Fixed #7052 -- Added support for natural keys in serialization.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@11863 bcc190cf-cafb-0310-a4f2-bffc1f526a37

2 files changed, 22 insertions, 0 deletions

diff --git a/django/contrib/auth/models.py b/django/contrib/auth/models.py
index 053761cb56..b20a2caf17 100644
--- a/django/contrib/auth/models.py
+++ b/django/contrib/auth/models.py
@@ -47,6 +47,13 @@ def check_password(raw_password, enc_password):
 class SiteProfileNotAvailable(Exception):
     pass
 
+class PermissionManager(models.Manager):
+    def get_by_natural_key(self, codename, app_label, model):
+        return self.get(
+            codename=codename,
+            content_type=ContentType.objects.get_by_natural_key(app_label, model)
+        )
+
 class Permission(models.Model):
     """The permissions system provides a way to assign permissions to specific users and groups of users.
 
@@ -63,6 +70,7 @@ class Permission(models.Model):
     name = models.CharField(_('name'), max_length=50)
     content_type = models.ForeignKey(ContentType)
     codename = models.CharField(_('codename'), max_length=100)
+    objects = PermissionManager()
 
     class Meta:
         verbose_name = _('permission')
@@ -76,6 +84,10 @@ class Permission(models.Model):
             unicode(self.content_type),
             unicode(self.name))
 
+    def natural_key(self):
+        return (self.codename,) + self.content_type.natural_key()
+    natural_key.dependencies = ['contenttypes.contenttype']
+
 class Group(models.Model):
     """Groups are a generic way of categorizing users to apply permissions, or some other label, to those users. A user can belong to any number of groups.
 
diff --git a/django/contrib/contenttypes/models.py b/django/contrib/contenttypes/models.py
index def7ce6986..69d0806385 100644
--- a/django/contrib/contenttypes/models.py
+++ b/django/contrib/contenttypes/models.py
@@ -8,6 +8,13 @@ class ContentTypeManager(models.Manager):
     # This cache is shared by all the get_for_* methods.
     _cache = {}
 
+    def get_by_natural_key(self, app_label, model):
+        try:
+            ct = self.__class__._cache[(app_label, model)]
+        except KeyError:
+            ct = self.get(app_label=app_label, model=model)
+        return ct
+
     def get_for_model(self, model):
         """
         Returns the ContentType object for a given model, creating the
@@ -93,3 +100,6 @@ class ContentType(models.Model):
         so code that calls this method should catch it.
         """
         return self.model_class()._default_manager.get(**kwargs)
+
+    def natural_key(self):
+        return (self.app_label, self.model)