[http] Rework HTTP downloader
* Simplify code and split into separate routines to facilitate maintaining * Make retry mechanism work on errors during actual download not only during connection establishment phase * Retry on ECONNRESET and ETIMEDOUT during reading data from network * Retry on content too short and various timeout errors * Show error description on retry * Closes #506, closes #809, closes #2849, closes #4240, closes #6023, closes #8625, closes #9483
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		| @@ -304,11 +304,11 @@ class FileDownloader(object): | ||||
|         """Report attempt to resume at given byte.""" | ||||
|         self.to_screen('[download] Resuming download at byte %s' % resume_len) | ||||
|  | ||||
|     def report_retry(self, count, retries): | ||||
|     def report_retry(self, err, count, retries): | ||||
|         """Report retry in case of HTTP error 5xx""" | ||||
|         self.to_screen( | ||||
|             '[download] Got server HTTP error. Retrying (attempt %d of %s)...' | ||||
|             % (count, self.format_retries(retries))) | ||||
|             '[download] Got server HTTP error: %s. Retrying (attempt %d of %s)...' | ||||
|             % (error_to_compat_str(err), count, self.format_retries(retries))) | ||||
|  | ||||
|     def report_file_already_downloaded(self, file_name): | ||||
|         """Report file has already been fully downloaded.""" | ||||
|   | ||||
| @@ -22,8 +22,16 @@ from ..utils import ( | ||||
| class HttpFD(FileDownloader): | ||||
|     def real_download(self, filename, info_dict): | ||||
|         url = info_dict['url'] | ||||
|         tmpfilename = self.temp_name(filename) | ||||
|         stream = None | ||||
|  | ||||
|         class DownloadContext(dict): | ||||
|             __getattr__ = dict.get | ||||
|             __setattr__ = dict.__setitem__ | ||||
|             __delattr__ = dict.__delitem__ | ||||
|  | ||||
|         ctx = DownloadContext() | ||||
|         ctx.filename = filename | ||||
|         ctx.tmpfilename = self.temp_name(filename) | ||||
|         ctx.stream = None | ||||
|  | ||||
|         # Do not include the Accept-Encoding header | ||||
|         headers = {'Youtubedl-no-compression': 'True'} | ||||
| @@ -38,46 +46,51 @@ class HttpFD(FileDownloader): | ||||
|         if is_test: | ||||
|             request.add_header('Range', 'bytes=0-%s' % str(self._TEST_FILE_SIZE - 1)) | ||||
|  | ||||
|         # Establish possible resume length | ||||
|         if os.path.isfile(encodeFilename(tmpfilename)): | ||||
|             resume_len = os.path.getsize(encodeFilename(tmpfilename)) | ||||
|         else: | ||||
|             resume_len = 0 | ||||
|         ctx.open_mode = 'wb' | ||||
|         ctx.resume_len = 0 | ||||
|  | ||||
|         open_mode = 'wb' | ||||
|         if resume_len != 0: | ||||
|             if self.params.get('continuedl', True): | ||||
|                 self.report_resuming_byte(resume_len) | ||||
|                 request.add_header('Range', 'bytes=%d-' % resume_len) | ||||
|                 open_mode = 'ab' | ||||
|             else: | ||||
|                 resume_len = 0 | ||||
|         if self.params.get('continuedl', True): | ||||
|             # Establish possible resume length | ||||
|             if os.path.isfile(encodeFilename(ctx.tmpfilename)): | ||||
|                 ctx.resume_len = os.path.getsize(encodeFilename(ctx.tmpfilename)) | ||||
|  | ||||
|         count = 0 | ||||
|         retries = self.params.get('retries', 0) | ||||
|         while count <= retries: | ||||
|  | ||||
|         class SucceedDownload(Exception): | ||||
|             pass | ||||
|  | ||||
|         class RetryDownload(Exception): | ||||
|             def __init__(self, source_error): | ||||
|                 self.source_error = source_error | ||||
|  | ||||
|         def establish_connection(): | ||||
|             if ctx.resume_len != 0: | ||||
|                 self.report_resuming_byte(ctx.resume_len) | ||||
|                 request.add_header('Range', 'bytes=%d-' % ctx.resume_len) | ||||
|                 ctx.open_mode = 'ab' | ||||
|             # Establish connection | ||||
|             try: | ||||
|                 data = self.ydl.urlopen(request) | ||||
|                 ctx.data = self.ydl.urlopen(request) | ||||
|                 # When trying to resume, Content-Range HTTP header of response has to be checked | ||||
|                 # to match the value of requested Range HTTP header. This is due to a webservers | ||||
|                 # that don't support resuming and serve a whole file with no Content-Range | ||||
|                 # set in response despite of requested Range (see | ||||
|                 # https://github.com/rg3/youtube-dl/issues/6057#issuecomment-126129799) | ||||
|                 if resume_len > 0: | ||||
|                     content_range = data.headers.get('Content-Range') | ||||
|                 if ctx.resume_len > 0: | ||||
|                     content_range = ctx.data.headers.get('Content-Range') | ||||
|                     if content_range: | ||||
|                         content_range_m = re.search(r'bytes (\d+)-', content_range) | ||||
|                         # Content-Range is present and matches requested Range, resume is possible | ||||
|                         if content_range_m and resume_len == int(content_range_m.group(1)): | ||||
|                             break | ||||
|                         if content_range_m and ctx.resume_len == int(content_range_m.group(1)): | ||||
|                             return | ||||
|                     # Content-Range is either not present or invalid. Assuming remote webserver is | ||||
|                     # trying to send the whole file, resume is not possible, so wiping the local file | ||||
|                     # and performing entire redownload | ||||
|                     self.report_unable_to_resume() | ||||
|                     resume_len = 0 | ||||
|                     open_mode = 'wb' | ||||
|                 break | ||||
|                     ctx.resume_len = 0 | ||||
|                     ctx.open_mode = 'wb' | ||||
|                 return | ||||
|             except (compat_urllib_error.HTTPError, ) as err: | ||||
|                 if (err.code < 500 or err.code >= 600) and err.code != 416: | ||||
|                     # Unexpected HTTP error | ||||
| @@ -86,15 +99,15 @@ class HttpFD(FileDownloader): | ||||
|                     # Unable to resume (requested range not satisfiable) | ||||
|                     try: | ||||
|                         # Open the connection again without the range header | ||||
|                         data = self.ydl.urlopen(basic_request) | ||||
|                         content_length = data.info()['Content-Length'] | ||||
|                         ctx.data = self.ydl.urlopen(basic_request) | ||||
|                         content_length = ctx.data.info()['Content-Length'] | ||||
|                     except (compat_urllib_error.HTTPError, ) as err: | ||||
|                         if err.code < 500 or err.code >= 600: | ||||
|                             raise | ||||
|                     else: | ||||
|                         # Examine the reported length | ||||
|                         if (content_length is not None and | ||||
|                                 (resume_len - 100 < int(content_length) < resume_len + 100)): | ||||
|                                 (ctx.resume_len - 100 < int(content_length) < ctx.resume_len + 100)): | ||||
|                             # The file had already been fully downloaded. | ||||
|                             # Explanation to the above condition: in issue #175 it was revealed that | ||||
|                             # YouTube sometimes adds or removes a few bytes from the end of the file, | ||||
| @@ -102,152 +115,184 @@ class HttpFD(FileDownloader): | ||||
|                             # I decided to implement a suggested change and consider the file | ||||
|                             # completely downloaded if the file size differs less than 100 bytes from | ||||
|                             # the one in the hard drive. | ||||
|                             self.report_file_already_downloaded(filename) | ||||
|                             self.try_rename(tmpfilename, filename) | ||||
|                             self.report_file_already_downloaded(ctx.filename) | ||||
|                             self.try_rename(ctx.tmpfilename, ctx.filename) | ||||
|                             self._hook_progress({ | ||||
|                                 'filename': filename, | ||||
|                                 'filename': ctx.filename, | ||||
|                                 'status': 'finished', | ||||
|                                 'downloaded_bytes': resume_len, | ||||
|                                 'total_bytes': resume_len, | ||||
|                                 'downloaded_bytes': ctx.resume_len, | ||||
|                                 'total_bytes': ctx.resume_len, | ||||
|                             }) | ||||
|                             return True | ||||
|                             raise SucceedDownload() | ||||
|                         else: | ||||
|                             # The length does not match, we start the download over | ||||
|                             self.report_unable_to_resume() | ||||
|                             resume_len = 0 | ||||
|                             open_mode = 'wb' | ||||
|                             break | ||||
|             except socket.error as e: | ||||
|                 if e.errno != errno.ECONNRESET: | ||||
|                             ctx.resume_len = 0 | ||||
|                             ctx.open_mode = 'wb' | ||||
|                             return | ||||
|                 raise RetryDownload(err) | ||||
|             except socket.error as err: | ||||
|                 if err.errno != errno.ECONNRESET: | ||||
|                     # Connection reset is no problem, just retry | ||||
|                     raise | ||||
|                 raise RetryDownload(err) | ||||
|  | ||||
|             # Retry | ||||
|             count += 1 | ||||
|             if count <= retries: | ||||
|                 self.report_retry(count, retries) | ||||
|         def download(): | ||||
|             data_len = ctx.data.info().get('Content-length', None) | ||||
|  | ||||
|         if count > retries: | ||||
|             self.report_error('giving up after %s retries' % retries) | ||||
|             return False | ||||
|             # Range HTTP header may be ignored/unsupported by a webserver | ||||
|             # (e.g. extractor/scivee.py, extractor/bambuser.py). | ||||
|             # However, for a test we still would like to download just a piece of a file. | ||||
|             # To achieve this we limit data_len to _TEST_FILE_SIZE and manually control | ||||
|             # block size when downloading a file. | ||||
|             if is_test and (data_len is None or int(data_len) > self._TEST_FILE_SIZE): | ||||
|                 data_len = self._TEST_FILE_SIZE | ||||
|  | ||||
|         data_len = data.info().get('Content-length', None) | ||||
|  | ||||
|         # Range HTTP header may be ignored/unsupported by a webserver | ||||
|         # (e.g. extractor/scivee.py, extractor/bambuser.py). | ||||
|         # However, for a test we still would like to download just a piece of a file. | ||||
|         # To achieve this we limit data_len to _TEST_FILE_SIZE and manually control | ||||
|         # block size when downloading a file. | ||||
|         if is_test and (data_len is None or int(data_len) > self._TEST_FILE_SIZE): | ||||
|             data_len = self._TEST_FILE_SIZE | ||||
|  | ||||
|         if data_len is not None: | ||||
|             data_len = int(data_len) + resume_len | ||||
|             min_data_len = self.params.get('min_filesize') | ||||
|             max_data_len = self.params.get('max_filesize') | ||||
|             if min_data_len is not None and data_len < min_data_len: | ||||
|                 self.to_screen('\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('\r[download] File is larger than max-filesize (%s bytes > %s bytes). Aborting.' % (data_len, max_data_len)) | ||||
|                 return False | ||||
|  | ||||
|         byte_counter = 0 + resume_len | ||||
|         block_size = self.params.get('buffersize', 1024) | ||||
|         start = time.time() | ||||
|  | ||||
|         # measure time over whole while-loop, so slow_down() and best_block_size() work together properly | ||||
|         now = None  # needed for slow_down() in the first loop run | ||||
|         before = start  # start measuring | ||||
|         while True: | ||||
|  | ||||
|             # Download and write | ||||
|             data_block = data.read(block_size if not is_test else min(block_size, data_len - byte_counter)) | ||||
|             byte_counter += len(data_block) | ||||
|  | ||||
|             # exit loop when download is finished | ||||
|             if len(data_block) == 0: | ||||
|                 break | ||||
|  | ||||
|             # Open destination 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('unable to open for writing: %s' % str(err)) | ||||
|             if data_len is not None: | ||||
|                 data_len = int(data_len) + ctx.resume_len | ||||
|                 min_data_len = self.params.get('min_filesize') | ||||
|                 max_data_len = self.params.get('max_filesize') | ||||
|                 if min_data_len is not None and data_len < min_data_len: | ||||
|                     self.to_screen('\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('\r[download] File is larger than max-filesize (%s bytes > %s bytes). Aborting.' % (data_len, max_data_len)) | ||||
|                     return False | ||||
|  | ||||
|                 if self.params.get('xattr_set_filesize', False) and data_len is not None: | ||||
|             byte_counter = 0 + ctx.resume_len | ||||
|             block_size = self.params.get('buffersize', 1024) | ||||
|             start = time.time() | ||||
|  | ||||
|             # measure time over whole while-loop, so slow_down() and best_block_size() work together properly | ||||
|             now = None  # needed for slow_down() in the first loop run | ||||
|             before = start  # start measuring | ||||
|  | ||||
|             def retry(e): | ||||
|                 if ctx.tmpfilename != '-': | ||||
|                     ctx.stream.close() | ||||
|                 ctx.stream = None | ||||
|                 ctx.resume_len = os.path.getsize(encodeFilename(ctx.tmpfilename)) | ||||
|                 raise RetryDownload(e) | ||||
|  | ||||
|             while True: | ||||
|                 try: | ||||
|                     # Download and write | ||||
|                     data_block = ctx.data.read(block_size if not is_test else min(block_size, data_len - byte_counter)) | ||||
|                 # socket.timeout is a subclass of socket.error but may not have | ||||
|                 # errno set | ||||
|                 except socket.timeout as e: | ||||
|                     retry(e) | ||||
|                 except socket.error as e: | ||||
|                     if e.errno not in (errno.ECONNRESET, errno.ETIMEDOUT): | ||||
|                         raise | ||||
|                     retry(e) | ||||
|  | ||||
|                 byte_counter += len(data_block) | ||||
|  | ||||
|                 # exit loop when download is finished | ||||
|                 if len(data_block) == 0: | ||||
|                     break | ||||
|  | ||||
|                 # Open destination file just in time | ||||
|                 if ctx.stream is None: | ||||
|                     try: | ||||
|                         write_xattr(tmpfilename, 'user.ytdl.filesize', str(data_len).encode('utf-8')) | ||||
|                     except (XAttrUnavailableError, XAttrMetadataError) as err: | ||||
|                         self.report_error('unable to set filesize xattr: %s' % str(err)) | ||||
|                         ctx.stream, ctx.tmpfilename = sanitize_open( | ||||
|                             ctx.tmpfilename, ctx.open_mode) | ||||
|                         assert ctx.stream is not None | ||||
|                         ctx.filename = self.undo_temp_name(ctx.tmpfilename) | ||||
|                         self.report_destination(ctx.filename) | ||||
|                     except (OSError, IOError) as err: | ||||
|                         self.report_error('unable to open for writing: %s' % str(err)) | ||||
|                         return False | ||||
|  | ||||
|             try: | ||||
|                 stream.write(data_block) | ||||
|             except (IOError, OSError) as err: | ||||
|                     if self.params.get('xattr_set_filesize', False) and data_len is not None: | ||||
|                         try: | ||||
|                             write_xattr(ctx.tmpfilename, 'user.ytdl.filesize', str(data_len).encode('utf-8')) | ||||
|                         except (XAttrUnavailableError, XAttrMetadataError) as err: | ||||
|                             self.report_error('unable to set filesize xattr: %s' % str(err)) | ||||
|  | ||||
|                 try: | ||||
|                     ctx.stream.write(data_block) | ||||
|                 except (IOError, OSError) as err: | ||||
|                     self.to_stderr('\n') | ||||
|                     self.report_error('unable to write data: %s' % str(err)) | ||||
|                     return False | ||||
|  | ||||
|                 # Apply rate limit | ||||
|                 self.slow_down(start, now, byte_counter - ctx.resume_len) | ||||
|  | ||||
|                 # end measuring of one loop run | ||||
|                 now = time.time() | ||||
|                 after = now | ||||
|  | ||||
|                 # Adjust block size | ||||
|                 if not self.params.get('noresizebuffer', False): | ||||
|                     block_size = self.best_block_size(after - before, len(data_block)) | ||||
|  | ||||
|                 before = after | ||||
|  | ||||
|                 # Progress message | ||||
|                 speed = self.calc_speed(start, now, byte_counter - ctx.resume_len) | ||||
|                 if data_len is None: | ||||
|                     eta = None | ||||
|                 else: | ||||
|                     eta = self.calc_eta(start, time.time(), data_len - ctx.resume_len, byte_counter - ctx.resume_len) | ||||
|  | ||||
|                 self._hook_progress({ | ||||
|                     'status': 'downloading', | ||||
|                     'downloaded_bytes': byte_counter, | ||||
|                     'total_bytes': data_len, | ||||
|                     'tmpfilename': ctx.tmpfilename, | ||||
|                     'filename': ctx.filename, | ||||
|                     'eta': eta, | ||||
|                     'speed': speed, | ||||
|                     'elapsed': now - start, | ||||
|                 }) | ||||
|  | ||||
|                 if is_test and byte_counter == data_len: | ||||
|                     break | ||||
|  | ||||
|             if ctx.stream is None: | ||||
|                 self.to_stderr('\n') | ||||
|                 self.report_error('unable to write data: %s' % str(err)) | ||||
|                 self.report_error('Did not get any data blocks') | ||||
|                 return False | ||||
|             if ctx.tmpfilename != '-': | ||||
|                 ctx.stream.close() | ||||
|  | ||||
|             # Apply rate limit | ||||
|             self.slow_down(start, now, byte_counter - resume_len) | ||||
|             if data_len is not None and byte_counter != data_len: | ||||
|                 err = ContentTooShortError(byte_counter, int(data_len)) | ||||
|                 if count <= retries: | ||||
|                     retry(err) | ||||
|                 raise err | ||||
|  | ||||
|             # end measuring of one loop run | ||||
|             now = time.time() | ||||
|             after = now | ||||
|             self.try_rename(ctx.tmpfilename, ctx.filename) | ||||
|  | ||||
|             # Adjust block size | ||||
|             if not self.params.get('noresizebuffer', False): | ||||
|                 block_size = self.best_block_size(after - before, len(data_block)) | ||||
|  | ||||
|             before = after | ||||
|  | ||||
|             # Progress message | ||||
|             speed = self.calc_speed(start, now, byte_counter - resume_len) | ||||
|             if data_len is None: | ||||
|                 eta = None | ||||
|             else: | ||||
|                 eta = self.calc_eta(start, time.time(), data_len - resume_len, byte_counter - resume_len) | ||||
|             # Update file modification time | ||||
|             if self.params.get('updatetime', True): | ||||
|                 info_dict['filetime'] = self.try_utime(ctx.filename, ctx.data.info().get('last-modified', None)) | ||||
|  | ||||
|             self._hook_progress({ | ||||
|                 'status': 'downloading', | ||||
|                 'downloaded_bytes': byte_counter, | ||||
|                 'total_bytes': data_len, | ||||
|                 'tmpfilename': tmpfilename, | ||||
|                 'filename': filename, | ||||
|                 'eta': eta, | ||||
|                 'speed': speed, | ||||
|                 'elapsed': now - start, | ||||
|                 'total_bytes': byte_counter, | ||||
|                 'filename': ctx.filename, | ||||
|                 'status': 'finished', | ||||
|                 'elapsed': time.time() - start, | ||||
|             }) | ||||
|  | ||||
|             if is_test and byte_counter == data_len: | ||||
|                 break | ||||
|             return True | ||||
|  | ||||
|         if stream is None: | ||||
|             self.to_stderr('\n') | ||||
|             self.report_error('Did not get any data blocks') | ||||
|             return False | ||||
|         if tmpfilename != '-': | ||||
|             stream.close() | ||||
|         while count <= retries: | ||||
|             try: | ||||
|                 establish_connection() | ||||
|                 download() | ||||
|                 return True | ||||
|             except RetryDownload as e: | ||||
|                 count += 1 | ||||
|                 if count <= retries: | ||||
|                     self.report_retry(e.source_error, count, retries) | ||||
|                 continue | ||||
|             except SucceedDownload: | ||||
|                 return True | ||||
|  | ||||
|         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', | ||||
|             'elapsed': time.time() - start, | ||||
|         }) | ||||
|  | ||||
|         return True | ||||
|         self.report_error('giving up after %s retries' % retries) | ||||
|         return False | ||||
|   | ||||
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	 Sergey M․
					Sergey M․