Added memoization (optional but enabled by default) to TreeEntity.get_path.

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

diff --git a/philo/models/base.py b/philo/models/base.py
index 0218261..d1dc38a 100644 (file)
--- a/philo/models/base.py
+++ b/philo/models/base.py
@@ -1,7 +1,7 @@
 from django import forms
 from django.contrib.contenttypes.models import ContentType
 from django.contrib.contenttypes import generic
 from django import forms
 from django.contrib.contenttypes.models import ContentType
 from django.contrib.contenttypes import generic

-from django.core.exceptions import ObjectDoesNotExist
+from django.core.exceptions import ValidationError

 from django.core.validators import RegexValidator
 from django.db import models
 from django.utils import simplejson as json
 from django.core.validators import RegexValidator
 from django.db import models
 from django.utils import simplejson as json


@@ -16,7 +16,7 @@ from philo.utils.entities import AttributeMapper, TreeAttributeMapper
 from philo.validators import json_validator
 
 
 from philo.validators import json_validator
 
 

-__all__ = ('Tag', 'value_content_type_limiter', 'register_value_model', 'unregister_value_model', 'JSONValue', 'ForeignKeyValue', 'ManyToManyValue', 'Attribute', 'Entity', 'TreeEntity')
+__all__ = ('Tag', 'value_content_type_limiter', 'register_value_model', 'unregister_value_model', 'JSONValue', 'ForeignKeyValue', 'ManyToManyValue', 'Attribute', 'Entity', 'TreeEntity', 'SlugTreeEntity')

 
 
 class Tag(models.Model):
 
 
 class Tag(models.Model):


@@ -319,7 +319,12 @@ class Entity(models.Model):
                
                """
                return mapper(self)
                
                """
                return mapper(self)

-       attributes = property(get_attribute_mapper)
+       
+       @property
+       def attributes(self):
+               if not hasattr(self, '_attributes'):
+                       self._attributes = self.get_attribute_mapper()
+               return self._attributes

        
        class Meta:
                abstract = True
        
        class Meta:
                abstract = True


@@ -453,11 +458,12 @@ class TreeEntity(Entity, MPTTModel):
        objects = TreeEntityManager()
        parent = models.ForeignKey('self', related_name='children', null=True, blank=True)
        
        objects = TreeEntityManager()
        parent = models.ForeignKey('self', related_name='children', null=True, blank=True)
        

-       def get_path(self, root=None, pathsep='/', field='slug'):
+       def get_path(self, root=None, pathsep='/', field='pk', memoize=True):

                """
                :param root: Only return the path since this object.
                :param pathsep: The path separator to use when constructing an instance's path
                :param field: The field to pull path information from for each ancestor.
                """
                :param root: Only return the path since this object.
                :param pathsep: The path separator to use when constructing an instance's path
                :param field: The field to pull path information from for each ancestor.

+               :param memoize: Whether to use memoized results. Since, in most cases, the ancestors of a TreeEntity will not change over the course of an instance's lifetime, this defaults to ``True``.

                :returns: A string representation of an object's path.
                
                """
                :returns: A string representation of an object's path.
                
                """


@@ -471,12 +477,26 @@ class TreeEntity(Entity, MPTTModel):
                if root is not None and not self.is_descendant_of(root):
                        raise AncestorDoesNotExist(root)
                
                if root is not None and not self.is_descendant_of(root):
                        raise AncestorDoesNotExist(root)
                

+               if memoize:
+                       memo_args = (getattr(self, "%s_id" % self._mptt_meta.parent_attr), getattr(root, 'pk', None), pathsep, getattr(self, field, '?'))
+                       try:
+                               return self._path_memo[memo_args]
+                       except AttributeError:
+                               self._path_memo = {}
+                       except KeyError:
+                               pass
+               

                qs = self.get_ancestors(include_self=True)
                
                if root is not None:
                        qs = qs.filter(**{'%s__gt' % self._mptt_meta.level_attr: root.get_level()})
                
                qs = self.get_ancestors(include_self=True)
                
                if root is not None:
                        qs = qs.filter(**{'%s__gt' % self._mptt_meta.level_attr: root.get_level()})
                

-               return pathsep.join([getattr(parent, field, '?') for parent in qs])
+               path = pathsep.join([getattr(parent, field, '?') for parent in qs])
+               
+               if memoize:
+                       self._path_memo[memo_args] = path
+               
+               return path

        path = property(get_path)
        
        def get_attribute_mapper(self, mapper=None):
        path = property(get_path)
        
        def get_attribute_mapper(self, mapper=None):


@@ -500,7 +520,6 @@ class TreeEntity(Entity, MPTTModel):
                        else:
                                mapper = AttributeMapper
                return super(TreeEntity, self).get_attribute_mapper(mapper)
                        else:
                                mapper = AttributeMapper
                return super(TreeEntity, self).get_attribute_mapper(mapper)

-       attributes = property(get_attribute_mapper)

        
        def __unicode__(self):
                return self.path
        
        def __unicode__(self):
                return self.path


@@ -518,10 +537,19 @@ class SlugTreeEntity(TreeEntity):
        objects = SlugTreeEntityManager()
        slug = models.SlugField(max_length=255)
        
        objects = SlugTreeEntityManager()
        slug = models.SlugField(max_length=255)
        

-       def get_path(self, root=None, pathsep='/', field='slug'):
-               return super(SlugTreeEntity, self).get_path(root, pathsep, field)
+       def get_path(self, root=None, pathsep='/', field='slug', memoize=True):
+               return super(SlugTreeEntity, self).get_path(root, pathsep, field, memoize)

        path = property(get_path)
        
        path = property(get_path)
        

+       def clean(self):
+               if self.parent is None:
+                       try:
+                               self._default_manager.exclude(pk=self.pk).get(slug=self.slug, parent__isnull=True)
+                       except self.DoesNotExist:
+                               pass
+                       else:
+                               raise ValidationError(self.unique_error_message(self.__class__, ('parent', 'slug')))
+       

        class Meta:
                unique_together = ('parent', 'slug')
                abstract = True
\ No newline at end of file
        class Meta:
                unique_together = ('parent', 'slug')
                abstract = True
\ No newline at end of file