from __future__ import division, unicode_literals import re import json from .fragment import FragmentFD from ..compat import compat_urllib_error from ..utils import try_get from ..extractor.youtube import YoutubeBaseInfoExtractor as YT_BaseIE class YoutubeLiveChatReplayFD(FragmentFD): """ Downloads YouTube live chat replays fragment by fragment """ FD_NAME = 'youtube_live_chat_replay' def real_download(self, filename, info_dict): video_id = info_dict['video_id'] self.to_screen('[%s] Downloading live chat' % self.FD_NAME) fragment_retries = self.params.get('fragment_retries', 0) test = self.params.get('test', False) ctx = { 'filename': filename, 'live': True, 'total_frags': None, } def dl_fragment(url): headers = info_dict.get('http_headers', {}) return self._download_fragment(ctx, url, info_dict, headers) def parse_yt_initial_data(data): patterns = ( r'%s\\s*%s' % (YT_BaseIE._YT_INITIAL_DATA_RE, YT_BaseIE._YT_INITIAL_BOUNDARY_RE), r'%s' % YT_BaseIE._YT_INITIAL_DATA_RE) data = data.decode('utf-8', 'replace') for patt in patterns: try: raw_json = re.search(patt, data).group(1) return json.loads(raw_json) except AttributeError: continue def download_and_parse_fragment(url, frag_index): count = 0 while count <= fragment_retries: try: success, raw_fragment = dl_fragment(url) if not success: return False, None, None data = parse_yt_initial_data(raw_fragment) or json.loads(raw_fragment)['response'] live_chat_continuation = try_get( data, lambda x: x['continuationContents']['liveChatContinuation'], dict) or {} offset = continuation_id = None processed_fragment = bytearray() for action in live_chat_continuation.get('actions', []): if 'replayChatItemAction' in action: replay_chat_item_action = action['replayChatItemAction'] offset = int(replay_chat_item_action['videoOffsetTimeMsec']) processed_fragment.extend( json.dumps(action, ensure_ascii=False).encode('utf-8') + b'\n') if offset is not None: continuation_id = try_get( live_chat_continuation, lambda x: x['continuations'][0]['liveChatReplayContinuationData']['continuation']) self._append_fragment(ctx, processed_fragment) return True, continuation_id, offset except compat_urllib_error.HTTPError as err: count += 1 if count <= fragment_retries: self.report_retry_fragment(err, frag_index, count, fragment_retries) if count > fragment_retries: self.report_error('giving up after %s fragment retries' % fragment_retries) return False, None, None self._prepare_and_start_frag_download(ctx) success, raw_fragment = dl_fragment( 'https://www.youtube.com/watch?v={}'.format(video_id)) if not success: return False data = parse_yt_initial_data(raw_fragment) continuation_id = try_get( data, lambda x: x['contents']['twoColumnWatchNextResults']['conversationBar']['liveChatRenderer']['continuations'][0]['reloadContinuationData']['continuation']) # no data yet but required to call _append_fragment self._append_fragment(ctx, b'') frag_index = offset = 0 while continuation_id is not None: frag_index += 1 url = 'https://www.youtube.com/live_chat_replay?continuation=%s' % continuation_id if frag_index > 1: url += '&playerOffsetMs=%d&hidden=false&pbj=1' % max(offset - 5000, 0) success, continuation_id, offset = download_and_parse_fragment(url, frag_index) if not success: return False if test: break self._finish_frag_download(ctx) return True