video routing: Range request missing content when connection closed

googlevideo sometimes doesn't send all video content and closes
the connection. Retry with a range request for the bytes needed
a maximum of three times.

Fixes first type of #40

Signed-off-by: Jesús <heckyel@hyperbola.info>
This commit is contained in:
James Taylor 2020-12-18 21:17:06 -08:00 committed by Jesús
parent 6b6a6653a0
commit afb2aca460
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138
server.py
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@ -19,6 +19,7 @@ import socks, sockshandler
import subprocess
import re
import sys
import time
def youtu_be(env, start_response):
@ -31,13 +32,33 @@ def youtu_be(env, start_response):
yield from yt_app(env, start_response)
RANGE_RE = re.compile(r'bytes=(\d+-(?:\d+)?)')
def parse_range(range_header, content_length):
# Range header can be like bytes=200-1000 or bytes=200-
# amount_received is the length of bytes from the range that have already
# been received
match = RANGE_RE.fullmatch(range_header.strip())
if not match:
print('Unsupported range header format:', range_header)
return None
start, end = match.group(1).split('-')
start_byte = int(start)
if not end:
end_byte = start_byte + content_length - 1
else:
end_byte = int(end)
return start_byte, end_byte
def proxy_site(env, start_response, video=False):
headers = {
send_headers = {
'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64)',
'Accept': '*/*',
}
current_range_start = 0
range_end = None
if 'HTTP_RANGE' in env:
headers['Range'] = env['HTTP_RANGE']
send_headers['Range'] = env['HTTP_RANGE']
url = "https://" + env['SERVER_NAME'] + env['PATH_INFO']
# remove /name portion
@ -46,37 +67,94 @@ def proxy_site(env, start_response, video=False):
if env['QUERY_STRING']:
url += '?' + env['QUERY_STRING']
if video:
params = urllib.parse.parse_qs(env['QUERY_STRING'])
params_use_tor = int(params.get('use_tor', '0')[0])
use_tor = (settings.route_tor == 2) or params_use_tor
response, cleanup_func = util.fetch_url_response(url, headers,
use_tor=use_tor,
max_redirects=10)
else:
response, cleanup_func = util.fetch_url_response(url, headers)
try_num = 1
first_attempt = True
current_attempt_position = 0
while try_num <= 3: # Try a given byte position three times
if not first_attempt:
print('(Try %d)' % try_num, 'Trying with', send_headers['Range'])
headers = response.getheaders()
if isinstance(headers, urllib3._collections.HTTPHeaderDict):
headers = headers.items()
if video:
params = urllib.parse.parse_qs(env['QUERY_STRING'])
params_use_tor = int(params.get('use_tor', '0')[0])
use_tor = (settings.route_tor == 2) or params_use_tor
response, cleanup_func = util.fetch_url_response(url, send_headers,
use_tor=use_tor,
max_redirects=10)
else:
response, cleanup_func = util.fetch_url_response(url, send_headers)
start_response(str(response.status) + ' ' + response.reason, headers)
while True:
# a bit over 3 seconds of 360p video
# we want each TCP packet to transmit in large multiples,
# such as 65,536, so we shouldn't read in small chunks
# such as 8192 lest that causes the socket library to limit the
# TCP window size
# Might need fine-tuning, since this gives us 4*65536
# The tradeoff is that larger values (such as 6 seconds) only
# allows video to buffer in those increments, meaning user must wait
# until the entire chunk is downloaded before video starts playing
content_part = response.read(32*8192)
if not content_part:
response_headers = response.getheaders()
if isinstance(response_headers, urllib3._collections.HTTPHeaderDict):
response_headers = response_headers.items()
if first_attempt:
start_response(str(response.status) + ' ' + response.reason,
response_headers)
content_length = int(dict(response_headers).get('Content-Length', 0))
if response.status >= 400:
print('Error: Youtube returned "%d %s" while routing %s' % (
response.status, response.reason, url.split('?')[0]))
total_received = 0
retry = False
while True:
# a bit over 3 seconds of 360p video
# we want each TCP packet to transmit in large multiples,
# such as 65,536, so we shouldn't read in small chunks
# such as 8192 lest that causes the socket library to limit the
# TCP window size
# Might need fine-tuning, since this gives us 4*65536
# The tradeoff is that larger values (such as 6 seconds) only
# allows video to buffer in those increments, meaning user must
# wait until the entire chunk is downloaded before video starts
# playing
content_part = response.read(32*8192)
total_received += len(content_part)
if not content_part:
# Sometimes Youtube closes the connection before sending all of
# the content. Retry with a range request for the missing
# content. See
# https://github.com/user234683/youtube-local/issues/40
if total_received < content_length:
if 'Range' in send_headers:
int_range = parse_range(send_headers['Range'],
content_length)
if not int_range: # give up b/c unrecognized range
break
start, end = int_range
else:
start, end = 0, (content_length - 1)
fail_byte = start + total_received
send_headers['Range'] = 'bytes=%d-%d' % (fail_byte, end)
print(
'Warning: Youtube closed the connection before byte',
str(fail_byte) + '.', 'Expected', start+content_length,
'bytes.'
)
retry = True
first_attempt = False
if fail_byte == current_attempt_position:
try_num += 1
else:
try_num = 1
current_attempt_position = fail_byte
break
yield content_part
cleanup_func(response)
if retry:
# Youtube will return 503 Service Unavailable if you do a bunch
# of range requests too quickly.
time.sleep(1)
continue
else:
break
yield content_part
cleanup_func(response)
else: # no break
print('Error: Youtube closed the connection before',
'providing all content. Retried three times:', url.split('?')[0])
def proxy_video(env, start_response):