[downloader/http] Randomize HTTP chunk size

This commit is contained in:
Sergey M․ 2018-02-04 07:29:11 +07:00
parent e4a60912b8
commit b91a7a4e5e
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1 changed files with 8 additions and 4 deletions

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@ -4,6 +4,7 @@ import errno
import os
import socket
import time
import random
import re
from .common import FileDownloader
@ -53,6 +54,7 @@ class HttpFD(FileDownloader):
ctx.data_len = None
ctx.block_size = self.params.get('buffersize', 1024)
ctx.start_time = time.time()
ctx.chunk_size = None
if self.params.get('continuedl', True):
# Establish possible resume length
@ -82,17 +84,19 @@ class HttpFD(FileDownloader):
req.add_header('Range', range_header)
def establish_connection():
ctx.chunk_size = (random.randint(int(chunk_size * 0.95), chunk_size)
if not is_test and chunk_size else chunk_size)
if ctx.resume_len > 0:
range_start = ctx.resume_len
if ctx.is_resume:
self.report_resuming_byte(ctx.resume_len)
ctx.open_mode = 'ab'
elif chunk_size > 0:
elif ctx.chunk_size > 0:
range_start = 0
else:
range_start = None
ctx.is_resume = False
range_end = range_start + chunk_size - 1 if chunk_size else None
range_end = range_start + ctx.chunk_size - 1 if ctx.chunk_size else None
if range_end and ctx.data_len is not None and range_end >= ctx.data_len:
range_end = ctx.data_len - 1
has_range = range_start is not None
@ -119,7 +123,7 @@ class HttpFD(FileDownloader):
content_len = int_or_none(content_range_m.group(3))
accept_content_len = (
# Non-chunked download
not chunk_size or
not ctx.chunk_size or
# Chunked download and requested piece or
# its part is promised to be served
content_range_end == range_end or
@ -297,7 +301,7 @@ class HttpFD(FileDownloader):
if is_test and byte_counter == data_len:
break
if not is_test and chunk_size and ctx.data_len is not None and byte_counter < ctx.data_len:
if not is_test and ctx.chunk_size and ctx.data_len is not None and byte_counter < ctx.data_len:
ctx.resume_len = byte_counter
# ctx.block_size = block_size
raise NextFragment()