javascript - 如何制作过期/签名视频嵌入网址

Question

我是新人，正在学习网络开发等等。我只知道如何将我的视频嵌入网站中，任何菜鸟都可以轻松获得源代码，他们也可以嵌入它。但在许多网站中，视频 src 是使用重定向器链接进行编码的，例如:https://redirector.googlevideo.com/videoplayback?requiressl=yes&id=0c5d32687bb8e7fd&itag=18&source=webdrive&ttl=transient&app=explorer&ip=2604:a880:0:1010::dc7:d001&ipbits=32&expire=1481329545&sparams=requiressl%2Cid%2Citag%2Csource%2Cttl%2Cip%2Cipbits%2Cexpire&signature=8094D8DEF3C98784DC5561980B5725379B61A804.4C63CCB219699C4A2C02FB2606425E50243F8D36&key=ck2&mm=31&mn=sn-ab5l6ne6&ms=au&mt=1481314943&mv=m&nh=IgpwcjA0LmxnYTA3KgkxMjcuMC4wLjE&pl=48

它会在一段时间后过期，在本例中是一天。我了解到这是一个签名网址。

所以，我想知道如何创建这样的签名网址。请不要提供任何插件名称，因为我不是付费用户，也不是我仅使用博客的任何东西。我只是想学习如何用 javascript 编写它。

简而言之，我想让我嵌入的 YouTube 视频的来源成为一个签名网址，该网址在一小时后过期，并且当网站刷新时，来源应该不断变化。

Answer 1

编辑:执行此操作后，我注意到您使用的是 YouTube 视频嵌入内容，而不是实际的视频文件。但没关系，我就把它留在这里......

<小时/>

由于您没有在任何地方提到 NodeJS，我猜您希望在浏览器中使用 JS 来执行此操作。但要在浏览器中实现这一点，您需要将真实的视频 URL 发送到客户端，并向公众公开您的 URL 签名功能。这违背了签名 URL 的目的。

我用PHP尝试了一下，不是很复杂。流程如下:

当用户请求您的页面时，您会为他创建一个临时 URL。此 URL 包含一个签名，其中包含视频的文件路径和到期日期。它会引导至一个页面，该页面将翻译签名，并在一切正确的情况下提供文件。

我发现您不想使用库，但我使用了“自制”库，这将有助于使事情井井有条。这是我使用的文件结构:

/
├── libraries/
│   ├── VideoStream.php
│   └── VideoSignature.php
├── index.php
├── video.mp4
└── getVideo.php

libraries/VideoSignature.php

请注意，您需要更改顶部的设置以满足您的需求

<?php

/*
 * This class allows you to:
 * - Encrypt filepaths and expiration dates into signatures
 * - Decrypt signatures into filepaths and expiration dates
 *
 *
 * Note: String encryption functions were found here:
 * http://stackoverflow.com/a/1289114/1913729
 */

class VideoSignature
{
    // Time before a URL expires, in seconds
    private $expires = 10;
    // Key used to sign your URLs
    private $encryption_key = 'soMeStr0ngP455W0rD!!';
    // Public URL used to serve the content
    private $proxy_url = '/getVideo.php';

    // Encrypts a string
    private function encryptStr($str){
        $iv = mcrypt_create_iv(
            mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC),
            MCRYPT_DEV_URANDOM
        );

        $encrypted = base64_encode(
            $iv .
            mcrypt_encrypt(
                MCRYPT_RIJNDAEL_128,
                hash('sha256', $this->encryption_key, true),
                $str,
                MCRYPT_MODE_CBC,
                $iv
            )
        );

        return $encrypted;
    }

    // Decrypts a String
    private function decryptStr($str){
        $data = base64_decode($str);
        $iv = substr($data, 0, mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC));

        $decrypted = rtrim(
            mcrypt_decrypt(
                MCRYPT_RIJNDAEL_128,
                hash('sha256', $this->encryption_key, true),
                substr($data, mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC)),
                MCRYPT_MODE_CBC,
                $iv
            ),
            "\0"
        );

        return $decrypted;
    }

    // Returns a temporary URL
    public function getSignedURL($filepath){
        $data = json_encode(
                array(
                    "filepath" => $filepath,
                    "expires" => time() + $this->expires
                )
            );

        $signature = $this->encryptStr($data);

        return $this->proxy_url . "?s=" . urlencode($signature);
    }

    // Returns a filepath from a signature if it did not expire
    public function getFilepath($signature){
        $data = json_decode( $this->decryptStr($signature), true);

        if($data !== null && $data['expires'] > time() && file_exists($data['filepath'])){
            return $data['filepath'];
        }

        return false;
    }
}

库/VideoStream.php

<?php

/*
 * This class was found here:
 * http://stackoverflow.com/a/39897793/1913729
 *
 * It allows you to stream video without giving the real file URL
 */

class VideoStream
{
    private $path = "";
    private $stream = "";
    private $buffer = 102400;
    private $start  = -1;
    private $end    = -1;
    private $size   = 0;

    function __construct($filePath) 
    {
        $this->path = $filePath;
    }

    /**
     * Open stream
     */
    private function open()
    {
        if (!($this->stream = fopen($this->path, 'rb'))) {
            die('Could not open stream for reading');
        }

    }

    /**
     * Set proper header to serve the video content
     */
    private function setHeader()
    {
        ob_get_clean();
        header("Content-Type: video/mp4");
        header("Cache-Control: max-age=2592000, public");
        header("Expires: ".gmdate('D, d M Y H:i:s', time()+2592000) . ' GMT');
        header("Last-Modified: ".gmdate('D, d M Y H:i:s', @filemtime($this->path)) . ' GMT' );
        $this->start = 0;
        $this->size  = filesize($this->path);
        $this->end   = $this->size - 1;
        header("Accept-Ranges: 0-".$this->end);

        if (isset($_SERVER['HTTP_RANGE'])) {

            $c_start = $this->start;
            $c_end = $this->end;

            list(, $range) = explode('=', $_SERVER['HTTP_RANGE'], 2);
            if (strpos($range, ',') !== false) {
                header('HTTP/1.1 416 Requested Range Not Satisfiable');
                header("Content-Range: bytes $this->start-$this->end/$this->size");
                exit;
            }
            if ($range == '-') {
                $c_start = $this->size - substr($range, 1);
            }else{
                $range = explode('-', $range);
                $c_start = $range[0];

                $c_end = (isset($range[1]) && is_numeric($range[1])) ? $range[1] : $c_end;
            }
            $c_end = ($c_end > $this->end) ? $this->end : $c_end;
            if ($c_start > $c_end || $c_start > $this->size - 1 || $c_end >= $this->size) {
                header('HTTP/1.1 416 Requested Range Not Satisfiable');
                header("Content-Range: bytes $this->start-$this->end/$this->size");
                exit;
            }
            $this->start = $c_start;
            $this->end = $c_end;
            $length = $this->end - $this->start + 1;
            fseek($this->stream, $this->start);
            header('HTTP/1.1 206 Partial Content');
            header("Content-Length: ".$length);
            header("Content-Range: bytes $this->start-$this->end/".$this->size);
        }
        else
        {
            header("Content-Length: ".$this->size);
        }  

    }

    /**
     * close curretly opened stream
     */
    private function end()
    {
        fclose($this->stream);
        exit;
    }

    /**
     * perform the streaming of calculated range
     */
    private function stream()
    {
        $i = $this->start;
        set_time_limit(0);
        while(!feof($this->stream) && $i <= $this->end) {
            $bytesToRead = $this->buffer;
            if(($i+$bytesToRead) > $this->end) {
                $bytesToRead = $this->end - $i + 1;
            }
            $data = fread($this->stream, $bytesToRead);
            echo $data;
            flush();
            $i += $bytesToRead;
        }
    }

    /**
     * Start streaming video content
     */
    function start()
    {
        $this->open();
        $this->setHeader();
        $this->stream();
        $this->end();
    }
}

index.php

<?php

// Load the signature helper functions
include "libraries/VideoSignature.php";
$vs = new VideoSignature();

?><!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Check out my video!</title>
</head>
<body>
    <!-- /!\ Here, you need to insert a path to your video,
         relative to the getVideo.php file, not an actual URL! -->
    <video src="<?=$vs->getSignedURL("server/path/to/video.mp4");?>"></video>
</body>
</html>

getVideo.php

<?php

// Load the signature helper functions
include "libraries/VideoSignature.php";
$vs = new VideoSignature();
// Load the video streaming functions
include "libraries/VideoStream.php";


if(isset($_REQUEST['s']) && $filepath = $vs->getFilepath($_REQUEST['s'])){
    $stream = new VideoStream($filepath);
    $stream->start();
} else {
    header("HTTP/1.0 403 Forbidden");
    echo "This URL has expired.";
}