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[youtubedl] / youtube_dl / FileDownloader.py
1 import os
2 import re
3 import subprocess
4 import sys
5 import time
6
7 from .utils import (
8 compat_urllib_error,
9 compat_urllib_request,
10 ContentTooShortError,
11 determine_ext,
12 encodeFilename,
13 format_bytes,
14 sanitize_open,
15 timeconvert,
16 )
17
18
19 class FileDownloader(object):
20 """File Downloader class.
21
22 File downloader objects are the ones responsible of downloading the
23 actual video file and writing it to disk.
24
25 File downloaders accept a lot of parameters. In order not to saturate
26 the object constructor with arguments, it receives a dictionary of
27 options instead.
28
29 Available options:
30
31 verbose: Print additional info to stdout.
32 quiet: Do not print messages to stdout.
33 ratelimit: Download speed limit, in bytes/sec.
34 retries: Number of times to retry for HTTP error 5xx
35 buffersize: Size of download buffer in bytes.
36 noresizebuffer: Do not automatically resize the download buffer.
37 continuedl: Try to continue downloads if possible.
38 noprogress: Do not print the progress bar.
39 logtostderr: Log messages to stderr instead of stdout.
40 consoletitle: Display progress in console window's titlebar.
41 nopart: Do not use temporary .part files.
42 updatetime: Use the Last-modified header to set output file timestamps.
43 test: Download only first bytes to test the downloader.
44 min_filesize: Skip files smaller than this size
45 max_filesize: Skip files larger than this size
46 """
47
48 params = None
49
50 def __init__(self, ydl, params):
51 """Create a FileDownloader object with the given options."""
52 self.ydl = ydl
53 self._progress_hooks = []
54 self.params = params
55
56 @staticmethod
57 def format_seconds(seconds):
58 (mins, secs) = divmod(seconds, 60)
59 (hours, mins) = divmod(mins, 60)
60 if hours > 99:
61 return '--:--:--'
62 if hours == 0:
63 return '%02d:%02d' % (mins, secs)
64 else:
65 return '%02d:%02d:%02d' % (hours, mins, secs)
66
67 @staticmethod
68 def calc_percent(byte_counter, data_len):
69 if data_len is None:
70 return None
71 return float(byte_counter) / float(data_len) * 100.0
72
73 @staticmethod
74 def format_percent(percent):
75 if percent is None:
76 return '---.-%'
77 return '%6s' % ('%3.1f%%' % percent)
78
79 @staticmethod
80 def calc_eta(start, now, total, current):
81 if total is None:
82 return None
83 dif = now - start
84 if current == 0 or dif < 0.001: # One millisecond
85 return None
86 rate = float(current) / dif
87 return int((float(total) - float(current)) / rate)
88
89 @staticmethod
90 def format_eta(eta):
91 if eta is None:
92 return '--:--'
93 return FileDownloader.format_seconds(eta)
94
95 @staticmethod
96 def calc_speed(start, now, bytes):
97 dif = now - start
98 if bytes == 0 or dif < 0.001: # One millisecond
99 return None
100 return float(bytes) / dif
101
102 @staticmethod
103 def format_speed(speed):
104 if speed is None:
105 return '%10s' % '---b/s'
106 return '%10s' % ('%s/s' % format_bytes(speed))
107
108 @staticmethod
109 def best_block_size(elapsed_time, bytes):
110 new_min = max(bytes / 2.0, 1.0)
111 new_max = min(max(bytes * 2.0, 1.0), 4194304) # Do not surpass 4 MB
112 if elapsed_time < 0.001:
113 return int(new_max)
114 rate = bytes / elapsed_time
115 if rate > new_max:
116 return int(new_max)
117 if rate < new_min:
118 return int(new_min)
119 return int(rate)
120
121 @staticmethod
122 def parse_bytes(bytestr):
123 """Parse a string indicating a byte quantity into an integer."""
124 matchobj = re.match(r'(?i)^(\d+(?:\.\d+)?)([kMGTPEZY]?)$', bytestr)
125 if matchobj is None:
126 return None
127 number = float(matchobj.group(1))
128 multiplier = 1024.0 ** 'bkmgtpezy'.index(matchobj.group(2).lower())
129 return int(round(number * multiplier))
130
131 def to_screen(self, *args, **kargs):
132 self.ydl.to_screen(*args, **kargs)
133
134 def to_stderr(self, message):
135 self.ydl.to_screen(message)
136
137 def to_console_title(self, message):
138 self.ydl.to_console_title(message)
139
140 def trouble(self, *args, **kargs):
141 self.ydl.trouble(*args, **kargs)
142
143 def report_warning(self, *args, **kargs):
144 self.ydl.report_warning(*args, **kargs)
145
146 def report_error(self, *args, **kargs):
147 self.ydl.report_error(*args, **kargs)
148
149 def slow_down(self, start_time, byte_counter):
150 """Sleep if the download speed is over the rate limit."""
151 rate_limit = self.params.get('ratelimit', None)
152 if rate_limit is None or byte_counter == 0:
153 return
154 now = time.time()
155 elapsed = now - start_time
156 if elapsed <= 0.0:
157 return
158 speed = float(byte_counter) / elapsed
159 if speed > rate_limit:
160 time.sleep((byte_counter - rate_limit * (now - start_time)) / rate_limit)
161
162 def temp_name(self, filename):
163 """Returns a temporary filename for the given filename."""
164 if self.params.get('nopart', False) or filename == u'-' or \
165 (os.path.exists(encodeFilename(filename)) and not os.path.isfile(encodeFilename(filename))):
166 return filename
167 return filename + u'.part'
168
169 def undo_temp_name(self, filename):
170 if filename.endswith(u'.part'):
171 return filename[:-len(u'.part')]
172 return filename
173
174 def try_rename(self, old_filename, new_filename):
175 try:
176 if old_filename == new_filename:
177 return
178 os.rename(encodeFilename(old_filename), encodeFilename(new_filename))
179 except (IOError, OSError):
180 self.report_error(u'unable to rename file')
181
182 def try_utime(self, filename, last_modified_hdr):
183 """Try to set the last-modified time of the given file."""
184 if last_modified_hdr is None:
185 return
186 if not os.path.isfile(encodeFilename(filename)):
187 return
188 timestr = last_modified_hdr
189 if timestr is None:
190 return
191 filetime = timeconvert(timestr)
192 if filetime is None:
193 return filetime
194 # Ignore obviously invalid dates
195 if filetime == 0:
196 return
197 try:
198 os.utime(filename, (time.time(), filetime))
199 except:
200 pass
201 return filetime
202
203 def report_destination(self, filename):
204 """Report destination filename."""
205 self.to_screen(u'[download] Destination: ' + filename)
206
207 def report_progress(self, percent, data_len_str, speed, eta):
208 """Report download progress."""
209 if self.params.get('noprogress', False):
210 return
211 clear_line = (u'\x1b[K' if sys.stderr.isatty() and os.name != 'nt' else u'')
212 if eta is not None:
213 eta_str = self.format_eta(eta)
214 else:
215 eta_str = 'Unknown ETA'
216 if percent is not None:
217 percent_str = self.format_percent(percent)
218 else:
219 percent_str = 'Unknown %'
220 speed_str = self.format_speed(speed)
221 if self.params.get('progress_with_newline', False):
222 self.to_screen(u'[download] %s of %s at %s ETA %s' %
223 (percent_str, data_len_str, speed_str, eta_str))
224 else:
225 self.to_screen(u'\r%s[download] %s of %s at %s ETA %s' %
226 (clear_line, percent_str, data_len_str, speed_str, eta_str), skip_eol=True)
227 self.to_console_title(u'youtube-dl - %s of %s at %s ETA %s' %
228 (percent_str.strip(), data_len_str.strip(), speed_str.strip(), eta_str.strip()))
229
230 def report_resuming_byte(self, resume_len):
231 """Report attempt to resume at given byte."""
232 self.to_screen(u'[download] Resuming download at byte %s' % resume_len)
233
234 def report_retry(self, count, retries):
235 """Report retry in case of HTTP error 5xx"""
236 self.to_screen(u'[download] Got server HTTP error. Retrying (attempt %d of %d)...' % (count, retries))
237
238 def report_file_already_downloaded(self, file_name):
239 """Report file has already been fully downloaded."""
240 try:
241 self.to_screen(u'[download] %s has already been downloaded' % file_name)
242 except UnicodeEncodeError:
243 self.to_screen(u'[download] The file has already been downloaded')
244
245 def report_unable_to_resume(self):
246 """Report it was impossible to resume download."""
247 self.to_screen(u'[download] Unable to resume')
248
249 def report_finish(self, data_len_str, tot_time):
250 """Report download finished."""
251 if self.params.get('noprogress', False):
252 self.to_screen(u'[download] Download completed')
253 else:
254 clear_line = (u'\x1b[K' if sys.stderr.isatty() and os.name != 'nt' else u'')
255 self.to_screen(u'\r%s[download] 100%% of %s in %s' %
256 (clear_line, data_len_str, self.format_seconds(tot_time)))
257
258 def _download_with_rtmpdump(self, filename, url, player_url, page_url, play_path, tc_url, live):
259 def run_rtmpdump(args):
260 start = time.time()
261 resume_percent = None
262 resume_downloaded_data_len = None
263 proc = subprocess.Popen(args, stderr=subprocess.PIPE)
264 cursor_in_new_line = True
265 proc_stderr_closed = False
266 while not proc_stderr_closed:
267 # read line from stderr
268 line = u''
269 while True:
270 char = proc.stderr.read(1)
271 if not char:
272 proc_stderr_closed = True
273 break
274 if char in [b'\r', b'\n']:
275 break
276 line += char.decode('ascii', 'replace')
277 if not line:
278 # proc_stderr_closed is True
279 continue
280 mobj = re.search(r'([0-9]+\.[0-9]{3}) kB / [0-9]+\.[0-9]{2} sec \(([0-9]{1,2}\.[0-9])%\)', line)
281 if mobj:
282 downloaded_data_len = int(float(mobj.group(1))*1024)
283 percent = float(mobj.group(2))
284 if not resume_percent:
285 resume_percent = percent
286 resume_downloaded_data_len = downloaded_data_len
287 eta = self.calc_eta(start, time.time(), 100-resume_percent, percent-resume_percent)
288 speed = self.calc_speed(start, time.time(), downloaded_data_len-resume_downloaded_data_len)
289 data_len = None
290 if percent > 0:
291 data_len = int(downloaded_data_len * 100 / percent)
292 data_len_str = u'~' + format_bytes(data_len)
293 self.report_progress(percent, data_len_str, speed, eta)
294 cursor_in_new_line = False
295 self._hook_progress({
296 'downloaded_bytes': downloaded_data_len,
297 'total_bytes': data_len,
298 'tmpfilename': tmpfilename,
299 'filename': filename,
300 'status': 'downloading',
301 'eta': eta,
302 'speed': speed,
303 })
304 elif self.params.get('verbose', False):
305 if not cursor_in_new_line:
306 self.to_screen(u'')
307 cursor_in_new_line = True
308 self.to_screen(u'[rtmpdump] '+line)
309 proc.wait()
310 if not cursor_in_new_line:
311 self.to_screen(u'')
312 return proc.returncode
313
314 self.report_destination(filename)
315 tmpfilename = self.temp_name(filename)
316 test = self.params.get('test', False)
317
318 # Check for rtmpdump first
319 try:
320 subprocess.call(['rtmpdump', '-h'], stdout=(open(os.path.devnull, 'w')), stderr=subprocess.STDOUT)
321 except (OSError, IOError):
322 self.report_error(u'RTMP download detected but "rtmpdump" could not be run')
323 return False
324
325 # Download using rtmpdump. rtmpdump returns exit code 2 when
326 # the connection was interrumpted and resuming appears to be
327 # possible. This is part of rtmpdump's normal usage, AFAIK.
328 basic_args = ['rtmpdump', '--verbose', '-r', url, '-o', tmpfilename]
329 if player_url is not None:
330 basic_args += ['--swfVfy', player_url]
331 if page_url is not None:
332 basic_args += ['--pageUrl', page_url]
333 if play_path is not None:
334 basic_args += ['--playpath', play_path]
335 if tc_url is not None:
336 basic_args += ['--tcUrl', url]
337 if test:
338 basic_args += ['--stop', '1']
339 if live:
340 basic_args += ['--live']
341 args = basic_args + [[], ['--resume', '--skip', '1']][self.params.get('continuedl', False)]
342
343 if sys.platform == 'win32' and sys.version_info < (3, 0):
344 # Windows subprocess module does not actually support Unicode
345 # on Python 2.x
346 # See http://stackoverflow.com/a/9951851/35070
347 subprocess_encoding = sys.getfilesystemencoding()
348 args = [a.encode(subprocess_encoding, 'ignore') for a in args]
349 else:
350 subprocess_encoding = None
351
352 if self.params.get('verbose', False):
353 if subprocess_encoding:
354 str_args = [
355 a.decode(subprocess_encoding) if isinstance(a, bytes) else a
356 for a in args]
357 else:
358 str_args = args
359 try:
360 import pipes
361 shell_quote = lambda args: ' '.join(map(pipes.quote, str_args))
362 except ImportError:
363 shell_quote = repr
364 self.to_screen(u'[debug] rtmpdump command line: ' + shell_quote(str_args))
365
366 retval = run_rtmpdump(args)
367
368 while (retval == 2 or retval == 1) and not test:
369 prevsize = os.path.getsize(encodeFilename(tmpfilename))
370 self.to_screen(u'[rtmpdump] %s bytes' % prevsize)
371 time.sleep(5.0) # This seems to be needed
372 retval = run_rtmpdump(basic_args + ['-e'] + [[], ['-k', '1']][retval == 1])
373 cursize = os.path.getsize(encodeFilename(tmpfilename))
374 if prevsize == cursize and retval == 1:
375 break
376 # Some rtmp streams seem abort after ~ 99.8%. Don't complain for those
377 if prevsize == cursize and retval == 2 and cursize > 1024:
378 self.to_screen(u'[rtmpdump] Could not download the whole video. This can happen for some advertisements.')
379 retval = 0
380 break
381 if retval == 0 or (test and retval == 2):
382 fsize = os.path.getsize(encodeFilename(tmpfilename))
383 self.to_screen(u'[rtmpdump] %s bytes' % fsize)
384 self.try_rename(tmpfilename, filename)
385 self._hook_progress({
386 'downloaded_bytes': fsize,
387 'total_bytes': fsize,
388 'filename': filename,
389 'status': 'finished',
390 })
391 return True
392 else:
393 self.to_stderr(u"\n")
394 self.report_error(u'rtmpdump exited with code %d' % retval)
395 return False
396
397 def _download_with_mplayer(self, filename, url):
398 self.report_destination(filename)
399 tmpfilename = self.temp_name(filename)
400
401 args = ['mplayer', '-really-quiet', '-vo', 'null', '-vc', 'dummy', '-dumpstream', '-dumpfile', tmpfilename, url]
402 # Check for mplayer first
403 try:
404 subprocess.call(['mplayer', '-h'], stdout=(open(os.path.devnull, 'w')), stderr=subprocess.STDOUT)
405 except (OSError, IOError):
406 self.report_error(u'MMS or RTSP download detected but "%s" could not be run' % args[0] )
407 return False
408
409 # Download using mplayer.
410 retval = subprocess.call(args)
411 if retval == 0:
412 fsize = os.path.getsize(encodeFilename(tmpfilename))
413 self.to_screen(u'\r[%s] %s bytes' % (args[0], fsize))
414 self.try_rename(tmpfilename, filename)
415 self._hook_progress({
416 'downloaded_bytes': fsize,
417 'total_bytes': fsize,
418 'filename': filename,
419 'status': 'finished',
420 })
421 return True
422 else:
423 self.to_stderr(u"\n")
424 self.report_error(u'mplayer exited with code %d' % retval)
425 return False
426
427 def _download_m3u8_with_ffmpeg(self, filename, url):
428 self.report_destination(filename)
429 tmpfilename = self.temp_name(filename)
430
431 args = ['-y', '-i', url, '-f', 'mp4', '-c', 'copy',
432 '-bsf:a', 'aac_adtstoasc', tmpfilename]
433
434 for program in ['avconv', 'ffmpeg']:
435 try:
436 subprocess.call([program, '-version'], stdout=(open(os.path.devnull, 'w')), stderr=subprocess.STDOUT)
437 break
438 except (OSError, IOError):
439 pass
440 else:
441 self.report_error(u'm3u8 download detected but ffmpeg or avconv could not be found')
442 cmd = [program] + args
443
444 retval = subprocess.call(cmd)
445 if retval == 0:
446 fsize = os.path.getsize(encodeFilename(tmpfilename))
447 self.to_screen(u'\r[%s] %s bytes' % (args[0], fsize))
448 self.try_rename(tmpfilename, filename)
449 self._hook_progress({
450 'downloaded_bytes': fsize,
451 'total_bytes': fsize,
452 'filename': filename,
453 'status': 'finished',
454 })
455 return True
456 else:
457 self.to_stderr(u"\n")
458 self.report_error(u'ffmpeg exited with code %d' % retval)
459 return False
460
461
462 def _do_download(self, filename, info_dict):
463 url = info_dict['url']
464
465 # Check file already present
466 if self.params.get('continuedl', False) and os.path.isfile(encodeFilename(filename)) and not self.params.get('nopart', False):
467 self.report_file_already_downloaded(filename)
468 self._hook_progress({
469 'filename': filename,
470 'status': 'finished',
471 'total_bytes': os.path.getsize(encodeFilename(filename)),
472 })
473 return True
474
475 # Attempt to download using rtmpdump
476 if url.startswith('rtmp'):
477 return self._download_with_rtmpdump(filename, url,
478 info_dict.get('player_url', None),
479 info_dict.get('page_url', None),
480 info_dict.get('play_path', None),
481 info_dict.get('tc_url', None),
482 info_dict.get('rtmp_live', False))
483
484 # Attempt to download using mplayer
485 if url.startswith('mms') or url.startswith('rtsp'):
486 return self._download_with_mplayer(filename, url)
487
488 # m3u8 manifest are downloaded with ffmpeg
489 if determine_ext(url) == u'm3u8':
490 return self._download_m3u8_with_ffmpeg(filename, url)
491
492 tmpfilename = self.temp_name(filename)
493 stream = None
494
495 # Do not include the Accept-Encoding header
496 headers = {'Youtubedl-no-compression': 'True'}
497 if 'user_agent' in info_dict:
498 headers['Youtubedl-user-agent'] = info_dict['user_agent']
499 basic_request = compat_urllib_request.Request(url, None, headers)
500 request = compat_urllib_request.Request(url, None, headers)
501
502 if self.params.get('test', False):
503 request.add_header('Range','bytes=0-10240')
504
505 # Establish possible resume length
506 if os.path.isfile(encodeFilename(tmpfilename)):
507 resume_len = os.path.getsize(encodeFilename(tmpfilename))
508 else:
509 resume_len = 0
510
511 open_mode = 'wb'
512 if resume_len != 0:
513 if self.params.get('continuedl', False):
514 self.report_resuming_byte(resume_len)
515 request.add_header('Range','bytes=%d-' % resume_len)
516 open_mode = 'ab'
517 else:
518 resume_len = 0
519
520 count = 0
521 retries = self.params.get('retries', 0)
522 while count <= retries:
523 # Establish connection
524 try:
525 if count == 0 and 'urlhandle' in info_dict:
526 data = info_dict['urlhandle']
527 data = compat_urllib_request.urlopen(request)
528 break
529 except (compat_urllib_error.HTTPError, ) as err:
530 if (err.code < 500 or err.code >= 600) and err.code != 416:
531 # Unexpected HTTP error
532 raise
533 elif err.code == 416:
534 # Unable to resume (requested range not satisfiable)
535 try:
536 # Open the connection again without the range header
537 data = compat_urllib_request.urlopen(basic_request)
538 content_length = data.info()['Content-Length']
539 except (compat_urllib_error.HTTPError, ) as err:
540 if err.code < 500 or err.code >= 600:
541 raise
542 else:
543 # Examine the reported length
544 if (content_length is not None and
545 (resume_len - 100 < int(content_length) < resume_len + 100)):
546 # The file had already been fully downloaded.
547 # Explanation to the above condition: in issue #175 it was revealed that
548 # YouTube sometimes adds or removes a few bytes from the end of the file,
549 # changing the file size slightly and causing problems for some users. So
550 # I decided to implement a suggested change and consider the file
551 # completely downloaded if the file size differs less than 100 bytes from
552 # the one in the hard drive.
553 self.report_file_already_downloaded(filename)
554 self.try_rename(tmpfilename, filename)
555 self._hook_progress({
556 'filename': filename,
557 'status': 'finished',
558 })
559 return True
560 else:
561 # The length does not match, we start the download over
562 self.report_unable_to_resume()
563 open_mode = 'wb'
564 break
565 # Retry
566 count += 1
567 if count <= retries:
568 self.report_retry(count, retries)
569
570 if count > retries:
571 self.report_error(u'giving up after %s retries' % retries)
572 return False
573
574 data_len = data.info().get('Content-length', None)
575 if data_len is not None:
576 data_len = int(data_len) + resume_len
577 min_data_len = self.params.get("min_filesize", None)
578 max_data_len = self.params.get("max_filesize", None)
579 if min_data_len is not None and data_len < min_data_len:
580 self.to_screen(u'\r[download] File is smaller than min-filesize (%s bytes < %s bytes). Aborting.' % (data_len, min_data_len))
581 return False
582 if max_data_len is not None and data_len > max_data_len:
583 self.to_screen(u'\r[download] File is larger than max-filesize (%s bytes > %s bytes). Aborting.' % (data_len, max_data_len))
584 return False
585
586 data_len_str = format_bytes(data_len)
587 byte_counter = 0 + resume_len
588 block_size = self.params.get('buffersize', 1024)
589 start = time.time()
590 while True:
591 # Download and write
592 before = time.time()
593 data_block = data.read(block_size)
594 after = time.time()
595 if len(data_block) == 0:
596 break
597 byte_counter += len(data_block)
598
599 # Open file just in time
600 if stream is None:
601 try:
602 (stream, tmpfilename) = sanitize_open(tmpfilename, open_mode)
603 assert stream is not None
604 filename = self.undo_temp_name(tmpfilename)
605 self.report_destination(filename)
606 except (OSError, IOError) as err:
607 self.report_error(u'unable to open for writing: %s' % str(err))
608 return False
609 try:
610 stream.write(data_block)
611 except (IOError, OSError) as err:
612 self.to_stderr(u"\n")
613 self.report_error(u'unable to write data: %s' % str(err))
614 return False
615 if not self.params.get('noresizebuffer', False):
616 block_size = self.best_block_size(after - before, len(data_block))
617
618 # Progress message
619 speed = self.calc_speed(start, time.time(), byte_counter - resume_len)
620 if data_len is None:
621 eta = percent = None
622 else:
623 percent = self.calc_percent(byte_counter, data_len)
624 eta = self.calc_eta(start, time.time(), data_len - resume_len, byte_counter - resume_len)
625 self.report_progress(percent, data_len_str, speed, eta)
626
627 self._hook_progress({
628 'downloaded_bytes': byte_counter,
629 'total_bytes': data_len,
630 'tmpfilename': tmpfilename,
631 'filename': filename,
632 'status': 'downloading',
633 'eta': eta,
634 'speed': speed,
635 })
636
637 # Apply rate limit
638 self.slow_down(start, byte_counter - resume_len)
639
640 if stream is None:
641 self.to_stderr(u"\n")
642 self.report_error(u'Did not get any data blocks')
643 return False
644 stream.close()
645 self.report_finish(data_len_str, (time.time() - start))
646 if data_len is not None and byte_counter != data_len:
647 raise ContentTooShortError(byte_counter, int(data_len))
648 self.try_rename(tmpfilename, filename)
649
650 # Update file modification time
651 if self.params.get('updatetime', True):
652 info_dict['filetime'] = self.try_utime(filename, data.info().get('last-modified', None))
653
654 self._hook_progress({
655 'downloaded_bytes': byte_counter,
656 'total_bytes': byte_counter,
657 'filename': filename,
658 'status': 'finished',
659 })
660
661 return True
662
663 def _hook_progress(self, status):
664 for ph in self._progress_hooks:
665 ph(status)
666
667 def add_progress_hook(self, ph):
668 """ ph gets called on download progress, with a dictionary with the entries
669 * filename: The final filename
670 * status: One of "downloading" and "finished"
671
672 It can also have some of the following entries:
673
674 * downloaded_bytes: Bytes on disks
675 * total_bytes: Total bytes, None if unknown
676 * tmpfilename: The filename we're currently writing to
677 * eta: The estimated time in seconds, None if unknown
678 * speed: The download speed in bytes/second, None if unknown
679
680 Hooks are guaranteed to be called at least once (with status "finished")
681 if the download is successful.
682 """
683 self._progress_hooks.append(ph)