youtube_dlc/postprocessor/common.py

   1 from __future__ import unicode_literals
   2
   3 import os
   4
   5 from ..compat import compat_str
   6 from ..utils import (
   7     cli_configuration_args,
   8     encodeFilename,
   9     PostProcessingError,
  10 )
  11
  12
  13 class PostProcessor(object):
  14     """Post Processor class.
  15
  16     PostProcessor objects can be added to downloaders with their
  17     add_post_processor() method. When the downloader has finished a
  18     successful download, it will take its internal chain of PostProcessors
  19     and start calling the run() method on each one of them, first with
  20     an initial argument and then with the returned value of the previous
  21     PostProcessor.
  22
  23     The chain will be stopped if one of them ever returns None or the end
  24     of the chain is reached.
  25
  26     PostProcessor objects follow a "mutual registration" process similar
  27     to InfoExtractor objects.
  28
  29     Optionally PostProcessor can use a list of additional command-line arguments
  30     with self._configuration_args.
  31     """
  32
  33     _downloader = None
  34
  35     def __init__(self, downloader=None):
  36         self._downloader = downloader
  37         self.PP_NAME = self.pp_key()
  38
  39     @classmethod
  40     def pp_key(cls):
  41         name = cls.__name__[:-2]
  42         return compat_str(name[6:]) if name[:6].lower() == 'ffmpeg' else name
  43
  44     def to_screen(self, text, prefix=True, *args, **kwargs):
  45         tag = '[%s] ' % self.PP_NAME if prefix else ''
  46         if self._downloader:
  47             return self._downloader.to_screen('%s%s' % (tag, text), *args, **kwargs)
  48
  49     def report_warning(self, text, *args, **kwargs):
  50         if self._downloader:
  51             return self._downloader.report_warning(text, *args, **kwargs)
  52
  53     def report_error(self, text, *args, **kwargs):
  54         if self._downloader:
  55             return self._downloader.report_error(text, *args, **kwargs)
  56
  57     def write_debug(self, text, prefix=True, *args, **kwargs):
  58         tag = '[debug] ' if prefix else ''
  59         if self.get_param('verbose', False) and self._downloader:
  60             return self._downloader.to_screen('%s%s' % (tag, text), *args, **kwargs)
  61
  62     def get_param(self, name, default=None, *args, **kwargs):
  63         if self._downloader:
  64             return self._downloader.params.get(name, default, *args, **kwargs)
  65         return default
  66
  67     def set_downloader(self, downloader):
  68         """Sets the downloader for this PP."""
  69         self._downloader = downloader
  70
  71     def run(self, information):
  72         """Run the PostProcessor.
  73
  74         The "information" argument is a dictionary like the ones
  75         composed by InfoExtractors. The only difference is that this
  76         one has an extra field called "filepath" that points to the
  77         downloaded file.
  78
  79         This method returns a tuple, the first element is a list of the files
  80         that can be deleted, and the second of which is the updated
  81         information.
  82
  83         In addition, this method may raise a PostProcessingError
  84         exception if post processing fails.
  85         """
  86         return [], information  # by default, keep file and do nothing
  87
  88     def try_utime(self, path, atime, mtime, errnote='Cannot update utime of file'):
  89         try:
  90             os.utime(encodeFilename(path), (atime, mtime))
  91         except Exception:
  92             self.report_warning(errnote)
  93
  94     def _configuration_args(self, default=[], exe=None):
  95         key = self.pp_key().lower()
  96         args, is_compat = cli_configuration_args(
  97             self._downloader.params, 'postprocessor_args', key, default, exe)
  98         return args if not is_compat or key != 'sponskrub' else default
  99
 100
 101 class AudioConversionError(PostProcessingError):
 102     pass