apps/django_cas/middleware.py

   1 """CAS authentication middleware"""
   2
   3 from urllib import urlencode
   4
   5 from django.http import HttpResponseRedirect, HttpResponseForbidden
   6 from django.conf import settings
   7 from django.contrib.auth import REDIRECT_FIELD_NAME
   8 from django.contrib.auth.views import login, logout
   9 from django.core.urlresolvers import reverse
  10
  11 from django_cas.views import login as cas_login, logout as cas_logout
  12
  13 __all__ = ['CASMiddleware']
  14
  15 class CASMiddleware(object):
  16     """Middleware that allows CAS authentication on admin pages"""
  17
  18     def process_request(self, request):
  19         """Checks that the authentication middleware is installed"""
  20
  21         error = ("The Django CAS middleware requires authentication "
  22                  "middleware to be installed. Edit your MIDDLEWARE_CLASSES "
  23                  "setting to insert 'django.contrib.auth.middleware."
  24                  "AuthenticationMiddleware'.")
  25         assert hasattr(request, 'user'), error
  26
  27     def process_view(self, request, view_func, view_args, view_kwargs):
  28         """Forwards unauthenticated requests to the admin page to the CAS
  29         login URL, as well as calls to django.contrib.auth.views.login and
  30         logout.
  31         """
  32
  33         if view_func == login:
  34             return cas_login(request, *view_args, **view_kwargs)
  35         elif view_func == logout:
  36             return cas_logout(request, *view_args, **view_kwargs)
  37
  38         if settings.CAS_ADMIN_PREFIX:
  39             if not request.path.startswith(settings.CAS_ADMIN_PREFIX):
  40                 return None
  41         elif not view_func.__module__.startswith('django.contrib.admin.'):
  42             return None
  43
  44         if request.user.is_authenticated():
  45             if request.user.is_staff:
  46                 return None
  47             else:
  48                 error = ('<h1>Forbidden</h1><p>You do not have staff '
  49                          'privileges.</p>')
  50                 return HttpResponseForbidden(error)
  51         params = urlencode({REDIRECT_FIELD_NAME: request.get_full_path()})
  52         return HttpResponseRedirect(reverse(cas_login) + '?' + params)