Switched nav caching to cache the entire set of nodes for the navigation, not just...

[philo.git] / contrib / navigation / models.py

diff --git a/contrib/navigation/models.py b/contrib/navigation/models.py
index 40f8c07..b37f614 100644 (file)
--- a/contrib/navigation/models.py
+++ b/contrib/navigation/models.py
@@ -2,6 +2,7 @@
 from django.core.exceptions import ValidationError
 from django.core.urlresolvers import NoReverseMatch
 from django.db import models
+from django.forms.models import model_to_dict
 from philo.models import TreeEntity, JSONField, Node, TreeManager
 from philo.validators import RedirectValidator
 
@@ -17,7 +18,7 @@ class NavigationManager(TreeManager):
        # Navigation will probably be used frequently.
        _cache = {}
        
-       def for_node(self, node):
+       def closest_navigation(self, node):
                """
                Returns the set of Navigation objects for a given node's navigation. This
                will be the most recent set of defined hosted navigation among the node's
@@ -55,19 +56,28 @@ class NavigationManager(TreeManager):
                return hosted_navigation
        
        def _add_to_cache(self, using, node, qs=None):
-               if node is None or node.pk is None:
-                       qs = self.none()
-                       key = None
-               else:
-                       key = node.pk
+               key = getattr(node, 'pk', None)
                
                if qs is None:
-                       qs = node.hosted_navigation.select_related('target_node')
+                       if key is None:
+                               roots = self.none()
+                       else:
+                               roots = node.hosted_navigation.select_related('target_node')
+                       
+                       for root in roots:
+                               root_qs = root.get_descendants(include_self=True).complex_filter({'%s__lte' % root._mptt_meta.level_attr: root.get_level() + root.depth}).exclude(depth__isnull=True)
+                               if qs is None:
+                                       qs = root_qs
+                               else:
+                                       qs |= root_qs
+               
+                       if qs is None:
+                               qs = self.none()
                
                self.__class__._cache.setdefault(using, {})[key] = qs
        
        def _get_from_cache(self, using, node):
-               key = node.pk
+               key = getattr(node, 'pk', None)
                return self.__class__._cache[self.db][key]
        
        def _is_cached(self, using, node):
@@ -82,25 +92,17 @@ class NavigationManager(TreeManager):
                Clear out the navigation cache. This needs to happen during database flushes
                or if a navigation entry is changed to prevent caching of outdated navigation information.
                
-               TODO: call this method from update() and delete()!
+               TODO: call this method from update() and delete()! - But how? Those aren't methods available
+               from the manager. The only solution would be to make a special QuerySet subclass that calls
+               this method for each instance.
                """
                if navigation is None:
                        self.__class__._cache.clear()
                else:
                        cache = self.__class__._cache[self.db]
-                       for pk in cache.keys():
-                               for qs in cache[pk]:
-                                       if navigation in qs:
-                                               cache.pop(pk)
-                                               break
-                                       else:
-                                               for instance in qs:
-                                                       if navigation.is_descendant(instance):
-                                                               cache.pop(pk)
-                                                               break
-                                               # necessary?
-                                               if pk not in cache:
-                                                       break
+                       for pk, qs in cache.items():
+                               if navigation in qs:
+                                       cache.pop(pk)
 
 
 class Navigation(TreeEntity):
@@ -116,6 +118,13 @@ class Navigation(TreeEntity):
        order = models.PositiveSmallIntegerField(blank=True, null=True)
        depth = models.PositiveSmallIntegerField(blank=True, null=True, default=DEFAULT_NAVIGATION_DEPTH, help_text="For the root of a hosted tree, defines the depth of the tree. A blank depth will hide this section of navigation. Otherwise, depth is ignored.")
        
+       def __init__(self, *args, **kwargs):
+               super(Navigation, self).__init__(*args, **kwargs)
+               self._initial_data = model_to_dict(self)
+       
+       def __unicode__(self):
+               return self.get_path(field='text', pathsep=u' › ')
+       
        def clean(self):
                # Should this be enforced? Not enforcing it would allow creation of "headers" in the navbar.
                if not self.target_node and not self.url_or_subpath:
@@ -149,10 +158,20 @@ class Navigation(TreeEntity):
                        return self.url_or_subpath
        target_url = property(get_target_url)
        
-       def __unicode__(self):
-               return self.get_path(field='text', pathsep=u' › ')
+       def _has_changed(self):
+               if model_to_dict(self) == self._initial_data:
+                       return False
+               return True
+       
+       def save(self, *args, **kwargs):
+               super(Navigation, self).save(*args, **kwargs)
+               if self._has_changed():
+                       self._initial_data = model_to_dict(self)
+                       Navigation.objects.clear_cache(self)
        
-       # TODO: Add delete and save methods to handle cache clearing.
+       def delete(self, *args, **kwargs):
+               super(Navigation, self).delete(*args, **kwargs)
+               Navigation.objects.clear_cache(self)
        
        class Meta:
                ordering = ['order']