app/common.py

   1 import os
   2 import re
   3 import json
   4 import requests
   5 import dateutil.parser
   6 from datetime import datetime, timezone
   7 from xml.etree import ElementTree
   8 from urllib.parse import parse_qs
   9 from configparser import ConfigParser
  10
  11 cf = ConfigParser()
  12 config_filename = os.environ.get('YT_CONFIG', '/etc/yt/config.ini')
  13 cf.read(config_filename)
  14
  15 def fetch_xml(feed_type, feed_id):
  16     r = requests.get(f"https://www.youtube.com/feeds/videos.xml?{feed_type}={feed_id}")
  17     if not r.ok:
  18         return None
  19
  20     return r.text
  21
  22 def parse_xml(xmldata):
  23     ns = {
  24         'atom':"http://www.w3.org/2005/Atom",
  25         'yt': "http://www.youtube.com/xml/schemas/2015",
  26         'media':"http://search.yahoo.com/mrss/"
  27     }
  28
  29     feed = ElementTree.fromstring(xmldata)
  30     author = feed.find('atom:author',ns).find('atom:name',ns).text if feed.find('atom:author',ns) else None
  31     if feed.find('yt:channelId',ns):
  32         channel_id = feed.find('yt:channelId',ns).text
  33     else: # TODO: clean this up (websub has no yt:channelId, this should be adapted for playlists)
  34         self = feed.find('atom:link[@rel="self"]',ns).get('href')
  35         channel_id = parse_qs(self.split('?')[1]).get('channel_id')[0]
  36     title = feed.find('atom:title',ns).text
  37     videos = []
  38     for entry in feed.findall('atom:entry',ns):
  39         videos.append({
  40             'video_id': entry.find('yt:videoId',ns).text,
  41             'title': entry.find('atom:title',ns).text,
  42             'published': entry.find('atom:published',ns).text,
  43             'channel_id': entry.find('yt:channelId',ns).text,
  44             'author': entry.find('atom:author',ns).find('atom:name',ns).text,
  45             # extra fields for pull_subs/webhook:
  46             'updated': entry.find('atom:updated',ns).text,
  47             #'description': entry.find('media:group',ns).find('media:description',ns).text ##xxx:missing for websub
  48         })
  49
  50     return title, author, channel_id, videos
  51
  52 def update_channel(db, xmldata):
  53     """
  54     returns True on success, False on failure. rigorous error checking is required, otherwise data will be lost!
  55     the caller MUST (as per RFC 2119) write (append) the xmlfeed into a file on error.
  56     """
  57     if not xmldata: return False
  58
  59     # Note: wbesub does not return global author
  60     title, author, channel_id, videos = parse_xml(xmldata) #xxx: perl-code had this eval'd for a die
  61
  62     c = db.cursor()
  63     for video in videos:
  64         now = datetime.now(timezone.utc)
  65         updated = dateutil.parser.parse(video['updated'])
  66         published = dateutil.parser.parse(video['updated'])
  67         # if update and published time are near-identical, it's new. use crawl time if it was published within a week.
  68         # else, it's just an update to an older video (before we subscribed, so use original upload time).
  69         if (updated - published).seconds < 60 and (now - published).days < 7:
  70             timestamp = now
  71         else:
  72             timestamp = published
  73
  74         c.execute("""
  75         INSERT OR IGNORE INTO videos (id, channel_id, title, published, crawled)
  76                        VALUES (?, ?, ?, datetime(?), datetime(?))
  77         """, (video['video_id'], video['channel_id'], video['title'], video['published'], timestamp)) #XXX:errorcheck
  78
  79     # update channel name (we don't fetch it on subscribing)
  80         author = video['author'] # XXX: doing this once per channel is enough (for pull-subs.pl)
  81         c.execute("""
  82             INSERT OR REPLACE INTO channels (id, name)
  83                             VALUES (?, ?)
  84         """, (channel_id, author)) #XXX:errorcheck
  85
  86     return True
  87
  88 def get_video_info(video_id, sts=0, algo=""):
  89     """
  90     returns the best-quality muxed video stream, the player_response, error-type/-mesage
  91     error types: 'initial':  the request to get_video_info was malformed
  92                  'player':   playabilityStatus != OK
  93                  'internal': [livestream, geolocked, exhausted]
  94     """
  95     # TODO: caching, e.g. beaker? need to not cache premiering-soon videos/livestreams/etc, though
  96     #        responses are apparently valid for 6h; maybe cache for (video_length - 2h)
  97     # TODO: errro types? ["invalid parameters", playabilitystatus, own]
  98     # todo: a bit messy; should return all unscrambled video urls in best->worst quality
  99
 100     # we try to fetch the video multiple times using different origins
 101     for el in ['embedded', 'detailpage']: # ['el-completely-absent',info,leanback,editpage,adunit,previewpage,profilepage]
 102         r = requests.get(f"https://www.youtube.com/get_video_info"+
 103             f"?video_id={video_id}"+
 104             f"&eurl=https://youtube.googleapis.com/v/{video_id}"+
 105             f"&el={el}"+
 106             f"&sts={sts}"+
 107             f"&hl=en_US") #"&hl=en&gl=US"
 108         params = parse_qs(r.text)
 109         if 'errorcode' in params: # status=fail
 110             return None, None, 'initial', f"MALFORMED: {params['reason'][0]}"
 111
 112         metadata = json.loads(params.get('player_response')[0])
 113         if metadata['playabilityStatus']['status'] != "OK":
 114             if metadata['playabilityStatus']['status'] == "UNPLAYABLE":
 115                 continue  # try again with different 'el' value. if none succeeds, we fall into "exhausted" path, which returns last tried metadata, from which the playabilityStatus.reason can be extracted. according to jwz/youtubedown, the worst error message comes from embedded, which is tried first, so it should be overwritten by a better message.
 116             return None, None, 'player', f"{metadata['playabilityStatus']['status']}: {metadata['playabilityStatus']['reason']}"
 117         if 'liveStreamability' in metadata['playabilityStatus']:
 118             return None, metadata, 'internal', "livestream" # can also check .microformat.liveBroadcastDetails.isLiveNow
 119
 120         formats = metadata['streamingData']['formats']
 121         for (i,v) in enumerate(formats):
 122             if not ('cipher' in v or 'signatureCipher' in v): continue
 123             cipher = parse_qs(v.get('cipher') or v.get('signatureCipher'))
 124             formats[i]['url'] = unscramble(cipher, algo)
 125
 126         # todo: check if we have urls or try again
 127         url = sorted(formats, key=lambda k: k['height'], reverse=True)[0]['url']
 128
 129         if 'gcr' in parse_qs(url):
 130             return None, metadata, 'internal', "geolocked"
 131
 132         return url, metadata, None, None
 133     else:
 134         return None, metadata, 'internal', "exhausted"
 135
 136 def unscramble(cipher, algo):  # test video id: UxxajLWwzqY
 137     signature = list(cipher['s'][0])
 138     for c in algo.split():
 139         op, ix = re.match(r"([rsw])(\d+)?", c).groups()
 140         if not op: continue
 141         if op == 'r': signature = list(reversed(signature))
 142         if op == 's': signature = signature[int(ix):]
 143         if op == 'w': signature[0], signature[int(ix)%len(signature)] = signature[int(ix)%len(signature)], signature[0]
 144     sp = cipher.get('sp', ['signature'])[0]
 145     sig = cipher['sig'][0] if 'sig' in cipher else ''.join(signature)
 146     return f"{cipher['url'][0]}&{sp}={sig}"
 147
 148 def prepare_metadata(metadata):
 149     meta1 = metadata['videoDetails']
 150     meta2 = metadata['microformat']['playerMicroformatRenderer']
 151     cards = metadata['cards']['cardCollectionRenderer']['cards'] if 'cards' in metadata else []
 152     endsc = metadata['endscreen']['endscreenRenderer']['elements'] if 'endscreen' in metadata else []
 153
 154     #aspect_ratio = meta2['embed']['width'] / meta2['embed']['height'], # sometimes absent
 155     aspect_ratio = meta2['thumbnail']['thumbnails'][0]['width'] / meta2['thumbnail']['thumbnails'][0]['height']
 156
 157     subtitles = sorted([
 158         {'url':cc['baseUrl'],
 159          'code':cc['languageCode'],
 160          'autogenerated':cc.get('kind')=="asr",
 161          'name':cc['name']['simpleText']}
 162         for cc in metadata['captions']['playerCaptionsTracklistRenderer']['captionTracks']
 163     ], key=lambda cc: cc['autogenerated']) if 'captionTracks' in metadata['captions']['playerCaptionsTracklistRenderer'] else []
 164
 165     def parse_infocard(card):
 166         card = card['cardRenderer']
 167         teaser = card['teaser']['simpleCardTeaserRenderer']['message']['simpleText']  # not used
 168         ctype = list(card['content'].keys())[0]
 169         content = card['content'][ctype]
 170         if ctype == "pollRenderer":
 171             ctype = "POLL"
 172             content = {
 173                 'question': content['question']['simpleText'],
 174                 'answers': [(a['text']['simpleText'],a['numVotes']) for a in content['choices']],
 175             }
 176         elif ctype == "videoInfoCardContentRenderer":
 177             ctype = "VIDEO"
 178             content = {
 179                 'video_id': content['action']['watchEndpoint']['videoId'],
 180                 'title': content['videoTitle']['simpleText'],
 181                 'author': content['channelName']['simpleText'],   # 'by xXxXx'
 182                 'length': content['lengthString']['simpleText'],  # '23:03'
 183                 'views': content['viewCountText']['simpleText'],  # '421,248 views'
 184             }
 185         elif ctype == "playlistInfoCardContentRenderer":
 186             ctype = "PLAYLIST"
 187             content = {
 188                 'playlist_id': content['action']['watchEndpoint']['playlistId'],
 189                 'video_id': content['action']['watchEndpoint']['videoId'],
 190                 'title': content['playlistTitle']['simpleText'],
 191                 'author': content['channelName']['simpleText'],
 192                 'n_videos': content['playlistVideoCount']['simpleText'],  # '21'
 193             }
 194         elif ctype == "simpleCardContentRenderer" and 'urlEndpoint' in content.get('command',{}).keys():
 195             ctype = "WEBSITE"
 196             content = {
 197                 'url': parse_qs(content['command']['urlEndpoint']['url'].split('?')[1])['q'][0],
 198                 'domain': content['displayDomain']['simpleText'],
 199                 'title': content['title']['simpleText'],
 200                 'text': content['actionButton']['simpleCardButtonRenderer']['text']['simpleText'],
 201             }
 202         else:
 203             import pprint
 204             content = {'error': f"{ctype} is not implemented; <pre>{pprint.pformat(card)}</pre>"}
 205
 206         return {'teaser': teaser, 'type': ctype, 'content': content}
 207
 208     def parse_endcard(card):
 209         card = card['endscreenElementRenderer'] if 'endscreenElementRenderer' in card.keys() else card
 210         ctype = card['style']
 211         if ctype == "CHANNEL":
 212             content = {
 213                 'channel_id': card['endpoint']['browseEndpoint']['browseId'],
 214                 'title': card['title']['simpleText'],
 215                 'icons': {e['height']: e['url'] for e in card['image']['thumbnails']},
 216             }
 217         elif ctype == "VIDEO":
 218             content = {
 219                 'video_id': card['endpoint']['watchEndpoint']['videoId'],
 220                 'title': card['title']['simpleText'],
 221                 'length': card['videoDuration']['simpleText'], # '12:21'
 222                 'views': card['metadata']['simpleText'],  # '51,649 views'
 223             }
 224         elif ctype == "PLAYLIST":
 225             content = {
 226                 'playlist_id': card['endpoint']['watchEndpoint']['playlistId'],
 227                 'video_id': card['endpoint']['watchEndpoint']['videoId'],
 228                 'title': card['title']['simpleText'],
 229                 'author': card['metadata']['simpleText'],
 230                 'n_videos': card['playlistLength']['simpleText'].replace(" videos", ""),
 231             }
 232         elif ctype == "WEBSITE":
 233             content = {
 234                 'url': parse_qs(card['endpoint']['urlEndpoint']['url'].split('?')[1])['q'][0],
 235                 'domain': card['metadata']['simpleText'],
 236                 'title': card['title']['simpleText'],
 237                 'icons': {e['height']: e['url'] for e in card['image']['thumbnails']},
 238             }
 239         else:
 240             import pprint
 241             content = {'error': f"{ctype} is not implemented; <pre>{pprint.pformat(card)}</pre>"}
 242
 243         return {'type': ctype, 'content': content}
 244
 245     return {
 246         'title': meta1['title'],
 247         'author': meta1['author'],
 248         'channel_id': meta1['channelId'],
 249         'description': meta1['shortDescription'],
 250         'published': meta2['publishDate'],
 251         'views': meta1['viewCount'],
 252         'length': int(meta1['lengthSeconds']),
 253         'rating': meta1['averageRating'],
 254         'category': meta2['category'],
 255         'aspectr': aspect_ratio,
 256         'unlisted': meta2['isUnlisted'],
 257         'countries': meta2['availableCountries'],
 258         'poster': meta2['thumbnail']['thumbnails'][0]['url'],
 259         'infocards': [parse_infocard(card) for card in cards],
 260         'endcards': [parse_endcard(card) for card in endsc],
 261         'subtitles': subtitles,
 262     }
 263
 264 def pp(*args):
 265     from pprint import pprint
 266     import sys, codecs
 267     pprint(args, stream=codecs.getwriter("utf-8")(sys.stderr.buffer))