from __future__ import unicode_literals import os import re from .fragment import FragmentFD from ..compat import compat_urllib_error from ..utils import ( sanitize_open, encodeFilename, ) class DashSegmentsFD(FragmentFD): """ Download segments in a DASH manifest """ FD_NAME = 'dashsegments' def real_download(self, filename, info_dict): base_url = info_dict['url'] segment_urls = [info_dict['segment_urls'][0]] if self.params.get('test', False) else info_dict['segment_urls'] initialization_url = info_dict.get('initialization_url') ctx = { 'filename': filename, 'total_frags': len(segment_urls) + (1 if initialization_url else 0), } self._prepare_and_start_frag_download(ctx) def combine_url(base_url, target_url): if re.match(r'^https?://', target_url): return target_url return '%s%s%s' % (base_url, '' if base_url.endswith('/') else '/', target_url) segments_filenames = [] fragment_retries = self.params.get('fragment_retries', 0) skip_unavailable_fragments = self.params.get('skip_unavailable_fragments', True) def process_segment(segment, tmp_filename, fatal): target_url, segment_name = segment target_filename = '%s-%s' % (tmp_filename, segment_name) count = 0 while count <= fragment_retries: try: success = ctx['dl'].download(target_filename, {'url': combine_url(base_url, target_url)}) if not success: return False down, target_sanitized = sanitize_open(target_filename, 'rb') ctx['dest_stream'].write(down.read()) down.close() segments_filenames.append(target_sanitized) break except compat_urllib_error.HTTPError as err: # YouTube may often return 404 HTTP error for a fragment causing the # whole download to fail. However if the same fragment is immediately # retried with the same request data this usually succeeds (1-2 attemps # is usually enough) thus allowing to download the whole file successfully. # To be future-proof we will retry all fragments that fail with any # HTTP error. count += 1 if count <= fragment_retries: self.report_retry_fragment(err, segment_name, count, fragment_retries) if count > fragment_retries: if not fatal: self.report_skip_fragment(segment_name) return True self.report_error('giving up after %s fragment retries' % fragment_retries) return False return True segments_to_download = [(initialization_url, 'Init')] if initialization_url else [] segments_to_download.extend([ (segment_url, 'Seg%d' % i) for i, segment_url in enumerate(segment_urls)]) for i, segment in enumerate(segments_to_download): # In DASH, the first segment contains necessary headers to # generate a valid MP4 file, so always abort for the first segment fatal = i == 0 or not skip_unavailable_fragments if not process_segment(segment, ctx['tmpfilename'], fatal): return False self._finish_frag_download(ctx) for segment_file in segments_filenames: os.remove(encodeFilename(segment_file)) return True