);
    });

    sendMessage = (text = 'test') => {
        console.log('Sent: ' + text)
        ws.send(text);
    }
</script>