new_contents: #!/usr/bin/python2.5
  #
  # Copyright 2009 the Melange authors.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #   http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  """Middleware to handle exceptions.
  """
  
  __authors__ = [
    '"Sverre Rabbelier" <sverre@rabbelier.nl>',
    ]
  
  
  from google.appengine.runtime.apiproxy_errors import CapabilityDisabledError
  
  from django import http
  from django.utils.translation import ugettext
  
  from soc.views.helper import responses
  
  
  DEF_DOWN_FOR_MAINTENANCE_MSG = ugettext("Down for maintenance")
  DEF_IN_UNEXPECTED_MAINTENANCE_MSG = ugettext(
        "Down for unexpected maintenance.")
  
  
  class MaintenanceMiddleware(object):
    """Middleware to handle maintenance mode.
    """
  
    def maintenance(self, request):
      """Returns a 'down for maintenance' view.
      """
  
      context = responses.getUniversalContext(request)
      context['page_name'] = ugettext('Maintenance')
  
      notice = context.pop('site_notice')
  
      if not notice:
        context['body_content'] = DEF_IN_UNEXPECTED_MAINTENANCE_MSG
      else:
        context['body_content'] = notice
  
      context['header_title'] = DEF_DOWN_FOR_MAINTENANCE_MSG
      context['sidebar_menu_items'] = [
          {'heading': DEF_DOWN_FOR_MAINTENANCE_MSG,
           'group': ''},
          ]
  
      template = 'soc/base.html'
  
      return responses.respond(request, template, context=context)
  
    def process_request(self, request):
      context = responses.getUniversalContext(request)
  
      if not context['is_admin'] and context['in_maintenance']:
        return self.maintenance(request)
  
    def process_exception(self, request, exception):
      if isinstance(exception, CapabilityDisabledError):
        # assume the site is in maintenance if we get CDE
        return maintenance(request)
  
      # let the exception handling middleware handle it
      return None
  
subject: Add MaintenanceMiddleware