youtube-dl

Another place where youtube-dl lives on
git clone git://git.oshgnacknak.de/youtube-dl.git
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fragment.py (10957B)


      1 from __future__ import division, unicode_literals
      2 
      3 import os
      4 import time
      5 import json
      6 
      7 from .common import FileDownloader
      8 from .http import HttpFD
      9 from ..utils import (
     10     error_to_compat_str,
     11     encodeFilename,
     12     sanitize_open,
     13     sanitized_Request,
     14 )
     15 
     16 
     17 class HttpQuietDownloader(HttpFD):
     18     def to_screen(self, *args, **kargs):
     19         pass
     20 
     21 
     22 class FragmentFD(FileDownloader):
     23     """
     24     A base file downloader class for fragmented media (e.g. f4m/m3u8 manifests).
     25 
     26     Available options:
     27 
     28     fragment_retries:   Number of times to retry a fragment for HTTP error (DASH
     29                         and hlsnative only)
     30     skip_unavailable_fragments:
     31                         Skip unavailable fragments (DASH and hlsnative only)
     32     keep_fragments:     Keep downloaded fragments on disk after downloading is
     33                         finished
     34 
     35     For each incomplete fragment download youtube-dl keeps on disk a special
     36     bookkeeping file with download state and metadata (in future such files will
     37     be used for any incomplete download handled by youtube-dl). This file is
     38     used to properly handle resuming, check download file consistency and detect
     39     potential errors. The file has a .ytdl extension and represents a standard
     40     JSON file of the following format:
     41 
     42     extractor:
     43         Dictionary of extractor related data. TBD.
     44 
     45     downloader:
     46         Dictionary of downloader related data. May contain following data:
     47             current_fragment:
     48                 Dictionary with current (being downloaded) fragment data:
     49                 index:  0-based index of current fragment among all fragments
     50             fragment_count:
     51                 Total count of fragments
     52 
     53     This feature is experimental and file format may change in future.
     54     """
     55 
     56     def report_retry_fragment(self, err, frag_index, count, retries):
     57         self.to_screen(
     58             '[download] Got server HTTP error: %s. Retrying fragment %d (attempt %d of %s)...'
     59             % (error_to_compat_str(err), frag_index, count, self.format_retries(retries)))
     60 
     61     def report_skip_fragment(self, frag_index):
     62         self.to_screen('[download] Skipping fragment %d...' % frag_index)
     63 
     64     def _prepare_url(self, info_dict, url):
     65         headers = info_dict.get('http_headers')
     66         return sanitized_Request(url, None, headers) if headers else url
     67 
     68     def _prepare_and_start_frag_download(self, ctx):
     69         self._prepare_frag_download(ctx)
     70         self._start_frag_download(ctx)
     71 
     72     @staticmethod
     73     def __do_ytdl_file(ctx):
     74         return not ctx['live'] and not ctx['tmpfilename'] == '-'
     75 
     76     def _read_ytdl_file(self, ctx):
     77         assert 'ytdl_corrupt' not in ctx
     78         stream, _ = sanitize_open(self.ytdl_filename(ctx['filename']), 'r')
     79         try:
     80             ctx['fragment_index'] = json.loads(stream.read())['downloader']['current_fragment']['index']
     81         except Exception:
     82             ctx['ytdl_corrupt'] = True
     83         finally:
     84             stream.close()
     85 
     86     def _write_ytdl_file(self, ctx):
     87         frag_index_stream, _ = sanitize_open(self.ytdl_filename(ctx['filename']), 'w')
     88         downloader = {
     89             'current_fragment': {
     90                 'index': ctx['fragment_index'],
     91             },
     92         }
     93         if ctx.get('fragment_count') is not None:
     94             downloader['fragment_count'] = ctx['fragment_count']
     95         frag_index_stream.write(json.dumps({'downloader': downloader}))
     96         frag_index_stream.close()
     97 
     98     def _download_fragment(self, ctx, frag_url, info_dict, headers=None):
     99         fragment_filename = '%s-Frag%d' % (ctx['tmpfilename'], ctx['fragment_index'])
    100         fragment_info_dict = {
    101             'url': frag_url,
    102             'http_headers': headers or info_dict.get('http_headers'),
    103         }
    104         success = ctx['dl'].download(fragment_filename, fragment_info_dict)
    105         if not success:
    106             return False, None
    107         if fragment_info_dict.get('filetime'):
    108             ctx['fragment_filetime'] = fragment_info_dict.get('filetime')
    109         down, frag_sanitized = sanitize_open(fragment_filename, 'rb')
    110         ctx['fragment_filename_sanitized'] = frag_sanitized
    111         frag_content = down.read()
    112         down.close()
    113         return True, frag_content
    114 
    115     def _append_fragment(self, ctx, frag_content):
    116         try:
    117             ctx['dest_stream'].write(frag_content)
    118             ctx['dest_stream'].flush()
    119         finally:
    120             if self.__do_ytdl_file(ctx):
    121                 self._write_ytdl_file(ctx)
    122             if not self.params.get('keep_fragments', False):
    123                 os.remove(encodeFilename(ctx['fragment_filename_sanitized']))
    124             del ctx['fragment_filename_sanitized']
    125 
    126     def _prepare_frag_download(self, ctx):
    127         if 'live' not in ctx:
    128             ctx['live'] = False
    129         if not ctx['live']:
    130             total_frags_str = '%d' % ctx['total_frags']
    131             ad_frags = ctx.get('ad_frags', 0)
    132             if ad_frags:
    133                 total_frags_str += ' (not including %d ad)' % ad_frags
    134         else:
    135             total_frags_str = 'unknown (live)'
    136         self.to_screen(
    137             '[%s] Total fragments: %s' % (self.FD_NAME, total_frags_str))
    138         self.report_destination(ctx['filename'])
    139         dl = HttpQuietDownloader(
    140             self.ydl,
    141             {
    142                 'continuedl': True,
    143                 'quiet': True,
    144                 'noprogress': True,
    145                 'ratelimit': self.params.get('ratelimit'),
    146                 'retries': self.params.get('retries', 0),
    147                 'nopart': self.params.get('nopart', False),
    148                 'test': self.params.get('test', False),
    149             }
    150         )
    151         tmpfilename = self.temp_name(ctx['filename'])
    152         open_mode = 'wb'
    153         resume_len = 0
    154 
    155         # Establish possible resume length
    156         if os.path.isfile(encodeFilename(tmpfilename)):
    157             open_mode = 'ab'
    158             resume_len = os.path.getsize(encodeFilename(tmpfilename))
    159 
    160         # Should be initialized before ytdl file check
    161         ctx.update({
    162             'tmpfilename': tmpfilename,
    163             'fragment_index': 0,
    164         })
    165 
    166         if self.__do_ytdl_file(ctx):
    167             if os.path.isfile(encodeFilename(self.ytdl_filename(ctx['filename']))):
    168                 self._read_ytdl_file(ctx)
    169                 is_corrupt = ctx.get('ytdl_corrupt') is True
    170                 is_inconsistent = ctx['fragment_index'] > 0 and resume_len == 0
    171                 if is_corrupt or is_inconsistent:
    172                     message = (
    173                         '.ytdl file is corrupt' if is_corrupt else
    174                         'Inconsistent state of incomplete fragment download')
    175                     self.report_warning(
    176                         '%s. Restarting from the beginning...' % message)
    177                     ctx['fragment_index'] = resume_len = 0
    178                     if 'ytdl_corrupt' in ctx:
    179                         del ctx['ytdl_corrupt']
    180                     self._write_ytdl_file(ctx)
    181             else:
    182                 self._write_ytdl_file(ctx)
    183                 assert ctx['fragment_index'] == 0
    184 
    185         dest_stream, tmpfilename = sanitize_open(tmpfilename, open_mode)
    186 
    187         ctx.update({
    188             'dl': dl,
    189             'dest_stream': dest_stream,
    190             'tmpfilename': tmpfilename,
    191             # Total complete fragments downloaded so far in bytes
    192             'complete_frags_downloaded_bytes': resume_len,
    193         })
    194 
    195     def _start_frag_download(self, ctx):
    196         resume_len = ctx['complete_frags_downloaded_bytes']
    197         total_frags = ctx['total_frags']
    198         # This dict stores the download progress, it's updated by the progress
    199         # hook
    200         state = {
    201             'status': 'downloading',
    202             'downloaded_bytes': resume_len,
    203             'fragment_index': ctx['fragment_index'],
    204             'fragment_count': total_frags,
    205             'filename': ctx['filename'],
    206             'tmpfilename': ctx['tmpfilename'],
    207         }
    208 
    209         start = time.time()
    210         ctx.update({
    211             'started': start,
    212             # Amount of fragment's bytes downloaded by the time of the previous
    213             # frag progress hook invocation
    214             'prev_frag_downloaded_bytes': 0,
    215         })
    216 
    217         def frag_progress_hook(s):
    218             if s['status'] not in ('downloading', 'finished'):
    219                 return
    220 
    221             time_now = time.time()
    222             state['elapsed'] = time_now - start
    223             frag_total_bytes = s.get('total_bytes') or 0
    224             if not ctx['live']:
    225                 estimated_size = (
    226                     (ctx['complete_frags_downloaded_bytes'] + frag_total_bytes)
    227                     / (state['fragment_index'] + 1) * total_frags)
    228                 state['total_bytes_estimate'] = estimated_size
    229 
    230             if s['status'] == 'finished':
    231                 state['fragment_index'] += 1
    232                 ctx['fragment_index'] = state['fragment_index']
    233                 state['downloaded_bytes'] += frag_total_bytes - ctx['prev_frag_downloaded_bytes']
    234                 ctx['complete_frags_downloaded_bytes'] = state['downloaded_bytes']
    235                 ctx['prev_frag_downloaded_bytes'] = 0
    236             else:
    237                 frag_downloaded_bytes = s['downloaded_bytes']
    238                 state['downloaded_bytes'] += frag_downloaded_bytes - ctx['prev_frag_downloaded_bytes']
    239                 if not ctx['live']:
    240                     state['eta'] = self.calc_eta(
    241                         start, time_now, estimated_size - resume_len,
    242                         state['downloaded_bytes'] - resume_len)
    243                 state['speed'] = s.get('speed') or ctx.get('speed')
    244                 ctx['speed'] = state['speed']
    245                 ctx['prev_frag_downloaded_bytes'] = frag_downloaded_bytes
    246             self._hook_progress(state)
    247 
    248         ctx['dl'].add_progress_hook(frag_progress_hook)
    249 
    250         return start
    251 
    252     def _finish_frag_download(self, ctx):
    253         ctx['dest_stream'].close()
    254         if self.__do_ytdl_file(ctx):
    255             ytdl_filename = encodeFilename(self.ytdl_filename(ctx['filename']))
    256             if os.path.isfile(ytdl_filename):
    257                 os.remove(ytdl_filename)
    258         elapsed = time.time() - ctx['started']
    259 
    260         if ctx['tmpfilename'] == '-':
    261             downloaded_bytes = ctx['complete_frags_downloaded_bytes']
    262         else:
    263             self.try_rename(ctx['tmpfilename'], ctx['filename'])
    264             if self.params.get('updatetime', True):
    265                 filetime = ctx.get('fragment_filetime')
    266                 if filetime:
    267                     try:
    268                         os.utime(ctx['filename'], (time.time(), filetime))
    269                     except Exception:
    270                         pass
    271             downloaded_bytes = os.path.getsize(encodeFilename(ctx['filename']))
    272 
    273         self._hook_progress({
    274             'downloaded_bytes': downloaded_bytes,
    275             'total_bytes': downloaded_bytes,
    276             'filename': ctx['filename'],
    277             'status': 'finished',
    278             'elapsed': elapsed,
    279         })