from __future__ import division, unicode_literals
import io
import itertools
import time
from .fragment import FragmentFD
from ..compat import (
compat_b64decode,
compat_etree_fromstring,
compat_urlparse,
compat_urllib_error,
compat_urllib_parse_urlparse,
compat_struct_pack,
compat_struct_unpack,
)
from ..utils import (
fix_xml_ampersands,
xpath_text,
)
class DataTruncatedError(Exception):
pass
class FlvReader(io.BytesIO):
"""
Reader for Flv files
The file format is documented in https://www.adobe.com/devnet/f4v.html
"""
def read_bytes(self, n):
data = self.read(n)
if len(data) < n:
raise DataTruncatedError(
'FlvReader error: need %d bytes while only %d bytes got' % (
n, len(data)))
return data
# Utility functions for reading numbers and strings
def read_unsigned_long_long(self):
return compat_struct_unpack('!Q', self.read_bytes(8))[0]
def read_unsigned_int(self):
return compat_struct_unpack('!I', self.read_bytes(4))[0]
def read_unsigned_char(self):
return compat_struct_unpack('!B', self.read_bytes(1))[0]
def read_string(self):
res = b''
while True:
char = self.read_bytes(1)
if char == b'\x00':
break
res += char
return res
def read_box_info(self):
"""
Read a box and return the info as a tuple: (box_size, box_type, box_data)
"""
real_size = size = self.read_unsigned_int()
box_type = self.read_bytes(4)
header_end = 8
if size == 1:
real_size = self.read_unsigned_long_long()
header_end = 16
return real_size, box_type, self.read_bytes(real_size - header_end)
def read_asrt(self):
# version
self.read_unsigned_char()
# flags
self.read_bytes(3)
quality_entry_count = self.read_unsigned_char()
# QualityEntryCount
for i in range(quality_entry_count):
self.read_string()
segment_run_count = self.read_unsigned_int()
segments = []
for i in range(segment_run_count):
first_segment = self.read_unsigned_int()
fragments_per_segment = self.read_unsigned_int()
segments.append((first_segment, fragments_per_segment))
return {
'segment_run': segments,
}
def read_afrt(self):
# version
self.read_unsigned_char()
# flags
self.read_bytes(3)
# time scale
self.read_unsigned_int()
quality_entry_count = self.read_unsigned_char()
# QualitySegmentUrlModifiers
for i in range(quality_entry_count):
self.read_string()
fragments_count = self.read_unsigned_int()
fragments = []
for i in range(fragments_count):
first = self.read_unsigned_int()
first_ts = self.read_unsigned_long_long()
duration = self.read_unsigned_int()
if duration == 0:
discontinuity_indicator = self.read_unsigned_char()
else:
discontinuity_indicator = None
fragments.append({
'first': first,
'ts': first_ts,
'duration': duration,
'discontinuity_indicator': discontinuity_indicator,
})
return {
'fragments': fragments,
}
def read_abst(self):
# version
self.read_unsigned_char()
# flags
self.read_bytes(3)
self.read_unsigned_int() # BootstrapinfoVersion
# Profile,Live,Update,Reserved
flags = self.read_unsigned_char()
live = flags & 0x20 != 0
# time scale
self.read_unsigned_int()
# CurrentMediaTime
self.read_unsigned_long_long()
# SmpteTimeCodeOffset
self.read_unsigned_long_long()
self.read_string() # MovieIdentifier
server_count = self.read_unsigned_char()
# ServerEntryTable
for i in range(server_count):
self.read_string()
quality_count = self.read_unsigned_char()
# QualityEntryTable
for i in range(quality_count):
self.read_string()
# DrmData
self.read_string()
# MetaData
self.read_string()
segments_count = self.read_unsigned_char()
segments = []
for i in range(segments_count):
box_size, box_type, box_data = self.read_box_info()
assert box_type == b'asrt'
segment = FlvReader(box_data).read_asrt()
segments.append(segment)
fragments_run_count = self.read_unsigned_char()
fragments = []
for i in range(fragments_run_count):
box_size, box_type, box_data = self.read_box_info()
assert box_type == b'afrt'
fragments.append(FlvReader(box_data).read_afrt())
return {
'segments': segments,
'fragments': fragments,
'live': live,
}
def read_bootstrap_info(self):
total_size, box_type, box_data = self.read_box_info()
assert box_type == b'abst'
return FlvReader(box_data).read_abst()
def read_bootstrap_info(bootstrap_bytes):
return FlvReader(bootstrap_bytes).read_bootstrap_info()
def build_fragments_list(boot_info):
""" Return a list of (segment, fragment) for each fragment in the video """
res = []
segment_run_table = boot_info['segments'][0]
fragment_run_entry_table = boot_info['fragments'][0]['fragments']
first_frag_number = fragment_run_entry_table[0]['first']
fragments_counter = itertools.count(first_frag_number)
for segment, fragments_count in segment_run_table['segment_run']:
# In some live HDS streams (for example Rai), `fragments_count` is
# abnormal and causing out-of-memory errors. It's OK to change the
# number of fragments for live streams as they are updated periodically
if fragments_count == 4294967295 and boot_info['live']:
fragments_count = 2
for _ in range(fragments_count):
res.append((segment, next(fragments_counter)))
if boot_info['live']:
res = res[-2:]
return res
def write_unsigned_int(stream, val):
stream.write(compat_struct_pack('!I', val))
def write_unsigned_int_24(stream, val):
stream.write(compat_struct_pack('!I', val)[1:])
def write_flv_header(stream):
"""Writes the FLV header to stream"""
# FLV header
stream.write(b'FLV\x01')
stream.write(b'\x05')
stream.write(b'\x00\x00\x00\x09')
stream.write(b'\x00\x00\x00\x00')
def write_metadata_tag(stream, metadata):
"""Writes optional metadata tag to stream"""
SCRIPT_TAG = b'\x12'
FLV_TAG_HEADER_LEN = 11
if metadata:
stream.write(SCRIPT_TAG)
write_unsigned_int_24(stream, len(metadata))
stream.write(b'\x00\x00\x00\x00\x00\x00\x00')
stream.write(metadata)
write_unsigned_int(stream, FLV_TAG_HEADER_LEN + len(metadata))
def remove_encrypted_media(media):
return list(filter(lambda e: 'drmAdditionalHeaderId' not in e.attrib
and 'drmAdditionalHeaderSetId' not in e.attrib,
media))
def _add_ns(prop, ver=1):
return '{http://ns.adobe.com/f4m/%d.0}%s' % (ver, prop)
def get_base_url(manifest):
base_url = xpath_text(
manifest, [_add_ns('baseURL'), _add_ns('baseURL', 2)],
'base URL', default=None)
if base_url:
base_url = base_url.strip()
return base_url
class F4mFD(FragmentFD):
"""
A downloader for f4m manifests or AdobeHDS.
"""
FD_NAME = 'f4m'
def _get_unencrypted_media(self, doc):
media = doc.findall(_add_ns('media'))
if not media:
self.report_error('No media found')
for e in (doc.findall(_add_ns('drmAdditionalHeader'))
+ doc.findall(_add_ns('drmAdditionalHeaderSet'))):
# If id attribute is missing it's valid for all media nodes
# without drmAdditionalHeaderId or drmAdditionalHeaderSetId attribute
if 'id' not in e.attrib:
self.report_error('Missing ID in f4m DRM')
media = remove_encrypted_media(media)
if not media:
self.report_error('Unsupported DRM')
return media
def _get_bootstrap_from_url(self, bootstrap_url):
bootstrap = self.ydl.urlopen(bootstrap_url).read()
return read_bootstrap_info(bootstrap)
def _update_live_fragments(self, bootstrap_url, latest_fragment):
fragments_list = []
retries = 30
while (not fragments_list) and (retries > 0):
boot_info = self._get_bootstrap_from_url(bootstrap_url)
fragments_list = build_fragments_list(boot_info)
fragments_list = [f for f in fragments_list if f[1] > latest_fragment]
if not fragments_list:
# Retry after a while
time.sleep(5.0)
retries -= 1
if not fragments_list:
self.report_error('Failed to update fragments')
return fragments_list
def _parse_bootstrap_node(self, node, base_url):
# Sometimes non empty inline bootstrap info can be specified along
# with bootstrap url attribute (e.g. dummy inline bootstrap info
# contains whitespace characters in [1]). We will prefer bootstrap
# url over inline bootstrap info when present.
# 1. http://live-1-1.rutube.ru/stream/1024/HDS/SD/C2NKsS85HQNckgn5HdEmOQ/1454167650/S-s604419906/move/four/dirs/upper/1024-576p.f4m
bootstrap_url = node.get('url')
if bootstrap_url:
bootstrap_url = compat_urlparse.urljoin(
base_url, bootstrap_url)
boot_info = self._get_bootstrap_from_url(bootstrap_url)
else:
bootstrap_url = None
bootstrap = compat_b64decode(node.text)
boot_info = read_bootstrap_info(bootstrap)
return boot_info, bootstrap_url
def real_download(self, filename, info_dict):
man_url = info_dict['url']
requested_bitrate = info_dict.get('tbr')
self.to_screen('[%s] Downloading f4m manifest' % self.FD_NAME)
urlh = self.ydl.urlopen(self._prepare_url(info_dict, man_url))
man_url = urlh.geturl()
# Some manifests may be malformed, e.g. prosiebensat1 generated manifests
# (see https://github.com/ytdl-org/youtube-dl/issues/6215#issuecomment-121704244
# and https://github.com/ytdl-org/youtube-dl/issues/7823)
manifest = fix_xml_ampersands(urlh.read().decode('utf-8', 'ignore')).strip()
doc = compat_etree_fromstring(manifest)
formats = [(int(f.attrib.get('bitrate', -1)), f)
for f in self._get_unencrypted_media(doc)]
if requested_bitrate is None or len(formats) == 1:
# get the best format
formats = sorted(formats, key=lambda f: f[0])
rate, media = formats[-1]
else:
rate, media = list(filter(
lambda f: int(f[0]) == requested_bitrate, formats))[0]
# Prefer baseURL for relative URLs as per 11.2 of F4M 3.0 spec.
man_base_url = get_base_url(doc) or man_url
base_url = compat_urlparse.urljoin(man_base_url, media.attrib['url'])
bootstrap_node = doc.find(_add_ns('bootstrapInfo'))
boot_info, bootstrap_url = self._parse_bootstrap_node(
bootstrap_node, man_base_url)
live = boot_info['live']
metadata_node = media.find(_add_ns('metadata'))
if metadata_node is not None:
metadata = compat_b64decode(metadata_node.text)
else:
metadata = None
fragments_list = build_fragments_list(boot_info)
test = self.params.get('test', False)
if test:
# We only download the first fragment
fragments_list = fragments_list[:1]
total_frags = len(fragments_list)
# For some akamai manifests we'll need to add a query to the fragment url
akamai_pv = xpath_text(doc, _add_ns('pv-2.0'))
ctx = {
'filename': filename,
'total_frags': total_frags,
'live': live,
}
self._prepare_frag_download(ctx)
dest_stream = ctx['dest_stream']
if ctx['complete_frags_downloaded_bytes'] == 0:
write_flv_header(dest_stream)
if not live:
write_metadata_tag(dest_stream, metadata)
base_url_parsed = compat_urllib_parse_urlparse(base_url)
self._start_frag_download(ctx)
frag_index = 0
while fragments_list:
seg_i, frag_i = fragments_list.pop(0)
frag_index += 1
if frag_index <= ctx['fragment_index']:
continue
name = 'Seg%d-Frag%d' % (seg_i, frag_i)
query = []
if base_url_parsed.query:
query.append(base_url_parsed.query)
if akamai_pv:
query.append(akamai_pv.strip(';'))
if info_dict.get('extra_param_to_segment_url'):
query.append(info_dict['extra_param_to_segment_url'])
url_parsed = base_url_parsed._replace(path=base_url_parsed.path + name, query='&'.join(query))
try:
success, down_data = self._download_fragment(ctx, url_parsed.geturl(), info_dict)
if not success:
return False
reader = FlvReader(down_data)
while True:
try:
_, box_type, box_data = reader.read_box_info()
except DataTruncatedError:
if test:
# In tests, segments may be truncated, and thus
# FlvReader may not be able to parse the whole
# chunk. If so, write the segment as is
# See https://github.com/ytdl-org/youtube-dl/issues/9214
dest_stream.write(down_data)
break
raise
if box_type == b'mdat':
self._append_fragment(ctx, box_data)
break
except (compat_urllib_error.HTTPError, ) as err:
if live and (err.code == 404 or err.code == 410):
# We didn't keep up with the live window. Continue
# with the next available fragment.
msg = 'Fragment %d unavailable' % frag_i
self.report_warning(msg)
fragments_list = []
else:
raise
if not fragments_list and not test and live and bootstrap_url:
fragments_list = self._update_live_fragments(bootstrap_url, frag_i)
total_frags += len(fragments_list)
if fragments_list and (fragments_list[0][1] > frag_i + 1):
msg = 'Missed %d fragments' % (fragments_list[0][1] - (frag_i + 1))
self.report_warning(msg)
self._finish_frag_download(ctx)
return True