youtube_dl/downloader/fragment.py

   1 from __future__ import division, unicode_literals
   2
   3 import os
   4 import time
   5
   6 from .common import FileDownloader
   7 from .http import HttpFD
   8 from ..utils import (
   9     encodeFilename,
  10     sanitize_open,
  11 )
  12
  13
  14 class HttpQuietDownloader(HttpFD):
  15     def to_screen(self, *args, **kargs):
  16         pass
  17
  18
  19 class FragmentFD(FileDownloader):
  20     """
  21     A base file downloader class for fragmented media (e.g. f4m/m3u8 manifests).
  22
  23     Available options:
  24
  25     fragment_retries:   Number of times to retry a fragment for HTTP error (DASH
  26                         and hlsnative only)
  27     skip_unavailable_fragments:
  28                         Skip unavailable fragments (DASH and hlsnative only)
  29     """
  30
  31     def report_retry_fragment(self, fragment_name, count, retries):
  32         self.to_screen(
  33             '[download] Got server HTTP error: %s. Retrying fragment %s (attempt %d of %s)...'
  34             % (fragment_name, count, self.format_retries(retries)))
  35
  36     def report_skip_fragment(self, fragment_name):
  37         self.to_screen('[download] Skipping fragment %s...' % fragment_name)
  38
  39     def _prepare_and_start_frag_download(self, ctx):
  40         self._prepare_frag_download(ctx)
  41         self._start_frag_download(ctx)
  42
  43     def _prepare_frag_download(self, ctx):
  44         if 'live' not in ctx:
  45             ctx['live'] = False
  46         self.to_screen(
  47             '[%s] Total fragments: %s'
  48             % (self.FD_NAME, ctx['total_frags'] if not ctx['live'] else 'unknown (live)'))
  49         self.report_destination(ctx['filename'])
  50         dl = HttpQuietDownloader(
  51             self.ydl,
  52             {
  53                 'continuedl': True,
  54                 'quiet': True,
  55                 'noprogress': True,
  56                 'ratelimit': self.params.get('ratelimit'),
  57                 'retries': self.params.get('retries', 0),
  58                 'test': self.params.get('test', False),
  59             }
  60         )
  61         tmpfilename = self.temp_name(ctx['filename'])
  62         dest_stream, tmpfilename = sanitize_open(tmpfilename, 'wb')
  63         ctx.update({
  64             'dl': dl,
  65             'dest_stream': dest_stream,
  66             'tmpfilename': tmpfilename,
  67         })
  68
  69     def _start_frag_download(self, ctx):
  70         total_frags = ctx['total_frags']
  71         # This dict stores the download progress, it's updated by the progress
  72         # hook
  73         state = {
  74             'status': 'downloading',
  75             'downloaded_bytes': 0,
  76             'frag_index': 0,
  77             'frag_count': total_frags,
  78             'filename': ctx['filename'],
  79             'tmpfilename': ctx['tmpfilename'],
  80         }
  81
  82         start = time.time()
  83         ctx.update({
  84             'started': start,
  85             # Total complete fragments downloaded so far in bytes
  86             'complete_frags_downloaded_bytes': 0,
  87             # Amount of fragment's bytes downloaded by the time of the previous
  88             # frag progress hook invocation
  89             'prev_frag_downloaded_bytes': 0,
  90         })
  91
  92         def frag_progress_hook(s):
  93             if s['status'] not in ('downloading', 'finished'):
  94                 return
  95
  96             time_now = time.time()
  97             state['elapsed'] = time_now - start
  98             frag_total_bytes = s.get('total_bytes') or 0
  99             if not ctx['live']:
 100                 estimated_size = (
 101                     (ctx['complete_frags_downloaded_bytes'] + frag_total_bytes) /
 102                     (state['frag_index'] + 1) * total_frags)
 103                 state['total_bytes_estimate'] = estimated_size
 104
 105             if s['status'] == 'finished':
 106                 state['frag_index'] += 1
 107                 state['downloaded_bytes'] += frag_total_bytes - ctx['prev_frag_downloaded_bytes']
 108                 ctx['complete_frags_downloaded_bytes'] = state['downloaded_bytes']
 109                 ctx['prev_frag_downloaded_bytes'] = 0
 110             else:
 111                 frag_downloaded_bytes = s['downloaded_bytes']
 112                 state['downloaded_bytes'] += frag_downloaded_bytes - ctx['prev_frag_downloaded_bytes']
 113                 if not ctx['live']:
 114                     state['eta'] = self.calc_eta(
 115                         start, time_now, estimated_size,
 116                         state['downloaded_bytes'])
 117                 state['speed'] = s.get('speed') or ctx.get('speed')
 118                 ctx['speed'] = state['speed']
 119                 ctx['prev_frag_downloaded_bytes'] = frag_downloaded_bytes
 120             self._hook_progress(state)
 121
 122         ctx['dl'].add_progress_hook(frag_progress_hook)
 123
 124         return start
 125
 126     def _finish_frag_download(self, ctx):
 127         ctx['dest_stream'].close()
 128         elapsed = time.time() - ctx['started']
 129         self.try_rename(ctx['tmpfilename'], ctx['filename'])
 130         fsize = os.path.getsize(encodeFilename(ctx['filename']))
 131
 132         self._hook_progress({
 133             'downloaded_bytes': fsize,
 134             'total_bytes': fsize,
 135             'filename': ctx['filename'],
 136             'status': 'finished',
 137             'elapsed': elapsed,
 138         })