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
  24     def report_retry_fragment(self, fragment_name, count, retries):
  25         self.to_screen(
  26             '[download] Got server HTTP error. Retrying fragment %s (attempt %d of %s)...'
  27             % (fragment_name, count, self.format_retries(retries)))
  28
  29     def _prepare_and_start_frag_download(self, ctx):
  30         self._prepare_frag_download(ctx)
  31         self._start_frag_download(ctx)
  32
  33     def _prepare_frag_download(self, ctx):
  34         if 'live' not in ctx:
  35             ctx['live'] = False
  36         self.to_screen(
  37             '[%s] Total fragments: %s'
  38             % (self.FD_NAME, ctx['total_frags'] if not ctx['live'] else 'unknown (live)'))
  39         self.report_destination(ctx['filename'])
  40         dl = HttpQuietDownloader(
  41             self.ydl,
  42             {
  43                 'continuedl': True,
  44                 'quiet': True,
  45                 'noprogress': True,
  46                 'ratelimit': self.params.get('ratelimit'),
  47                 'retries': self.params.get('retries', 0),
  48                 'test': self.params.get('test', False),
  49             }
  50         )
  51         tmpfilename = self.temp_name(ctx['filename'])
  52         dest_stream, tmpfilename = sanitize_open(tmpfilename, 'wb')
  53         ctx.update({
  54             'dl': dl,
  55             'dest_stream': dest_stream,
  56             'tmpfilename': tmpfilename,
  57         })
  58
  59     def _start_frag_download(self, ctx):
  60         total_frags = ctx['total_frags']
  61         # This dict stores the download progress, it's updated by the progress
  62         # hook
  63         state = {
  64             'status': 'downloading',
  65             'downloaded_bytes': 0,
  66             'frag_index': 0,
  67             'frag_count': total_frags,
  68             'filename': ctx['filename'],
  69             'tmpfilename': ctx['tmpfilename'],
  70         }
  71
  72         start = time.time()
  73         ctx.update({
  74             'started': start,
  75             # Total complete fragments downloaded so far in bytes
  76             'complete_frags_downloaded_bytes': 0,
  77             # Amount of fragment's bytes downloaded by the time of the previous
  78             # frag progress hook invocation
  79             'prev_frag_downloaded_bytes': 0,
  80         })
  81
  82         def frag_progress_hook(s):
  83             if s['status'] not in ('downloading', 'finished'):
  84                 return
  85
  86             time_now = time.time()
  87             state['elapsed'] = time_now - start
  88             frag_total_bytes = s.get('total_bytes') or 0
  89             if not ctx['live']:
  90                 estimated_size = (
  91                     (ctx['complete_frags_downloaded_bytes'] + frag_total_bytes) /
  92                     (state['frag_index'] + 1) * total_frags)
  93                 state['total_bytes_estimate'] = estimated_size
  94
  95             if s['status'] == 'finished':
  96                 state['frag_index'] += 1
  97                 state['downloaded_bytes'] += frag_total_bytes - ctx['prev_frag_downloaded_bytes']
  98                 ctx['complete_frags_downloaded_bytes'] = state['downloaded_bytes']
  99                 ctx['prev_frag_downloaded_bytes'] = 0
 100             else:
 101                 frag_downloaded_bytes = s['downloaded_bytes']
 102                 state['downloaded_bytes'] += frag_downloaded_bytes - ctx['prev_frag_downloaded_bytes']
 103                 if not ctx['live']:
 104                     state['eta'] = self.calc_eta(
 105                         start, time_now, estimated_size,
 106                         state['downloaded_bytes'])
 107                 state['speed'] = s.get('speed') or ctx.get('speed')
 108                 ctx['speed'] = state['speed']
 109                 ctx['prev_frag_downloaded_bytes'] = frag_downloaded_bytes
 110             self._hook_progress(state)
 111
 112         ctx['dl'].add_progress_hook(frag_progress_hook)
 113
 114         return start
 115
 116     def _finish_frag_download(self, ctx):
 117         ctx['dest_stream'].close()
 118         elapsed = time.time() - ctx['started']
 119         self.try_rename(ctx['tmpfilename'], ctx['filename'])
 120         fsize = os.path.getsize(encodeFilename(ctx['filename']))
 121
 122         self._hook_progress({
 123             'downloaded_bytes': fsize,
 124             'total_bytes': fsize,
 125             'filename': ctx['filename'],
 126             'status': 'finished',
 127             'elapsed': elapsed,
 128         })