youtube_dl/postprocessor/xattrpp.py

   1 from __future__ import unicode_literals
   2
   3 import os
   4 import subprocess
   5 import sys
   6
   7 from .common import PostProcessor
   8 from ..compat import (
   9     subprocess_check_output
  10 )
  11 from ..utils import (
  12     check_executable,
  13     hyphenate_date,
  14     version_tuple,
  15 )
  16
  17
  18 class XAttrMetadataPP(PostProcessor):
  19
  20     #
  21     # More info about extended attributes for media:
  22     #   http://freedesktop.org/wiki/CommonExtendedAttributes/
  23     #   http://www.freedesktop.org/wiki/PhreedomDraft/
  24     #   http://dublincore.org/documents/usageguide/elements.shtml
  25     #
  26     # TODO:
  27     #  * capture youtube keywords and put them in 'user.dublincore.subject' (comma-separated)
  28     #  * figure out which xattrs can be used for 'duration', 'thumbnail', 'resolution'
  29     #
  30
  31     def run(self, info):
  32         """ Set extended attributes on downloaded file (if xattr support is found). """
  33
  34         # This mess below finds the best xattr tool for the job and creates a
  35         # "write_xattr" function.
  36         try:
  37             # try the pyxattr module...
  38             import xattr
  39
  40             # Unicode arguments are not supported in python-pyxattr until
  41             # version 0.5.0
  42             # See https://github.com/rg3/youtube-dl/issues/5498
  43             pyxattr_required_version = '0.5.0'
  44             if version_tuple(xattr.__version__) < version_tuple(pyxattr_required_version):
  45                 self._downloader.report_warning(
  46                     'python-pyxattr is detected but is too old. '
  47                     'youtube-dl requires %s or above while your version is %s. '
  48                     'Falling back to other xattr implementations' % (
  49                         pyxattr_required_version, xattr.__version__))
  50
  51                 raise ImportError
  52
  53             def write_xattr(path, key, value):
  54                 return xattr.setxattr(path, key, value)
  55
  56         except ImportError:
  57             if os.name == 'nt':
  58                 # Write xattrs to NTFS Alternate Data Streams:
  59                 # http://en.wikipedia.org/wiki/NTFS#Alternate_data_streams_.28ADS.29
  60                 def write_xattr(path, key, value):
  61                     assert ':' not in key
  62                     assert os.path.exists(path)
  63
  64                     ads_fn = path + ":" + key
  65                     with open(ads_fn, "wb") as f:
  66                         f.write(value)
  67             else:
  68                 user_has_setfattr = check_executable("setfattr", ['--version'])
  69                 user_has_xattr = check_executable("xattr", ['-h'])
  70
  71                 if user_has_setfattr or user_has_xattr:
  72
  73                     def write_xattr(path, key, value):
  74                         if user_has_setfattr:
  75                             cmd = ['setfattr', '-n', key, '-v', value, path]
  76                         elif user_has_xattr:
  77                             cmd = ['xattr', '-w', key, value, path]
  78
  79                         subprocess_check_output(cmd)
  80
  81                 else:
  82                     # On Unix, and can't find pyxattr, setfattr, or xattr.
  83                     if sys.platform.startswith('linux'):
  84                         self._downloader.report_error(
  85                             "Couldn't find a tool to set the xattrs. "
  86                             "Install either the python 'pyxattr' or 'xattr' "
  87                             "modules, or the GNU 'attr' package "
  88                             "(which contains the 'setfattr' tool).")
  89                     else:
  90                         self._downloader.report_error(
  91                             "Couldn't find a tool to set the xattrs. "
  92                             "Install either the python 'xattr' module, "
  93                             "or the 'xattr' binary.")
  94
  95         # Write the metadata to the file's xattrs
  96         self._downloader.to_screen('[metadata] Writing metadata to file\'s xattrs')
  97
  98         filename = info['filepath']
  99
 100         try:
 101             xattr_mapping = {
 102                 'user.xdg.referrer.url': 'webpage_url',
 103                 # 'user.xdg.comment':            'description',
 104                 'user.dublincore.title': 'title',
 105                 'user.dublincore.date': 'upload_date',
 106                 'user.dublincore.description': 'description',
 107                 'user.dublincore.contributor': 'uploader',
 108                 'user.dublincore.format': 'format',
 109             }
 110
 111             for xattrname, infoname in xattr_mapping.items():
 112
 113                 value = info.get(infoname)
 114
 115                 if value:
 116                     if infoname == "upload_date":
 117                         value = hyphenate_date(value)
 118
 119                     byte_value = value.encode('utf-8')
 120                     write_xattr(filename, xattrname, byte_value)
 121
 122             return [], info
 123
 124         except (subprocess.CalledProcessError, OSError):
 125             self._downloader.report_error("This filesystem doesn't support extended attributes. (You may have to enable them in your /etc/fstab)")
 126             return [], info