Added memoization to TargetURLModel.get_target_url.

[philo.git] / philo / models / nodes.py

diff --git a/philo/models/nodes.py b/philo/models/nodes.py
index 7371a1d..58d1b96 100644 (file)
--- a/philo/models/nodes.py
+++ b/philo/models/nodes.py
@@ -335,8 +335,17 @@ class TargetURLModel(models.Model):
                        kwargs = dict([(smart_str(k, 'ascii'), v) for k, v in params.items()])
                return self.url_or_subpath, args, kwargs
        
-       def get_target_url(self):
-               """Calculates and returns the target url based on the :attr:`target_node`, :attr:`url_or_subpath`, and :attr:`reversing_parameters`."""
+       def get_target_url(self, memoize=True):
+               """Calculates and returns the target url based on the :attr:`target_node`, :attr:`url_or_subpath`, and :attr:`reversing_parameters`. The results will be memoized by default; this can be prevented by passing in ``memoize=False``."""
+               if memoize:
+                       memo_args = (self.target_node_id, self.url_or_subpath, self.reversing_parameters_json)
+                       try:
+                               return self._target_url_memo[memo_args]
+                       except AttributeError:
+                               self._target_url_memo = {}
+                       except KeyError:
+                               pass
+               
                node = self.target_node
                if node is not None and node.accepts_subpath and self.url_or_subpath:
                        if self.reversing_parameters is not None:
@@ -346,14 +355,19 @@ class TargetURLModel(models.Model):
                                subpath = self.url_or_subpath
                                if subpath[0] != '/':
                                        subpath = '/' + subpath
-                       return node.construct_url(subpath)
+                       target_url = node.construct_url(subpath)
                elif node is not None:
-                       return node.get_absolute_url()
+                       target_url = node.get_absolute_url()
                else:
                        if self.reversing_parameters is not None:
                                view_name, args, kwargs = self.get_reverse_params()
-                               return reverse(view_name, args=args, kwargs=kwargs)
-                       return self.url_or_subpath
+                               target_url = reverse(view_name, args=args, kwargs=kwargs)
+                       else:
+                               target_url = self.url_or_subpath
+               
+               if memoize:
+                       self._target_url_memo[memo_args] = target_url
+               return target_url
        target_url = property(get_target_url)
        
        class Meta: