Javascript - 如何以編程方式獲取Youtube視頻的URL？ （自我回答）

Question

一個非常常見的問題是「如何獲取Youtube視頻的網址？」。大多數答案都涉及到一些視頻頁面的html拼寫和重新編碼，或者訴諸'使用這個第三方工具或網站'。

在任何Youtube視頻頁面的任何瀏覽器中，它都可以通過開發工具控制檯輕鬆完成。

請參閱下面的答案。

Answer 1

例子是在這裏：

https://gist.github.com/geuis/8b1b2ea57d7f9a9ae22f80d4fbf5b97f

// Run from the dev tools console of any Youtube video 
// Accurate as of June 12, 2016 
var videoUrls = {}; 
ytplayer.config.args.url_encoded_fmt_stream_map.split(',').forEach(function (item) { 
    var obj = {}; 

    item.split('&').forEach(function (param) { 
    param = param.split('='); 
    obj[param[0]] = decodeURIComponent(param[1]); 
    }); 

    videoUrls[obj.quality] = obj; 
}); 

console.log(videoUrls); 

爲https://www.youtube.com/watch?v=9bZkp7q19f0

{ 
    "hd720": { 
    "url": "https://r3---sn-n4v7sn76.googlevideo.com/videoplayback?ms=au&mv=m&mt=146577…zA3KgkxMjcuMC4wLjE&ip=108.233.85.171&key=yt6&requiressl=yes&itag=22&cnr=14", 
    "quality": "hd720", 
    "s": "1BEF82C7D9487809555E4B5124CA244FD93857C62.7869EB3FE7E8BE955B85E19F769DD80C49F3A87CB", 
    "itag": "22", 
    "type": "video/mp4;+codecs=\"avc1.64001F,+mp4a.40.2\"" 
    }, 
    "medium": { 
    "url": "https://r3---sn-n4v7sn76.googlevideo.com/videoplayback?ms=au&mv=m&mt=146577…AxLnNqYzA3KgkxMjcuMC4wLjE&ip=108.233.85.171&key=yt6&requiressl=yes&itag=18", 
    "quality": "medium", 
    "s": "35ADDCF2F151540B9AE72455ED9CD079B3A166669.F168091B130653FCACA72506C01625B74E46C1A7D", 
    "itag": "18", 
    "type": "video/mp4;+codecs=\"avc1.42001E,+mp4a.40.2\"" 
    }, 
    "small": { 
    "url": "https://r3---sn-n4v7sn76.googlevideo.com/videoplayback?ms=au&mv=m&mt=146577…AxLnNqYzA3KgkxMjcuMC4wLjE&ip=108.233.85.171&key=yt6&requiressl=yes&itag=17", 
    "quality": "small", 
    "s": "0C397549D581241F0F39D3EB8BF6E9B9067F65AFD.76B46A360178C4B001E96166C46AEAE5CF0D6A35F", 
    "itag": "17", 
    "type": "video/3gpp;+codecs=\"mp4v.20.3,+mp4a.40.2\"" 
    } 
}