from __future__ import division, unicode_literals import os import time import json try: from Crypto.Cipher import AES can_decrypt_frag = True except ImportError: can_decrypt_frag = False try: import concurrent.futures can_threaded_download = True except ImportError: can_threaded_download = False from .common import FileDownloader from .http import HttpFD from ..compat import ( compat_urllib_error, compat_struct_pack, ) from ..utils import ( DownloadError, error_to_compat_str, encodeFilename, sanitize_open, sanitized_Request, ) class HttpQuietDownloader(HttpFD): def to_screen(self, *args, **kargs): pass class FragmentFD(FileDownloader): """ A base file downloader class for fragmented media (e.g. f4m/m3u8 manifests). Available options: fragment_retries: Number of times to retry a fragment for HTTP error (DASH and hlsnative only) skip_unavailable_fragments: Skip unavailable fragments (DASH and hlsnative only) keep_fragments: Keep downloaded fragments on disk after downloading is finished _no_ytdl_file: Don't use .ytdl file For each incomplete fragment download yt-dlp keeps on disk a special bookkeeping file with download state and metadata (in future such files will be used for any incomplete download handled by yt-dlp). This file is used to properly handle resuming, check download file consistency and detect potential errors. The file has a .ytdl extension and represents a standard JSON file of the following format: extractor: Dictionary of extractor related data. TBD. downloader: Dictionary of downloader related data. May contain following data: current_fragment: Dictionary with current (being downloaded) fragment data: index: 0-based index of current fragment among all fragments fragment_count: Total count of fragments This feature is experimental and file format may change in future. """ def report_retry_fragment(self, err, frag_index, count, retries): self.to_screen( '\r[download] Got server HTTP error: %s. Retrying fragment %d (attempt %d of %s) ...' % (error_to_compat_str(err), frag_index, count, self.format_retries(retries))) def report_skip_fragment(self, frag_index): self.to_screen('[download] Skipping fragment %d ...' % frag_index) def _prepare_url(self, info_dict, url): headers = info_dict.get('http_headers') return sanitized_Request(url, None, headers) if headers else url def _prepare_and_start_frag_download(self, ctx, info_dict): self._prepare_frag_download(ctx) self._start_frag_download(ctx, info_dict) def __do_ytdl_file(self, ctx): return not ctx['live'] and not ctx['tmpfilename'] == '-' and not self.params.get('_no_ytdl_file') def _read_ytdl_file(self, ctx): assert 'ytdl_corrupt' not in ctx stream, _ = sanitize_open(self.ytdl_filename(ctx['filename']), 'r') try: ytdl_data = json.loads(stream.read()) ctx['fragment_index'] = ytdl_data['downloader']['current_fragment']['index'] if 'extra_state' in ytdl_data['downloader']: ctx['extra_state'] = ytdl_data['downloader']['extra_state'] except Exception: ctx['ytdl_corrupt'] = True finally: stream.close() def _write_ytdl_file(self, ctx): frag_index_stream, _ = sanitize_open(self.ytdl_filename(ctx['filename']), 'w') try: downloader = { 'current_fragment': { 'index': ctx['fragment_index'], }, } if 'extra_state' in ctx: downloader['extra_state'] = ctx['extra_state'] if ctx.get('fragment_count') is not None: downloader['fragment_count'] = ctx['fragment_count'] frag_index_stream.write(json.dumps({'downloader': downloader})) finally: frag_index_stream.close() def _download_fragment(self, ctx, frag_url, info_dict, headers=None, request_data=None): fragment_filename = '%s-Frag%d' % (ctx['tmpfilename'], ctx['fragment_index']) fragment_info_dict = { 'url': frag_url, 'http_headers': headers or info_dict.get('http_headers'), 'request_data': request_data, } success = ctx['dl'].download(fragment_filename, fragment_info_dict) if not success: return False, None if fragment_info_dict.get('filetime'): ctx['fragment_filetime'] = fragment_info_dict.get('filetime') ctx['fragment_filename_sanitized'] = fragment_filename return True, self._read_fragment(ctx) def _read_fragment(self, ctx): down, frag_sanitized = sanitize_open(ctx['fragment_filename_sanitized'], 'rb') ctx['fragment_filename_sanitized'] = frag_sanitized frag_content = down.read() down.close() return frag_content def _append_fragment(self, ctx, frag_content): try: ctx['dest_stream'].write(frag_content) ctx['dest_stream'].flush() finally: if self.__do_ytdl_file(ctx): self._write_ytdl_file(ctx) if not self.params.get('keep_fragments', False): os.remove(encodeFilename(ctx['fragment_filename_sanitized'])) del ctx['fragment_filename_sanitized'] def _prepare_frag_download(self, ctx): if 'live' not in ctx: ctx['live'] = False if not ctx['live']: total_frags_str = '%d' % ctx['total_frags'] ad_frags = ctx.get('ad_frags', 0) if ad_frags: total_frags_str += ' (not including %d ad)' % ad_frags else: total_frags_str = 'unknown (live)' self.to_screen( '[%s] Total fragments: %s' % (self.FD_NAME, total_frags_str)) self.report_destination(ctx['filename']) dl = HttpQuietDownloader( self.ydl, { 'continuedl': True, 'quiet': True, 'noprogress': True, 'ratelimit': self.params.get('ratelimit'), 'retries': self.params.get('retries', 0), 'nopart': self.params.get('nopart', False), 'test': self.params.get('test', False), } ) tmpfilename = self.temp_name(ctx['filename']) open_mode = 'wb' resume_len = 0 # Establish possible resume length if os.path.isfile(encodeFilename(tmpfilename)): open_mode = 'ab' resume_len = os.path.getsize(encodeFilename(tmpfilename)) # Should be initialized before ytdl file check ctx.update({ 'tmpfilename': tmpfilename, 'fragment_index': 0, }) if self.__do_ytdl_file(ctx): if os.path.isfile(encodeFilename(self.ytdl_filename(ctx['filename']))): self._read_ytdl_file(ctx) is_corrupt = ctx.get('ytdl_corrupt') is True is_inconsistent = ctx['fragment_index'] > 0 and resume_len == 0 if is_corrupt or is_inconsistent: message = ( '.ytdl file is corrupt' if is_corrupt else 'Inconsistent state of incomplete fragment download') self.report_warning( '%s. Restarting from the beginning ...' % message) ctx['fragment_index'] = resume_len = 0 if 'ytdl_corrupt' in ctx: del ctx['ytdl_corrupt'] self._write_ytdl_file(ctx) else: self._write_ytdl_file(ctx) assert ctx['fragment_index'] == 0 dest_stream, tmpfilename = sanitize_open(tmpfilename, open_mode) ctx.update({ 'dl': dl, 'dest_stream': dest_stream, 'tmpfilename': tmpfilename, # Total complete fragments downloaded so far in bytes 'complete_frags_downloaded_bytes': resume_len, }) def _start_frag_download(self, ctx, info_dict): resume_len = ctx['complete_frags_downloaded_bytes'] total_frags = ctx['total_frags'] # This dict stores the download progress, it's updated by the progress # hook state = { 'status': 'downloading', 'downloaded_bytes': resume_len, 'fragment_index': ctx['fragment_index'], 'fragment_count': total_frags, 'filename': ctx['filename'], 'tmpfilename': ctx['tmpfilename'], } start = time.time() ctx.update({ 'started': start, # Amount of fragment's bytes downloaded by the time of the previous # frag progress hook invocation 'prev_frag_downloaded_bytes': 0, }) def frag_progress_hook(s): if s['status'] not in ('downloading', 'finished'): return time_now = time.time() state['elapsed'] = time_now - start frag_total_bytes = s.get('total_bytes') or 0 s['fragment_info_dict'] = s.pop('info_dict', {}) if not ctx['live']: estimated_size = ( (ctx['complete_frags_downloaded_bytes'] + frag_total_bytes) / (state['fragment_index'] + 1) * total_frags) state['total_bytes_estimate'] = estimated_size if s['status'] == 'finished': state['fragment_index'] += 1 ctx['fragment_index'] = state['fragment_index'] state['downloaded_bytes'] += frag_total_bytes - ctx['prev_frag_downloaded_bytes'] ctx['complete_frags_downloaded_bytes'] = state['downloaded_bytes'] ctx['prev_frag_downloaded_bytes'] = 0 else: frag_downloaded_bytes = s['downloaded_bytes'] state['downloaded_bytes'] += frag_downloaded_bytes - ctx['prev_frag_downloaded_bytes'] if not ctx['live']: state['eta'] = self.calc_eta( start, time_now, estimated_size - resume_len, state['downloaded_bytes'] - resume_len) state['speed'] = s.get('speed') or ctx.get('speed') ctx['speed'] = state['speed'] ctx['prev_frag_downloaded_bytes'] = frag_downloaded_bytes self._hook_progress(state, info_dict) ctx['dl'].add_progress_hook(frag_progress_hook) return start def _finish_frag_download(self, ctx, info_dict): ctx['dest_stream'].close() if self.__do_ytdl_file(ctx): ytdl_filename = encodeFilename(self.ytdl_filename(ctx['filename'])) if os.path.isfile(ytdl_filename): os.remove(ytdl_filename) elapsed = time.time() - ctx['started'] if ctx['tmpfilename'] == '-': downloaded_bytes = ctx['complete_frags_downloaded_bytes'] else: self.try_rename(ctx['tmpfilename'], ctx['filename']) if self.params.get('updatetime', True): filetime = ctx.get('fragment_filetime') if filetime: try: os.utime(ctx['filename'], (time.time(), filetime)) except Exception: pass downloaded_bytes = os.path.getsize(encodeFilename(ctx['filename'])) self._hook_progress({ 'downloaded_bytes': downloaded_bytes, 'total_bytes': downloaded_bytes, 'filename': ctx['filename'], 'status': 'finished', 'elapsed': elapsed, }, info_dict) def _prepare_external_frag_download(self, ctx): if 'live' not in ctx: ctx['live'] = False if not ctx['live']: total_frags_str = '%d' % ctx['total_frags'] ad_frags = ctx.get('ad_frags', 0) if ad_frags: total_frags_str += ' (not including %d ad)' % ad_frags else: total_frags_str = 'unknown (live)' self.to_screen( '[%s] Total fragments: %s' % (self.FD_NAME, total_frags_str)) tmpfilename = self.temp_name(ctx['filename']) # Should be initialized before ytdl file check ctx.update({ 'tmpfilename': tmpfilename, 'fragment_index': 0, }) def download_and_append_fragments(self, ctx, fragments, info_dict, *, pack_func=None, finish_func=None): fragment_retries = self.params.get('fragment_retries', 0) is_fatal = (lambda idx: idx == 0) if self.params.get('skip_unavailable_fragments', True) else (lambda _: True) if not pack_func: pack_func = lambda frag_content, _: frag_content def download_fragment(fragment, ctx): frag_index = ctx['fragment_index'] = fragment['frag_index'] headers = info_dict.get('http_headers', {}) byte_range = fragment.get('byte_range') if byte_range: headers['Range'] = 'bytes=%d-%d' % (byte_range['start'], byte_range['end'] - 1) # Never skip the first fragment fatal = is_fatal(fragment.get('index') or (frag_index - 1)) count, frag_content = 0, None while count <= fragment_retries: try: success, frag_content = self._download_fragment(ctx, fragment['url'], info_dict, headers) if not success: return False, frag_index break except compat_urllib_error.HTTPError as err: # Unavailable (possibly temporary) fragments may be served. # First we try to retry then either skip or abort. # See https://github.com/ytdl-org/youtube-dl/issues/10165, # https://github.com/ytdl-org/youtube-dl/issues/10448). count += 1 if count <= fragment_retries: self.report_retry_fragment(err, frag_index, count, fragment_retries) except DownloadError: # Don't retry fragment if error occurred during HTTP downloading # itself since it has own retry settings if not fatal: break raise if count > fragment_retries: if not fatal: return False, frag_index ctx['dest_stream'].close() self.report_error('Giving up after %s fragment retries' % fragment_retries) return False, frag_index return frag_content, frag_index def decrypt_fragment(fragment, frag_content): decrypt_info = fragment.get('decrypt_info') if not decrypt_info or decrypt_info['METHOD'] != 'AES-128': return frag_content iv = decrypt_info.get('IV') or compat_struct_pack('>8xq', fragment['media_sequence']) decrypt_info['KEY'] = decrypt_info.get('KEY') or self.ydl.urlopen( self._prepare_url(info_dict, info_dict.get('_decryption_key_url') or decrypt_info['URI'])).read() # Don't decrypt the content in tests since the data is explicitly truncated and it's not to a valid block # size (see https://github.com/ytdl-org/youtube-dl/pull/27660). Tests only care that the correct data downloaded, # not what it decrypts to. if self.params.get('test', False): return frag_content return AES.new(decrypt_info['KEY'], AES.MODE_CBC, iv).decrypt(frag_content) def append_fragment(frag_content, frag_index, ctx): if not frag_content: if not is_fatal(frag_index - 1): self.report_skip_fragment(frag_index) return True else: ctx['dest_stream'].close() self.report_error( 'fragment %s not found, unable to continue' % frag_index) return False self._append_fragment(ctx, pack_func(frag_content, frag_index)) return True max_workers = self.params.get('concurrent_fragment_downloads', 1) if can_threaded_download and max_workers > 1: def _download_fragment(fragment): ctx_copy = ctx.copy() frag_content, frag_index = download_fragment(fragment, ctx_copy) return fragment, frag_content, frag_index, ctx_copy.get('fragment_filename_sanitized') self.report_warning('The download speed shown is only of one thread. This is a known issue and patches are welcome') with concurrent.futures.ThreadPoolExecutor(max_workers) as pool: for fragment, frag_content, frag_index, frag_filename in pool.map(_download_fragment, fragments): ctx['fragment_filename_sanitized'] = frag_filename ctx['fragment_index'] = frag_index result = append_fragment(decrypt_fragment(fragment, frag_content), frag_index, ctx) if not result: return False else: for fragment in fragments: frag_content, frag_index = download_fragment(fragment, ctx) result = append_fragment(decrypt_fragment(fragment, frag_content), frag_index, ctx) if not result: return False if finish_func is not None: ctx['dest_stream'].write(finish_func()) ctx['dest_stream'].flush() self._finish_frag_download(ctx, info_dict) return True