mediagoblin/staticdirect.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 ####################################
  18 # Staticdirect infrastructure.
  19 # Borrowed largely from cc.engine
  20 # by Chris Webber & Creative Commons
  21 #
  22 # This needs documentation!
  23 ####################################
  24
  25 import pkg_resources
  26 import logging
  27
  28 _log = logging.getLogger(__name__)
  29
  30
  31 class StaticDirect(object):
  32     def __init__(self):
  33         self.cache = {}
  34
  35     def __call__(self, filepath):
  36         if filepath in self.cache:
  37             return self.cache[filepath]
  38
  39         if not pkg_resources.resource_exists('mediagoblin',
  40                 'static' + filepath):
  41             _log.info("StaticDirect resource %r not found locally",
  42                 filepath)
  43         static_direction = self.cache[filepath] = self.get(filepath)
  44         return static_direction
  45
  46     def get(self, filepath):
  47         # should be implemented by the individual staticdirector
  48         pass
  49
  50
  51 class RemoteStaticDirect(StaticDirect):
  52     def __init__(self, remotepath):
  53         StaticDirect.__init__(self)
  54         self.remotepath = remotepath.rstrip('/')
  55
  56     def get(self, filepath):
  57         return '%s/%s' % (
  58             self.remotepath, filepath.lstrip('/'))
  59
  60
  61 class MultiRemoteStaticDirect(StaticDirect):
  62     """
  63     For whene separate sections of the static data is served under
  64     separate urls.
  65     """
  66     def __init__(self, remotepaths):
  67         StaticDirect.__init__(self)
  68         self.remotepaths = remotepaths
  69
  70     def get(self, filepath):
  71         section, rest = filepath.strip('/').split('/', 1)
  72
  73         return '%s/%s' % (
  74             self.remotepaths[section].rstrip('/'),
  75             rest.lstrip('/'))