mediagoblin/media_types/__init__.py

   1 # GNU MediaGoblin -- federated, autonomous media hosting
   2 # Copyright (C) 2011, 2012 MediaGoblin contributors.  See AUTHORS.
   3 #
   4 # This program is free software: you can redistribute it and/or modify
   5 # it under the terms of the GNU Affero General Public License as published by
   6 # the Free Software Foundation, either version 3 of the License, or
   7 # (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU Affero General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU Affero General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 import os
  18 import sys
  19
  20 from mediagoblin import mg_globals
  21 from mediagoblin.tools.translate import lazy_pass_to_ugettext as _
  22
  23
  24 class FileTypeNotSupported(Exception):
  25     pass
  26
  27 class InvalidFileType(Exception):
  28     pass
  29
  30
  31 def get_media_types():
  32     """
  33     Generator, yields the available media types
  34     """
  35     for media_type in mg_globals.app_config['media_types']:
  36         yield media_type
  37
  38
  39 def get_media_managers():
  40     '''
  41     Generator, yields all enabled media managers
  42     '''
  43     for media_type in get_media_types():
  44         __import__(media_type)
  45
  46         yield media_type, sys.modules[media_type].MEDIA_MANAGER
  47
  48
  49 def get_media_manager(_media_type):
  50     '''
  51     Get the MEDIA_MANAGER based on a media type string
  52
  53     Example::
  54         get_media_type('mediagoblin.media_types.image')
  55     '''
  56     if not _media_type:
  57         return False
  58
  59     for media_type, manager in get_media_managers():
  60         if media_type in _media_type:
  61             return manager
  62
  63     # Nope?  Then raise an error
  64     raise FileTypeNotSupported(
  65         "MediaManager not in enabled types.  Check media_types in config?")
  66
  67
  68 def get_media_type_and_manager(filename):
  69     '''
  70     Get the media type and manager based on a filename
  71     '''
  72     if filename.find('.') > 0:
  73         # Get the file extension
  74         ext = os.path.splitext(filename)[1].lower()
  75     else:
  76         raise InvalidFileType(
  77             _(u'Could not extract any file extension from "{filename}"').format(
  78                 filename=filename))
  79
  80     for media_type, manager in get_media_managers():
  81         # Omit the dot from the extension and match it against
  82         # the media manager
  83         if ext[1:] in manager['accepted_extensions']:
  84             return media_type, manager
  85     else:
  86         raise FileTypeNotSupported(
  87             # TODO: Provide information on which file types are supported
  88             _(u'Sorry, I don\'t support that file type :('))