Changeset 7600

Timestamp:

06/09/08 09:03:35 (6 months ago)

Author:

russellm

Message:

Fixed #7350, #7202 -- Fixed serialization for multi-model inheritance, which had multiple problems:

• Serializers were including all superclass fields in their output. Now only local fields are included.
  
• Implicit OneToOne? primary keys were not correctly added to the metamodel, so they were always marked to be serialized, even though they were primary
  
• Model saving was too aggressive about creating new parent class instances during deserialization. Raw save on a model now skips saving of the parent class.
  

Files:

• django/trunk/django/core/serializers/base.py (modified) (1 diff)
• django/trunk/django/db/models/base.py (modified) (1 diff)
• django/trunk/django/db/models/options.py (modified) (1 diff)
• django/trunk/docs/serialization.txt (modified) (1 diff)
• django/trunk/tests/modeltests/model_inheritance/models.py (modified) (1 diff)
• django/trunk/tests/regressiontests/model_inheritance_regress (added)
• django/trunk/tests/regressiontests/model_inheritance_regress/__init__.py (added)
• django/trunk/tests/regressiontests/model_inheritance_regress/models.py (added)
• django/trunk/tests/regressiontests/serializers_regress/models.py (modified) (1 diff)
• django/trunk/tests/regressiontests/serializers_regress/tests.py (modified) (11 diffs)

django/trunk/django/core/serializers/base.py

@@ -39 +39 @@
-        for obj in queryset:
-            self.start_object(obj)
-
+local_
-                if field.serialize:
-                    if field.rel is None:

django/trunk/django/db/models/base.py

@@ -291 +291 @@
-            signal = False
-
-
-
-
+
+
+
+
+
+
+
+
-
-        non_pks = [f for f in meta.local_fields if not f.primary_key]
-
+
-        # First, try an UPDATE. If that doesn't update anything, do an INSERT.
-        pk_val = self._get_pk_val(meta)

django/trunk/django/db/models/options.py

@@ -103 +103 @@
-                field = self.parents.value_for_index(0)
-                field.primary_key = True
-pk = field
+setup_pk(field)
-            else:
-                auto = AutoField(verbose_name='ID', primary_key=True,

django/trunk/docs/serialization.txt

@@ -63 +63 @@
-    doesn't specify all the fields that are required by a model, the deserializer
-    will not be able to save deserialized instances.
+
+Inherited Models
+~~~~~~~~~~~~~~~~
+
+If you have a model that is defined using an `abstract base class`_, you don't
+have to do anything special to serialize that model. Just call the serializer
+on the object (or objects) that you want to serialize, and the output will be
+a complete representation of the serialized object.
+
+However, if you have a model that uses `multi-table inheritance`_, you also
+need to serialize all of the base classes for the model. This is because only
+the fields that are locally defined on the model will be serialized. For
+example, consider the following models::
+        
+        class Place(models.Model):
+                name = models.CharField(max_length=50)
+                
+        class Restaurant(Place):
+                serves_hot_dogs = models.BooleanField()
+                
+If you only serialize the Restaurant model::
+
+        data = serializers.serialize('xml', Restaurant.objects.all())
+
+the fields on the serialized output will only contain the `serves_hot_dogs`
+attribute. The `name` attribute of the base class will be ignored.
+
+In order to fully serialize your Restaurant instances, you will need to
+serialize the Place models as well::
+
+        all_objects = list(Restaurant.objects.all()) + list(Place.objects.all())
+        data = serializers.serialize('xml', all_objects)
+
+.. _abstract base class: http://www.djangoproject.com/documentation/model-api/#abstract-base-classes
+.. _multi-table inheritance: http://www.djangoproject.com/documentation/model-api/#multi-table-inheritance
-
-Deserializing data

django/trunk/tests/modeltests/model_inheritance/models.py

@@ -148 +148 @@
->>> ir = ItalianRestaurant(name='Ristorante Miron', address='1234 W. Ash', serves_hot_dogs=False, serves_pizza=False, serves_gnocchi=True, rating=4, chef=c)
->>> ir.save()
+>>> ItalianRestaurant.objects.filter(address='1234 W. Ash')
+[<ItalianRestaurant: Ristorante Miron the italian restaurant>]
+
->>> ir.address = '1234 W. Elm'
->>> ir.save()
+>>> ItalianRestaurant.objects.filter(address='1234 W. Elm')
+[<ItalianRestaurant: Ristorante Miron the italian restaurant>]
-
-# Make sure Restaurant and ItalianRestaurant have the right fields in the right

django/trunk/tests/regressiontests/serializers_regress/models.py

@@ -224 +224 @@
-        self.data = 666
-        super(ModifyingSaveData, self).save(raw)
+
+# Tests for serialization of models using inheritance.
+# Regression for #7202, #7350
+class AbstractBaseModel(models.Model):
+    parent_data = models.IntegerField()
+    class Meta:
+        abstract = True
+
+class InheritAbstractModel(AbstractBaseModel):
+    child_data = models.IntegerField()
+    
+class BaseModel(models.Model):
+    parent_data = models.IntegerField()
+
+class InheritBaseModel(BaseModel):
+    child_data = models.IntegerField()
+
+class ExplicitInheritBaseModel(BaseModel):
+    parent = models.OneToOneField(BaseModel)
+    child_data = models.IntegerField()

django/trunk/tests/regressiontests/serializers_regress/tests.py

@@ -33 +33 @@
-    instance.data = data
-    models.Model.save_base(instance, raw=True)
-instance
+[instance]
-
-def generic_create(pk, klass, data):
@@ -41 +41 @@
-    for tag in data[1:]:
-        instance.tags.create(data=tag)
-instance
+[instance]
-
-def fk_create(pk, klass, data):
@@ -47 +47 @@
-    setattr(instance, 'data_id', data)
-    models.Model.save_base(instance, raw=True)
-instance
+[instance]
-
-def m2m_create(pk, klass, data):
@@ -53 +53 @@
-    models.Model.save_base(instance, raw=True)
-    instance.data = data
-instance
+[instance]
-
-def o2o_create(pk, klass, data):
@@ -59 +59 @@
-    instance.data_id = data
-    models.Model.save_base(instance, raw=True)
-instance
+[instance]
-
-def pk_create(pk, klass, data):
@@ -65 +65 @@
-    instance.data = data
-    models.Model.save_base(instance, raw=True)
-
-
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-# A set of functions that can be used to compare
-# test data objects of various kinds
@@ -95 +108 @@
-    testcase.assertEqual(data, instance.data)
-
+def inherited_compare(testcase, pk, klass, data):
+    instance = klass.objects.get(id=pk)
+    for key,value in data.items():
+        testcase.assertEqual(value, getattr(instance,key))
+    
-# Define some data types. Each data type is
-# actually a pair of functions; one to create
@@ -104 +122 @@
-o2o_obj = (o2o_create, o2o_compare)
-pk_obj = (pk_create, pk_compare)
+inherited_obj = (inherited_create, inherited_compare)
-
-test_data = [
@@ -256 +275 @@
-    (data_obj, 800, AutoNowDateTimeData, datetime.datetime(2006,6,16,10,42,37)),
-    (data_obj, 810, ModifyingSaveData, 42),
+    
+    (inherited_obj, 900, InheritAbstractModel, {'child_data':37,'parent_data':42}),
+    (inherited_obj, 910, ExplicitInheritBaseModel, {'child_data':37,'parent_data':42}),
+    (inherited_obj, 920, InheritBaseModel, {'child_data':37,'parent_data':42}),
-]
-
@@ -278 +301 @@
-    # Create all the objects defined in the test data
-    objects = []
+    instance_count = {}
-    transaction.enter_transaction_management()
-    transaction.managed(True)
-    for (func, pk, klass, datum) in test_data:
-
+
+
-    transaction.commit()
-    transaction.leave_transaction_management()
-
+    # Get a count of the number of objects created for each class
+    for klass in instance_count:
+        instance_count[klass] = klass.objects.count()
+        
-    # Add the generic tagged objects to the object list
-    objects.extend(Tag.objects.all())
@@ -305 +334 @@
-        func[1](self, pk, klass, datum)
-
+    # Assert that the number of objects deserialized is the
+    # same as the number that was serialized.
+    for klass, count in instance_count.items():
+        self.assertEquals(count, klass.objects.count())
+
-def fieldsTest(format, self):
-    # Clear the database first