Fix KeyError when missing attributes in MPD

[oleksis]

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Make sure you are using the latest version: run youtube-dl --version and ensure your version is 2019.04.01. If it's not, read this FAQ entry and update. Issues with outdated version will be rejected.

• [x ] I've verified and I assure that I'm running youtube-dl 2019.04.01

Before submitting an issue make sure you have:

• At least skimmed through the README, most notably the FAQ and BUGS sections
• [x ] Searched the bugtracker for similar issues including closed ones
• [x ] Checked that provided video/audio/playlist URLs (if any) are alive and playable in a browser

What is the purpose of your issue?

• [x ] Bug report (encountered problems with youtube-dl)
• Site support request (request for adding support for a new site)
• Feature request (request for a new functionality)
• Question
• Other

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The following sections concretize particular purposed issues, you can erase any section (the contents between triple ---) not applicable to your issue

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If the purpose of this issue is a bug report, site support request or you are not completely sure provide the full verbose output as follows:

Add the -v flag to your command line you run youtube-dl with (youtube-dl -v <your command line>), copy the whole output and insert it here. It should look similar to one below (replace it with your log inserted between triple ```):

"C:\Program Files\Python36\python.exe" D:/PYTHON/youtube-dl/bin/youtube-dl -v --no-check-certificate https://www.picta.cu/medias/inocencia-2019-2019-04-01-17-11-21-603318
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: ['-v', '--no-check-certificate', 'https://www.picta.cu/medias/inocencia-2019-2019-04-01-17-11-21-603318']
[debug] Encodings: locale cp1252, fs utf-8, out UTF-8, pref cp1252
[debug] youtube-dl version 2019.04.01
[debug] Git HEAD: 9bcbbd811
[debug] Python version 3.6.7 (CPython) - Windows-7-6.1.7601-SP1
[debug] exe versions: ffmpeg N-93056-g1e03d60054, ffprobe N-93056-g1e03d60054
[debug] Proxy map: {}
[picta] inocencia-2019-2019-04-01-17-11-21-603318: Downloading video JSON
[picta] inocencia-2019-2019-04-01-17-11-21-603318: Downloading MPD manifest
WARNING: Unknown codec vp09.00.11.08
ERROR: An extractor error has occurred. (caused by KeyError('sourceURL',)); 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 "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 508, in extract
    ie_result = self._real_extract(url)
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\picta.py", line 93, in _real_extract
    formats.extend(self._extract_mpd_formats(info.get('manifest_url'), video_id, formats_dict=self._formats))
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 2002, in _extract_mpd_formats
    formats_dict=formats_dict, mpd_url=mpd_url)
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 2137, in _parse_mpd_formats
    representation_ms_info = extract_multisegment_info(representation, adaption_set_ms_info)
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 2063, in extract_multisegment_info
    extract_Initialization(segment_list)
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 2058, in extract_Initialization
    ms_info['initialization_url'] = initialization.attrib['sourceURL']
KeyError: 'sourceURL'
Traceback (most recent call last):
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 508, in extract
    ie_result = self._real_extract(url)
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\picta.py", line 93, in _real_extract
    formats.extend(self._extract_mpd_formats(info.get('manifest_url'), video_id, formats_dict=self._formats))
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 2002, in _extract_mpd_formats
    formats_dict=formats_dict, mpd_url=mpd_url)
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 2137, in _parse_mpd_formats
    representation_ms_info = extract_multisegment_info(representation, adaption_set_ms_info)
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 2063, in extract_multisegment_info
    extract_Initialization(segment_list)
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 2058, in extract_Initialization
    ms_info['initialization_url'] = initialization.attrib['sourceURL']
KeyError: 'sourceURL'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "D:\PYTHON\youtube-dl\youtube_dl\YoutubeDL.py", line 796, in extract_info
    ie_result = ie.extract(url)
  File "D:\PYTHON\youtube-dl\youtube_dl\extractor\common.py", line 521, in extract
    raise ExtractorError('An extractor error has occurred.', cause=e)
youtube_dl.utils.ExtractorError: An extractor error has occurred. (caused by KeyError('sourceURL',)); 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.

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If the purpose of this issue is a site support request please provide all kinds of example URLs support for which should be included (replace following example URLs by yours):

• Single video: https://www.picta.cu/medias/inocencia-2019-2019-04-01-17-11-21-603318

Note that youtube-dl does not support sites dedicated to copyright infringement. In order for site support request to be accepted all provided example URLs should not violate any copyrights.

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Description of your issue, suggested solution and other information

Fix KeyError when missing attributes in MPD
Get element attribute using element.get('key') instead of element.attrib['index'] manifests like:

SegmentList/Initialization@sourceURL
SegmentList/SegmentURL@media

Example MPD manifest https://www.picta.cu/videos/3bf20311b6564d61a0fd519b3c7dcced/manifest.mpd

Related issue #18875
@dstftw @roorolj98y

Pull Commit [picta] Fix KeyError when missing attributes in MPD #0fc37c4