588 lines
24 KiB
Python
588 lines
24 KiB
Python
import math
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import os
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import re
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import subprocess
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import sys
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import time
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import traceback
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if os.name == 'nt':
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import ctypes
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from .utils import *
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class FileDownloader(object):
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"""File Downloader class.
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File downloader objects are the ones responsible of downloading the
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actual video file and writing it to disk.
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File downloaders accept a lot of parameters. In order not to saturate
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the object constructor with arguments, it receives a dictionary of
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options instead.
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Available options:
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verbose: Print additional info to stdout.
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quiet: Do not print messages to stdout.
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ratelimit: Download speed limit, in bytes/sec.
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retries: Number of times to retry for HTTP error 5xx
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buffersize: Size of download buffer in bytes.
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noresizebuffer: Do not automatically resize the download buffer.
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continuedl: Try to continue downloads if possible.
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noprogress: Do not print the progress bar.
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logtostderr: Log messages to stderr instead of stdout.
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consoletitle: Display progress in console window's titlebar.
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nopart: Do not use temporary .part files.
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updatetime: Use the Last-modified header to set output file timestamps.
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test: Download only first bytes to test the downloader.
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min_filesize: Skip files smaller than this size
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max_filesize: Skip files larger than this size
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"""
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params = None
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def __init__(self, ydl, params):
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"""Create a FileDownloader object with the given options."""
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self.ydl = ydl
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self._progress_hooks = []
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self.params = params
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@staticmethod
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def format_bytes(bytes):
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if bytes is None:
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return 'N/A'
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if type(bytes) is str:
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bytes = float(bytes)
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if bytes == 0.0:
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exponent = 0
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else:
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exponent = int(math.log(bytes, 1024.0))
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suffix = ['B','KiB','MiB','GiB','TiB','PiB','EiB','ZiB','YiB'][exponent]
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converted = float(bytes) / float(1024 ** exponent)
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return '%.2f%s' % (converted, suffix)
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@staticmethod
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def format_seconds(seconds):
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(mins, secs) = divmod(seconds, 60)
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(hours, eta_mins) = divmod(mins, 60)
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if hours > 99:
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return '--:--:--'
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if hours == 0:
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return '%02d:%02d' % (mins, secs)
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else:
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return '%02d:%02d:%02d' % (hours, mins, secs)
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@staticmethod
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def calc_percent(byte_counter, data_len):
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if data_len is None:
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return '---.-%'
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return '%6s' % ('%3.1f%%' % (float(byte_counter) / float(data_len) * 100.0))
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@staticmethod
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def calc_eta(start, now, total, current):
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if total is None:
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return '--:--'
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dif = now - start
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if current == 0 or dif < 0.001: # One millisecond
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return '--:--'
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rate = float(current) / dif
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eta = int((float(total) - float(current)) / rate)
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return FileDownloader.format_seconds(eta)
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@staticmethod
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def calc_speed(start, now, bytes):
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dif = now - start
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if bytes == 0 or dif < 0.001: # One millisecond
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return '%10s' % '---b/s'
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return '%10s' % ('%s/s' % FileDownloader.format_bytes(float(bytes) / dif))
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@staticmethod
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def best_block_size(elapsed_time, bytes):
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new_min = max(bytes / 2.0, 1.0)
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new_max = min(max(bytes * 2.0, 1.0), 4194304) # Do not surpass 4 MB
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if elapsed_time < 0.001:
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return int(new_max)
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rate = bytes / elapsed_time
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if rate > new_max:
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return int(new_max)
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if rate < new_min:
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return int(new_min)
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return int(rate)
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@staticmethod
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def parse_bytes(bytestr):
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"""Parse a string indicating a byte quantity into an integer."""
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matchobj = re.match(r'(?i)^(\d+(?:\.\d+)?)([kMGTPEZY]?)$', bytestr)
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if matchobj is None:
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return None
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number = float(matchobj.group(1))
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multiplier = 1024.0 ** 'bkmgtpezy'.index(matchobj.group(2).lower())
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return int(round(number * multiplier))
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def to_screen(self, *args, **kargs):
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self.ydl.to_screen(*args, **kargs)
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def to_stderr(self, message):
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self.ydl.to_screen(message)
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def to_cons_title(self, message):
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"""Set console/terminal window title to message."""
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if not self.params.get('consoletitle', False):
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return
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if os.name == 'nt' and ctypes.windll.kernel32.GetConsoleWindow():
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# c_wchar_p() might not be necessary if `message` is
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# already of type unicode()
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ctypes.windll.kernel32.SetConsoleTitleW(ctypes.c_wchar_p(message))
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elif 'TERM' in os.environ:
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self.to_screen('\033]0;%s\007' % message, skip_eol=True)
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def trouble(self, *args, **kargs):
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self.ydl.trouble(*args, **kargs)
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def report_warning(self, *args, **kargs):
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self.ydl.report_warning(*args, **kargs)
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def report_error(self, *args, **kargs):
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self.ydl.report_error(*args, **kargs)
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def slow_down(self, start_time, byte_counter):
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"""Sleep if the download speed is over the rate limit."""
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rate_limit = self.params.get('ratelimit', None)
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if rate_limit is None or byte_counter == 0:
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return
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now = time.time()
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elapsed = now - start_time
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if elapsed <= 0.0:
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return
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speed = float(byte_counter) / elapsed
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if speed > rate_limit:
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time.sleep((byte_counter - rate_limit * (now - start_time)) / rate_limit)
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def temp_name(self, filename):
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"""Returns a temporary filename for the given filename."""
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if self.params.get('nopart', False) or filename == u'-' or \
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(os.path.exists(encodeFilename(filename)) and not os.path.isfile(encodeFilename(filename))):
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return filename
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return filename + u'.part'
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def undo_temp_name(self, filename):
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if filename.endswith(u'.part'):
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return filename[:-len(u'.part')]
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return filename
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def try_rename(self, old_filename, new_filename):
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try:
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if old_filename == new_filename:
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return
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os.rename(encodeFilename(old_filename), encodeFilename(new_filename))
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except (IOError, OSError) as err:
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self.report_error(u'unable to rename file')
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def try_utime(self, filename, last_modified_hdr):
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"""Try to set the last-modified time of the given file."""
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if last_modified_hdr is None:
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return
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if not os.path.isfile(encodeFilename(filename)):
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return
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timestr = last_modified_hdr
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if timestr is None:
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return
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filetime = timeconvert(timestr)
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if filetime is None:
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return filetime
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# Ignore obviously invalid dates
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if filetime == 0:
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return
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try:
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os.utime(filename, (time.time(), filetime))
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except:
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pass
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return filetime
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def report_destination(self, filename):
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"""Report destination filename."""
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self.to_screen(u'[download] Destination: ' + filename)
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def report_progress(self, percent_str, data_len_str, speed_str, eta_str):
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"""Report download progress."""
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if self.params.get('noprogress', False):
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return
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clear_line = (u'\x1b[K' if sys.stderr.isatty() and os.name != 'nt' else u'')
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if self.params.get('progress_with_newline', False):
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self.to_screen(u'[download] %s of %s at %s ETA %s' %
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(percent_str, data_len_str, speed_str, eta_str))
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else:
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self.to_screen(u'\r%s[download] %s of %s at %s ETA %s' %
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(clear_line, percent_str, data_len_str, speed_str, eta_str), skip_eol=True)
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self.to_cons_title(u'youtube-dl - %s of %s at %s ETA %s' %
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(percent_str.strip(), data_len_str.strip(), speed_str.strip(), eta_str.strip()))
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def report_resuming_byte(self, resume_len):
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"""Report attempt to resume at given byte."""
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self.to_screen(u'[download] Resuming download at byte %s' % resume_len)
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def report_retry(self, count, retries):
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"""Report retry in case of HTTP error 5xx"""
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self.to_screen(u'[download] Got server HTTP error. Retrying (attempt %d of %d)...' % (count, retries))
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def report_file_already_downloaded(self, file_name):
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"""Report file has already been fully downloaded."""
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try:
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self.to_screen(u'[download] %s has already been downloaded' % file_name)
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except (UnicodeEncodeError) as err:
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self.to_screen(u'[download] The file has already been downloaded')
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def report_unable_to_resume(self):
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"""Report it was impossible to resume download."""
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self.to_screen(u'[download] Unable to resume')
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def report_finish(self, data_len_str, tot_time):
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"""Report download finished."""
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if self.params.get('noprogress', False):
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self.to_screen(u'[download] Download completed')
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else:
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clear_line = (u'\x1b[K' if sys.stderr.isatty() and os.name != 'nt' else u'')
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self.to_screen(u'\r%s[download] 100%% of %s in %s' %
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(clear_line, data_len_str, self.format_seconds(tot_time)))
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def _download_with_rtmpdump(self, filename, url, player_url, page_url, play_path, tc_url):
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self.report_destination(filename)
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tmpfilename = self.temp_name(filename)
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# Check for rtmpdump first
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try:
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subprocess.call(['rtmpdump', '-h'], stdout=(open(os.path.devnull, 'w')), stderr=subprocess.STDOUT)
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except (OSError, IOError):
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self.report_error(u'RTMP download detected but "rtmpdump" could not be run')
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return False
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verbosity_option = '--verbose' if self.params.get('verbose', False) else '--quiet'
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# Download using rtmpdump. rtmpdump returns exit code 2 when
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# the connection was interrumpted and resuming appears to be
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# possible. This is part of rtmpdump's normal usage, AFAIK.
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basic_args = ['rtmpdump', verbosity_option, '-r', url, '-o', tmpfilename]
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if player_url is not None:
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basic_args += ['--swfVfy', player_url]
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if page_url is not None:
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basic_args += ['--pageUrl', page_url]
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if play_path is not None:
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basic_args += ['--playpath', play_path]
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if tc_url is not None:
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basic_args += ['--tcUrl', url]
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args = basic_args + [[], ['--resume', '--skip', '1']][self.params.get('continuedl', False)]
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if self.params.get('verbose', False):
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try:
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import pipes
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shell_quote = lambda args: ' '.join(map(pipes.quote, args))
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except ImportError:
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shell_quote = repr
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self.to_screen(u'[debug] rtmpdump command line: ' + shell_quote(args))
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retval = subprocess.call(args)
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while retval == 2 or retval == 1:
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prevsize = os.path.getsize(encodeFilename(tmpfilename))
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self.to_screen(u'\r[rtmpdump] %s bytes' % prevsize, skip_eol=True)
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time.sleep(5.0) # This seems to be needed
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retval = subprocess.call(basic_args + ['-e'] + [[], ['-k', '1']][retval == 1])
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cursize = os.path.getsize(encodeFilename(tmpfilename))
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if prevsize == cursize and retval == 1:
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break
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# Some rtmp streams seem abort after ~ 99.8%. Don't complain for those
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if prevsize == cursize and retval == 2 and cursize > 1024:
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self.to_screen(u'\r[rtmpdump] Could not download the whole video. This can happen for some advertisements.')
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retval = 0
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break
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if retval == 0:
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fsize = os.path.getsize(encodeFilename(tmpfilename))
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self.to_screen(u'\r[rtmpdump] %s bytes' % fsize)
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self.try_rename(tmpfilename, filename)
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self._hook_progress({
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'downloaded_bytes': fsize,
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'total_bytes': fsize,
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'filename': filename,
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'status': 'finished',
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})
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return True
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else:
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self.to_stderr(u"\n")
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self.report_error(u'rtmpdump exited with code %d' % retval)
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return False
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def _download_with_mplayer(self, filename, url):
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self.report_destination(filename)
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tmpfilename = self.temp_name(filename)
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args = ['mplayer', '-really-quiet', '-vo', 'null', '-vc', 'dummy', '-dumpstream', '-dumpfile', tmpfilename, url]
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# Check for mplayer first
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try:
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subprocess.call(['mplayer', '-h'], stdout=(open(os.path.devnull, 'w')), stderr=subprocess.STDOUT)
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except (OSError, IOError):
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self.report_error(u'MMS or RTSP download detected but "%s" could not be run' % args[0] )
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return False
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# Download using mplayer.
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retval = subprocess.call(args)
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if retval == 0:
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fsize = os.path.getsize(encodeFilename(tmpfilename))
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self.to_screen(u'\r[%s] %s bytes' % (args[0], fsize))
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self.try_rename(tmpfilename, filename)
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self._hook_progress({
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'downloaded_bytes': fsize,
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'total_bytes': fsize,
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'filename': filename,
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'status': 'finished',
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})
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return True
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else:
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self.to_stderr(u"\n")
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self.report_error(u'mplayer exited with code %d' % retval)
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return False
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def _download_m3u8_with_ffmpeg(self, filename, url):
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self.report_destination(filename)
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tmpfilename = self.temp_name(filename)
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args = ['ffmpeg', '-y', '-i', url, '-f', 'mp4', tmpfilename]
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# Check for ffmpeg first
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try:
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subprocess.call(['ffmpeg', '-h'], stdout=(open(os.path.devnull, 'w')), stderr=subprocess.STDOUT)
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except (OSError, IOError):
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self.report_error(u'm3u8 download detected but "%s" could not be run' % args[0] )
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return False
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retval = subprocess.call(args)
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if retval == 0:
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fsize = os.path.getsize(encodeFilename(tmpfilename))
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self.to_screen(u'\r[%s] %s bytes' % (args[0], fsize))
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self.try_rename(tmpfilename, filename)
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self._hook_progress({
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'downloaded_bytes': fsize,
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'total_bytes': fsize,
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'filename': filename,
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'status': 'finished',
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})
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return True
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else:
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self.to_stderr(u"\n")
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self.report_error(u'ffmpeg exited with code %d' % retval)
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return False
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def _do_download(self, filename, info_dict):
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url = info_dict['url']
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# Check file already present
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if self.params.get('continuedl', False) and os.path.isfile(encodeFilename(filename)) and not self.params.get('nopart', False):
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self.report_file_already_downloaded(filename)
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self._hook_progress({
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'filename': filename,
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'status': 'finished',
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})
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return True
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# Attempt to download using rtmpdump
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if url.startswith('rtmp'):
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return self._download_with_rtmpdump(filename, url,
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info_dict.get('player_url', None),
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info_dict.get('page_url', None),
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info_dict.get('play_path', None),
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info_dict.get('tc_url', None))
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# Attempt to download using mplayer
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if url.startswith('mms') or url.startswith('rtsp'):
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return self._download_with_mplayer(filename, url)
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# m3u8 manifest are downloaded with ffmpeg
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if determine_ext(url) == u'm3u8':
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return self._download_m3u8_with_ffmpeg(filename, url)
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tmpfilename = self.temp_name(filename)
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stream = None
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# Do not include the Accept-Encoding header
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headers = {'Youtubedl-no-compression': 'True'}
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if 'user_agent' in info_dict:
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headers['Youtubedl-user-agent'] = info_dict['user_agent']
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basic_request = compat_urllib_request.Request(url, None, headers)
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request = compat_urllib_request.Request(url, None, headers)
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if self.params.get('test', False):
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request.add_header('Range','bytes=0-10240')
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# Establish possible resume length
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if os.path.isfile(encodeFilename(tmpfilename)):
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resume_len = os.path.getsize(encodeFilename(tmpfilename))
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else:
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resume_len = 0
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open_mode = 'wb'
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if resume_len != 0:
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if self.params.get('continuedl', False):
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self.report_resuming_byte(resume_len)
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request.add_header('Range','bytes=%d-' % resume_len)
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open_mode = 'ab'
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else:
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resume_len = 0
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count = 0
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retries = self.params.get('retries', 0)
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while count <= retries:
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# Establish connection
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try:
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if count == 0 and 'urlhandle' in info_dict:
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data = info_dict['urlhandle']
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data = compat_urllib_request.urlopen(request)
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break
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except (compat_urllib_error.HTTPError, ) as err:
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if (err.code < 500 or err.code >= 600) and err.code != 416:
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# Unexpected HTTP error
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raise
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elif err.code == 416:
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# Unable to resume (requested range not satisfiable)
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try:
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# Open the connection again without the range header
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data = compat_urllib_request.urlopen(basic_request)
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content_length = data.info()['Content-Length']
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except (compat_urllib_error.HTTPError, ) as err:
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if err.code < 500 or err.code >= 600:
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raise
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else:
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# Examine the reported length
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if (content_length is not None and
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(resume_len - 100 < int(content_length) < resume_len + 100)):
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# The file had already been fully downloaded.
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# Explanation to the above condition: in issue #175 it was revealed that
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# YouTube sometimes adds or removes a few bytes from the end of the file,
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# changing the file size slightly and causing problems for some users. So
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# I decided to implement a suggested change and consider the file
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# completely downloaded if the file size differs less than 100 bytes from
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# the one in the hard drive.
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self.report_file_already_downloaded(filename)
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self.try_rename(tmpfilename, filename)
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self._hook_progress({
|
|
'filename': filename,
|
|
'status': 'finished',
|
|
})
|
|
return True
|
|
else:
|
|
# The length does not match, we start the download over
|
|
self.report_unable_to_resume()
|
|
open_mode = 'wb'
|
|
break
|
|
# Retry
|
|
count += 1
|
|
if count <= retries:
|
|
self.report_retry(count, retries)
|
|
|
|
if count > retries:
|
|
self.report_error(u'giving up after %s retries' % retries)
|
|
return False
|
|
|
|
data_len = data.info().get('Content-length', None)
|
|
if data_len is not None:
|
|
data_len = int(data_len) + resume_len
|
|
min_data_len = self.params.get("min_filesize", None)
|
|
max_data_len = self.params.get("max_filesize", None)
|
|
if min_data_len is not None and data_len < min_data_len:
|
|
self.to_screen(u'\r[download] File is smaller than min-filesize (%s bytes < %s bytes). Aborting.' % (data_len, min_data_len))
|
|
return False
|
|
if max_data_len is not None and data_len > max_data_len:
|
|
self.to_screen(u'\r[download] File is larger than max-filesize (%s bytes > %s bytes). Aborting.' % (data_len, max_data_len))
|
|
return False
|
|
|
|
data_len_str = self.format_bytes(data_len)
|
|
byte_counter = 0 + resume_len
|
|
block_size = self.params.get('buffersize', 1024)
|
|
start = time.time()
|
|
while True:
|
|
# Download and write
|
|
before = time.time()
|
|
data_block = data.read(block_size)
|
|
after = time.time()
|
|
if len(data_block) == 0:
|
|
break
|
|
byte_counter += len(data_block)
|
|
|
|
# Open file just in time
|
|
if stream is None:
|
|
try:
|
|
(stream, tmpfilename) = sanitize_open(tmpfilename, open_mode)
|
|
assert stream is not None
|
|
filename = self.undo_temp_name(tmpfilename)
|
|
self.report_destination(filename)
|
|
except (OSError, IOError) as err:
|
|
self.report_error(u'unable to open for writing: %s' % str(err))
|
|
return False
|
|
try:
|
|
stream.write(data_block)
|
|
except (IOError, OSError) as err:
|
|
self.to_stderr(u"\n")
|
|
self.report_error(u'unable to write data: %s' % str(err))
|
|
return False
|
|
if not self.params.get('noresizebuffer', False):
|
|
block_size = self.best_block_size(after - before, len(data_block))
|
|
|
|
# Progress message
|
|
speed_str = self.calc_speed(start, time.time(), byte_counter - resume_len)
|
|
if data_len is None:
|
|
self.report_progress('Unknown %', data_len_str, speed_str, 'Unknown ETA')
|
|
else:
|
|
percent_str = self.calc_percent(byte_counter, data_len)
|
|
eta_str = self.calc_eta(start, time.time(), data_len - resume_len, byte_counter - resume_len)
|
|
self.report_progress(percent_str, data_len_str, speed_str, eta_str)
|
|
|
|
self._hook_progress({
|
|
'downloaded_bytes': byte_counter,
|
|
'total_bytes': data_len,
|
|
'tmpfilename': tmpfilename,
|
|
'filename': filename,
|
|
'status': 'downloading',
|
|
})
|
|
|
|
# Apply rate limit
|
|
self.slow_down(start, byte_counter - resume_len)
|
|
|
|
if stream is None:
|
|
self.to_stderr(u"\n")
|
|
self.report_error(u'Did not get any data blocks')
|
|
return False
|
|
stream.close()
|
|
self.report_finish(data_len_str, (time.time() - start))
|
|
if data_len is not None and byte_counter != data_len:
|
|
raise ContentTooShortError(byte_counter, int(data_len))
|
|
self.try_rename(tmpfilename, filename)
|
|
|
|
# Update file modification time
|
|
if self.params.get('updatetime', True):
|
|
info_dict['filetime'] = self.try_utime(filename, data.info().get('last-modified', None))
|
|
|
|
self._hook_progress({
|
|
'downloaded_bytes': byte_counter,
|
|
'total_bytes': byte_counter,
|
|
'filename': filename,
|
|
'status': 'finished',
|
|
})
|
|
|
|
return True
|
|
|
|
def _hook_progress(self, status):
|
|
for ph in self._progress_hooks:
|
|
ph(status)
|
|
|
|
def add_progress_hook(self, ph):
|
|
""" ph gets called on download progress, with a dictionary with the entries
|
|
* filename: The final filename
|
|
* status: One of "downloading" and "finished"
|
|
|
|
It can also have some of the following entries:
|
|
|
|
* downloaded_bytes: Bytes on disks
|
|
* total_bytes: Total bytes, None if unknown
|
|
* tmpfilename: The filename we're currently writing to
|
|
|
|
Hooks are guaranteed to be called at least once (with status "finished")
|
|
if the download is successful.
|
|
"""
|
|
self._progress_hooks.append(ph)
|