X-Git-Url: http://git.ithinksw.org/philo.git/blobdiff_plain/fa49fa4a08db28b3473574fc7a690d87316e9af6..52d3a0f1ca43820d59447c256126aaba7a726dcd:/philo/contrib/shipherd/models.py

diff --git a/philo/contrib/shipherd/models.py b/philo/contrib/shipherd/models.py
index c8579a2..9888378 100644
--- a/philo/contrib/shipherd/models.py
+++ b/philo/contrib/shipherd/models.py
@@ -21,9 +21,15 @@ class NavigationMapper(object, DictMixin):
 	"""
 	def __init__(self, node):
 		self.node = node
+		self._cache = {}
 	
 	def __getitem__(self, key):
-		return Navigation.objects.get_for_node(self.node, key)
+		if key not in self._cache:
+			try:
+				self._cache[key] = Navigation.objects.get_for_node(self.node, key)
+			except Navigation.DoesNotExist:
+				self._cache[key] = None
+		return self._cache[key]
 
 
 def navigation(self):
@@ -42,21 +48,21 @@ class NavigationManager(models.Manager):
 		opts = Node._mptt_meta
 		left = getattr(node, opts.left_attr)
 		right = getattr(node, opts.right_attr)
-		tree = getattr(node, opts.tree_id_attr)
+		tree_id = getattr(node, opts.tree_id_attr)
 		kwargs = {
 			"node__%s__lte" % opts.left_attr: left,
 			"node__%s__gte" % opts.right_attr: right,
 			"node__%s" % opts.tree_id_attr: tree_id
 		}
-		navs = self.filter(key=key, **kwargs).order_by('-node__%s' % opts.level_attr)
+		navs = self.filter(key=key, **kwargs).select_related('node').order_by('-node__%s' % opts.level_attr)
 		nav = navs[0]
-		roots = nav.roots.all()
+		roots = nav.roots.all().select_related('target_node')
 		item_opts = NavigationItem._mptt_meta
 		by_pk = {}
 		tree_ids = []
 		
 		for root in roots:
-			by_pk[root.pk] = pk
+			by_pk[root.pk] = root
 			tree_ids.append(getattr(root, item_opts.tree_id_attr))
 			root._cached_children = []
 		
@@ -65,7 +71,7 @@ class NavigationManager(models.Manager):
 			'%s__lt' % item_opts.level_attr: nav.depth,
 			'%s__gt' % item_opts.level_attr: 0
 		}
-		items = NavigationItem.objects.filter(**kwargs).order_by('level', 'order')
+		items = NavigationItem.objects.filter(**kwargs).select_related('target_node').order_by('level', 'order')
 		for item in items:
 			by_pk[item.pk] = item
 			item._cached_children = []