+# the following line enables the selection of a node as the root for a given django.contrib.sites Site object
+models.ForeignKey(Node, related_name='sites', null=True, blank=True).contribute_to_class(Site, 'root_node')
+
+
+class View(Entity):
+ nodes = generic.GenericRelation(Node, content_type_field='view_content_type', object_id_field='view_object_id')
+
+ accepts_subpath = False
+
+ def get_subpath(self, obj):
+ if not self.accepts_subpath:
+ raise ViewDoesNotProvideSubpaths
+
+ view_name, args, kwargs = self.get_reverse_params(obj)
+ try:
+ return reverse(view_name, args=args, kwargs=kwargs, urlconf=self)
+ except NoReverseMatch:
+ raise ViewCanNotProvideSubpath
+
+ def get_reverse_params(self, obj):
+ """This method should return a view_name, args, kwargs tuple suitable for reversing a url for the given obj using self as the urlconf."""
+ raise NotImplementedError("View subclasses must implement get_reverse_params to support subpaths.")
+
+ def attributes_with_node(self, node):
+ return QuerySetMapper(self.attribute_set, passthrough=node.attributes)
+
+ def render_to_response(self, request, extra_context=None):
+ if not hasattr(request, 'node'):
+ raise MIDDLEWARE_NOT_CONFIGURED
+
+ extra_context = extra_context or {}
+ view_about_to_render.send(sender=self, request=request, extra_context=extra_context)
+ response = self.actually_render_to_response(request, extra_context)
+ view_finished_rendering.send(sender=self, response=response)
+ return response
+
+ def actually_render_to_response(self, request, extra_context=None):
+ raise NotImplementedError('View subclasses must implement render_to_response.')
+
+ class Meta:
+ abstract = True
+
+
+_view_content_type_limiter.cls = View
+
+
+class MultiView(View):