Merged the contribution information from the ithinksw.org philo wiki into the documen...
[philo.git] / philo / middleware.py
index 5ec3e77..f4f7e9d 100644 (file)
@@ -1,57 +1,54 @@
 from django.conf import settings
 from django.contrib.sites.models import Site
 from django.http import Http404
+
 from philo.models import Node, View
+from philo.utils.lazycompat import SimpleLazyObject
 
 
-class LazyNode(object):
-       def __get__(self, request, obj_type=None):
-               if not hasattr(request, '_cached_node_path'):
-                       return None
-               
-               if not hasattr(request, '_found_node'):
-                       try:
-                               current_site = Site.objects.get_current()
-                       except Site.DoesNotExist:
-                               current_site = None
-                       
-                       path = request._cached_node_path
-                       trailing_slash = False
-                       if path[-1] == '/':
-                               trailing_slash = True
-                       
-                       try:
-                               node, subpath = Node.objects.get_with_path(path, root=getattr(current_site, 'root_node', None), absolute_result=False)
-                       except Node.DoesNotExist:
-                               node = None
-                       else:
-                               if subpath is None:
-                                       subpath = ""
-                               subpath = "/" + subpath
-                               
-                               if not node.handles_subpath(subpath):
-                                       node = None
-                               else:
-                                       if trailing_slash and subpath[-1] != "/":
-                                               subpath += "/"
-                                       
-                                       node.subpath = subpath
-                       
-                       request._found_node = node
-               
-               return request._found_node
+def get_node(path):
+       """Returns a :class:`Node` instance at ``path`` (relative to the current site) or ``None``."""
+       try:
+               current_site = Site.objects.get_current()
+       except Site.DoesNotExist:
+               current_site = None
+       
+       trailing_slash = False
+       if path[-1] == '/':
+               trailing_slash = True
+       
+       try:
+               node, subpath = Node.objects.get_with_path(path, root=getattr(current_site, 'root_node', None), absolute_result=False)
+       except Node.DoesNotExist:
+               return None
+       
+       if subpath is None:
+               subpath = ""
+       subpath = "/" + subpath
+       
+       if trailing_slash and subpath[-1] != "/":
+               subpath += "/"
+       
+       node._path = path
+       node._subpath = subpath
+       
+       return node
 
 
 class RequestNodeMiddleware(object):
-       """Middleware to process the request's path and attach the closest ancestor node."""
-       def process_request(self, request):
-               request.__class__.node = LazyNode()
+       """
+       Adds a ``node`` attribute, representing the currently-viewed :class:`.Node`, to every incoming :class:`HttpRequest` object. This is required by :func:`philo.views.node_view`.
        
+       :class:`RequestNodeMiddleware` also catches all exceptions raised while handling requests that have attached :class:`.Node`\ s if :setting:`settings.DEBUG` is ``True``. If a :exc:`django.http.Http404` error was caught, :class:`RequestNodeMiddleware` will look for an "Http404" :class:`.Attribute` on the request's :class:`.Node`; otherwise it will look for an "Http500" :class:`.Attribute`. If an appropriate :class:`.Attribute` is found, and the value of the attribute is a :class:`.View` instance, then the :class:`.View` will be rendered with the exception in the ``extra_context``, bypassing any later handling of exceptions.
+       
+       """
        def process_view(self, request, view_func, view_args, view_kwargs):
                try:
-                       request._cached_node_path = view_kwargs['path']
+                       path = view_kwargs['path']
                except KeyError:
-                       pass
+                       request.node = None
+               else:
+                       request.node = SimpleLazyObject(lambda: get_node(path))
        
        def process_exception(self, request, exception):
                if settings.DEBUG or not hasattr(request, 'node') or not request.node:
@@ -59,12 +56,16 @@ class RequestNodeMiddleware(object):
                
                if isinstance(exception, Http404):
                        error_view = request.node.attributes.get('Http404', None)
+                       status_code = 404
                else:
                        error_view = request.node.attributes.get('Http500', None)
+                       status_code = 500
                
                if error_view is None or not isinstance(error_view, View):
                        # Should this be duck-typing? Perhaps even no testing?
                        return
                
                extra_context = {'exception': exception}
-               return error_view.render_to_response(request, extra_context)
\ No newline at end of file
+               response = error_view.render_to_response(request, extra_context)
+               response.status_code = status_code
+               return response
\ No newline at end of file