Python爬取酷狗MP3音频的步骤

分析问题

音频url

点入某个音乐的播放界面，通过F12-Network，分析数据，可以看到有一个index.php?..返回数据中有一个play_url，打开后正是我们需要的音频。

查看该url的headers，其params参数如下，通过反复不同的几次尝试，得知r、callback、dfid、mid、platid这几项不变，而通过初步的requests尝试，发现最后一项'_'可有可无，改变的只有hash和album_id两项。

r: play/getdata
callback: jQuery1910861615852090795_1612578519454
hash: EF0DA656831F08B1FD2CB855BC38ED2C
dfid: 0Q0Clh1IcZaG3ey1J70RaTiL
mid: b6cf66837b18642cc269390b066649dc
platid: 4
album_id: 41669581
_: 1612578519455

搜索url

得知改变的只有两项后，那就容易多了，在搜索歌曲界面Network，发现song?...该url返回值中有hash和album_id存在，我们之后只用搜索结果第一项（一般要搜的歌曲排名第一）。

同样分析其params参数，改变的只有keyword、signature、clienttime、mid、uuid。后三者可以比较容易看出其为毫秒级时间戳（13位），keyword也挺容易明白，signature哪里找呢？通过全局搜索signature，发现有一个js文件中含有该关键词。

callback: callback123
keyword: 花海
page: 1
pagesize: 30
bitrate: 0
isfuzzy: 0
tag: em
inputtype: 0
platform: WebFilter
userid: -1
clientver: 2000
iscorrection: 1
privilege_filter: 0
srcappid: 2919
clienttime: 1612579100435
mid: 1612579100435
uuid: 1612579100435
dfid: -
signature: 472F60133C23184CAFC5005350C90229

JS

找到的js代码如下

"undefined" == typeof faultylabs && (faultylabs = {}),
faultylabs.MD5 = function(a) {
 function b(a) {
  var b = (a >>> 0).toString(16);
  return "00000000".substr(0, 8 - b.length) + b
 }
 function c(a) {
  for (var b = [], c = 0; c < a.length; c++)
   b = b.concat(k(a[c]));
  return b
 }
 function d(a) {
  for (var b = [], c = 0; 8 > c; c++)
   b.push(255 & a),
   a >>>= 8;
  return b
 }
 function e(a, b) {
  return a << b & 4294967295 | a >>> 32 - b
 }
 function f(a, b, c) {
  return a & b | ~a & c
 }
 function g(a, b, c) {
  return c & a | ~c & b
 }
 function h(a, b, c) {
  return a ^ b ^ c
 }
 function i(a, b, c) {
  return b ^ (a | ~c)
 }
 function j(a, b) {
  return a[b + 3] << 24 | a[b + 2] << 16 | a[b + 1] << 8 | a[b]
 }
 function k(a) {
  for (var b = [], c = 0; c < a.length; c++)
   if (a.charCodeAt(c) <= 127)
    b.push(a.charCodeAt(c));
   else
    for (var d = encodeURIComponent(a.charAt(c)).substr(1).split("%"), e = 0; e < d.length; e++)
     b.push(parseInt(d[e], 16));
  return b
 }
 function l() {
  for (var a = "", c = 0, d = 0, e = 3; e >= 0; e--)
   d = arguments[e],
   c = 255 & d,
   d >>>= 8,
   c <<= 8,
   c |= 255 & d,
   d >>>= 8,
   c <<= 8,
   c |= 255 & d,
   d >>>= 8,
   c <<= 8,
   c |= d,
   a += b(c);
  return a
 }
 function m(a) {
  for (var b = new Array(a.length), c = 0; c < a.length; c++)
   b[c] = a[c];
  return b
 }
 function n(a, b) {
  return 4294967295 & a + b
 }
 function o() {
  function a(a, b, c, d) {
   var f = v;
   v = u,
   u = t,
   t = n(t, e(n(s, n(a, n(b, c))), d)),
   s = f
  }
  var b = p.length;
  p.push(128);
  var c = p.length % 64;
  if (c > 56) {
   for (var k = 0; 64 - c > k; k++)
    p.push(0);
   c = p.length % 64
  }
  for (k = 0; 56 - c > k; k++)
   p.push(0);
  p = p.concat(d(8 * b));
  var m = 1732584193
   , o = 4023233417
   , q = 2562383102
   , r = 271733878
   , s = 0
   , t = 0
   , u = 0
   , v = 0;
  for (k = 0; k < p.length / 64; k++) {
   s = m,
   t = o,
   u = q,
   v = r;
   var w = 64 * k;
   a(f(t, u, v), 3614090360, j(p, w), 7),
   a(f(t, u, v), 3905402710, j(p, w + 4), 12),
   a(f(t, u, v), 606105819, j(p, w + 8), 17),
   a(f(t, u, v), 3250441966, j(p, w + 12), 22),
   a(f(t, u, v), 4118548399, j(p, w + 16), 7),
   a(f(t, u, v), 1200080426, j(p, w + 20), 12),
   a(f(t, u, v), 2821735955, j(p, w + 24), 17),
   a(f(t, u, v), 4249261313, j(p, w + 28), 22),
   a(f(t, u, v), 1770035416, j(p, w + 32), 7),
   a(f(t, u, v), 2336552879, j(p, w + 36), 12),
   a(f(t, u, v), 4294925233, j(p, w + 40), 17),
   a(f(t, u, v), 2304563134, j(p, w + 44), 22),
   a(f(t, u, v), 1804603682, j(p, w + 48), 7),
   a(f(t, u, v), 4254626195, j(p, w + 52), 12),
   a(f(t, u, v), 2792965006, j(p, w + 56), 17),
   a(f(t, u, v), 1236535329, j(p, w + 60), 22),
   a(g(t, u, v), 4129170786, j(p, w + 4), 5),
   a(g(t, u, v), 3225465664, j(p, w + 24), 9),
   a(g(t, u, v), 643717713, j(p, w + 44), 14),
   a(g(t, u, v), 3921069994, j(p, w), 20),
   a(g(t, u, v), 3593408605, j(p, w + 20), 5),
   a(g(t, u, v), 38016083, j(p, w + 40), 9),
   a(g(t, u, v), 3634488961, j(p, w + 60), 14),
   a(g(t, u, v), 3889429448, j(p, w + 16), 20),
   a(g(t, u, v), 568446438, j(p, w + 36), 5),
   a(g(t, u, v), 3275163606, j(p, w + 56), 9),
   a(g(t, u, v), 4107603335, j(p, w + 12), 14),
   a(g(t, u, v), 1163531501, j(p, w + 32), 20),
   a(g(t, u, v), 2850285829, j(p, w + 5cmy-a9z+l/c.amkl O