youtube_dl/extractor/subtitles.py

   1 import socket
   2
   3 from .common import InfoExtractor
   4
   5 from ..utils import (
   6     compat_http_client,
   7     compat_urllib_error,
   8     compat_urllib_request,
   9     compat_str,
  10 )
  11
  12
  13 class SubtitlesIE(InfoExtractor):
  14
  15     def report_video_subtitles_available(self, video_id, sub_lang_list):
  16         """Report available subtitles."""
  17         sub_lang = ",".join(list(sub_lang_list.keys()))
  18         self.to_screen(u'%s: Available subtitles for video: %s' %
  19                        (video_id, sub_lang))
  20
  21     def _list_available_subtitles(self, video_id):
  22         sub_lang_list = self._get_available_subtitles(video_id)
  23         self.report_video_subtitles_available(video_id, sub_lang_list)
  24
  25     def _extract_subtitles(self, video_id):
  26         """
  27         Return a dictionary: {language: subtitles} or {} if the subtitles
  28         couldn't be found
  29         """
  30         sub_lang_list = self._get_available_subtitles(video_id)
  31         if not sub_lang_list:  # error, it didn't get the available subtitles
  32             return {}
  33
  34         if self._downloader.params.get('writesubtitles', False):
  35             if self._downloader.params.get('subtitleslang', False):
  36                 sub_lang = self._downloader.params.get('subtitleslang')
  37             elif 'en' in sub_lang_list:
  38                 sub_lang = 'en'
  39             else:
  40                 sub_lang = list(sub_lang_list.keys())[0]
  41             if not sub_lang in sub_lang_list:
  42                 self._downloader.report_warning(u'no closed captions found in the specified language "%s"' % sub_lang)
  43                 return {}
  44             sub_lang_list = {sub_lang: sub_lang_list[sub_lang]}
  45
  46         subtitles = {}
  47         for sub_lang, url in sub_lang_list.iteritems():
  48             subtitle = self._request_subtitle_url(sub_lang, url)
  49             if subtitle:
  50                 subtitles[sub_lang] = subtitle
  51         return subtitles
  52
  53     def _request_subtitle_url(self, sub_lang, url):
  54         try:
  55             sub = compat_urllib_request.urlopen(url).read().decode('utf-8')
  56         except (compat_urllib_error.URLError, compat_http_client.HTTPException, socket.error) as err:
  57             self._downloader.report_warning(u'unable to download video subtitles for %s: %s' % (sub_lang, compat_str(err)))
  58             return
  59         if not sub:
  60             self._downloader.report_warning(u'Did not fetch video subtitles')
  61             return
  62         return sub
  63
  64     def _get_available_subtitles(self, video_id):
  65         """returns the list of available subtitles like this {lang: url} """
  66         """or {} if not available. Must be redefined by the subclasses."""
  67         pass
  68
  69     def _request_automatic_caption(self, video_id, webpage):
  70         """Request automatic caption. Redefine in subclasses."""
  71         """returns a tuple of ... """
  72         # return [(err_msg, None, None)]
  73         pass