[SkylineWebcamsIE] Attempt to fix extractor, should investigate further

[Microeinstein]

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• Bug fix
• Improvement
• New extractor
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Description of your pull request and other information

SkylineWebcams support is broken — I got the following output trying a random webcam:

$ youtube-dl -vU 'https://www.skylinewebcams.com/it/webcam/espana/canarias/santa-cruz-de-tenerife/playa-los-cristianos.html'
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: ['-vU', 'https://www.skylinewebcams.com/it/webcam/espana/canarias/santa-cruz-de-tenerife/playa-los-cristianos.html']
[debug] Encodings: locale UTF-8, fs utf-8, out utf-8, pref UTF-8
[debug] youtube-dl version 2021.12.17
[debug] Python version 3.11.3 (CPython) - Linux-6.2.10-1-clear-x86_64-with-glibc2.37
[debug] exe versions: ffmpeg 6.0, ffprobe 6.0
[debug] Proxy map: {}
It looks like you installed youtube-dl with a package manager, pip, setup.py or a tarball. Please use that to update.
[SkylineWebcams] playa-los-cristianos: Downloading webpage
ERROR: Unable to extract stream url; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
Traceback (most recent call last):
  File "/usr/lib/python3.11/site-packages/youtube_dl/YoutubeDL.py", line 815, in wrapper
    return func(self, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/youtube_dl/YoutubeDL.py", line 836, in __extract_info
    ie_result = ie.extract(url)
                ^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/youtube_dl/extractor/common.py", line 534, in extract
    ie_result = self._real_extract(url)
                ^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/youtube_dl/extractor/skylinewebcams.py", line 28, in _real_extract
    stream_url = self._search_regex(
                 ^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/youtube_dl/extractor/common.py", line 1012, in _search_regex
    raise RegexNotFoundError('Unable to extract %s' % _name)
youtube_dl.utils.RegexNotFoundError: Unable to extract stream url; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.

The raw stream url is now source:'livee.m3u8?a=abcd1234...' — I tried to fix the regex, then noticed the base domain did not appear in the stream url and fixed that too, but it doesn't suffice. Inspecting network requests there's no livee.m3u8 but various ones to https://hd-auth.skylinewebcams.com/live, so also tried to do a simple replace and it seems working now.

Needless to say it's a pretty hackish approach and it should be investigated further.

[dirkf]

You're on to something here. The player JS loaded by the page has this fragment:

_.prototype._normalizeSources = function (e) {
  var t = e.sources || (void 0 !== e.source ? [
    'https://hd-auth.skylinewebcams.com/' + e.source.replace('livee.', 'live.')
  ] : [
  ]);

[Microeinstein]

Oh! That's nice 😄 Should I/we reflect the same exact logic into youtube-dl?