Reverting r14994 (at request of SmileyChris) because of some backwards compatibility issues that need to be resolved.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14995 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/core/serializers/base.py

@@ -170,21 +170,3 @@ class DeserializedObject(object):
         # prevent a second (possibly accidental) call to save() from saving
         # the m2m data twice.
         self.m2m_data = None
-
-def build_instance(Model, data, db):
-    """
-    Build a model instance.
-
-    If the model instance doesn't have a primary key and the model supports
-    natural keys, try to retrieve it from the database.
-    """
-    obj = Model(**data)
-    if obj.pk is None and hasattr(Model, 'natural_key') and\
-            hasattr(Model._default_manager, 'get_by_natural_key'):
-        pk = obj.natural_key()
-        try:
-            obj.pk = Model._default_manager.db_manager(db)\
-                                           .get_by_natural_key(*pk).pk
-        except Model.DoesNotExist:
-            pass
-    return obj

django/core/serializers/python.py

@@ -27,13 +27,11 @@ class Serializer(base.Serializer):
         self._current = {}
 
     def end_object(self, obj):
-        data = {
+        self.objects.append({
-            "model": smart_unicode(obj._meta),
+            "model"  : smart_unicode(obj._meta),
-            "fields": self._current
+            "pk"     : smart_unicode(obj._get_pk_val(), strings_only=True),
-        }
+            "fields" : self._current
-        if not self.use_natural_keys or not hasattr(obj, 'natural_key'):
+        })
-            data['pk'] = smart_unicode(obj._get_pk_val(), strings_only=True)
-        self.objects.append(data)
         self._current = None
 
     def handle_field(self, obj, field):
@@ -84,9 +82,7 @@ def Deserializer(object_list, **options):
     for d in object_list:
         # Look up the model and starting build a dict of data for it.
         Model = _get_model(d["model"])
-        data = {}
+        data = {Model._meta.pk.attname : Model._meta.pk.to_python(d["pk"])}
-        if 'pk' in d:
-            data[Model._meta.pk.attname] = Model._meta.pk.to_python(d['pk'])
         m2m_data = {}
 
         # Handle each field
@@ -131,9 +127,7 @@ def Deserializer(object_list, **options):
             else:
                 data[field.name] = field.to_python(field_value)
 
-        obj = base.build_instance(Model, data, db)
+        yield base.DeserializedObject(Model(**data), m2m_data)
-
-        yield base.DeserializedObject(obj, m2m_data)
 
 def _get_model(model_identifier):
     """

django/core/serializers/xml_serializer.py

@@ -42,12 +42,16 @@ class Serializer(base.Serializer):
             raise base.SerializationError("Non-model object (%s) encountered during serialization" % type(obj))
 
         self.indent(1)
-        object_data = {"model": smart_unicode(obj._meta)}
-        if not self.use_natural_keys or not hasattr(obj, 'natural_key'):
         obj_pk = obj._get_pk_val()
-            if obj_pk is not None:
+        if obj_pk is None:
-                object_data['pk'] = smart_unicode(obj_pk)
+            attrs = {"model": smart_unicode(obj._meta),}
-        self.xml.startElement("object", object_data)
+        else:
+            attrs = {
+                "pk": smart_unicode(obj._get_pk_val()),
+                "model": smart_unicode(obj._meta),
+            }
+
+        self.xml.startElement("object", attrs)
 
     def end_object(self, obj):
         """
@@ -169,10 +173,13 @@ class Deserializer(base.Deserializer):
         Model = self._get_model_from_node(node, "model")
 
         # Start building a data dictionary from the object.
-        data = {}
+        # If the node is missing the pk set it to None
-        if node.hasAttribute('pk'):
+        if node.hasAttribute("pk"):
-            data[Model._meta.pk.attname] = Model._meta.pk.to_python(
+            pk = node.getAttribute("pk")
-                                                    node.getAttribute('pk'))
+        else:
+            pk = None
+
+        data = {Model._meta.pk.attname : Model._meta.pk.to_python(pk)}
 
         # Also start building a dict of m2m data (this is saved as
         # {m2m_accessor_attribute : [list_of_related_objects]})
@@ -203,10 +210,8 @@ class Deserializer(base.Deserializer):
                     value = field.to_python(getInnerText(field_node).strip())
                 data[field.name] = value
 
-        obj = base.build_instance(Model, data, self.db)
-
         # Return a DeserializedObject so that the m2m data has a place to live.
-        return base.DeserializedObject(obj, m2m_data)
+        return base.DeserializedObject(Model(**data), m2m_data)
 
     def _handle_fk_field_node(self, node, field):
         """

docs/topics/serialization.txt

@@ -307,12 +307,6 @@ into the primary key of an actual ``Person`` object.
     fields will be effectively unique, you can still use those fields
     as a natural key.
 
-.. versionchanged:: 1.3
-
-Deserialization of objects with no primary key will always check whether the
-model's manager has a ``get_by_natural_key()`` method and if so, use it to
-populate the deserialized object's primary key.
-
 Serialization of natural keys
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -359,23 +353,6 @@ use the `--natural` command line flag to generate natural keys.
     natural keys during serialization, but *not* be able to load those
     key values, just don't define the ``get_by_natural_key()`` method.
 
-.. versionchanged:: 1.3
-
-When ``use_natural_keys=True`` is specified, the primary key is no longer
-provided in the serialized data of this object since it can be calculated
-during deserialization::
-
-    ...
-    {
-        "model": "store.person",
-        "fields": {
-            "first_name": "Douglas",
-            "last_name": "Adams",
-            "birth_date": "1952-03-11",
-        }
-    }
-    ...
-
 Dependencies during serialization
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

tests/regressiontests/serializers_regress/models.py

@@ -264,17 +264,3 @@ class LengthModel(models.Model):
 
     def __len__(self):
         return self.data
-
-#Tests for natural keys.
-class BookManager(models.Manager):
-    def get_by_natural_key(self, isbn13):
-        return self.get(isbn13=isbn13)
-
-class Book(models.Model):
-    isbn13 = models.CharField(max_length=14)
-    title = models.CharField(max_length=100)
-
-    objects = BookManager()
-
-    def natural_key(self):
-        return (self.isbn13,)

tests/regressiontests/serializers_regress/tests.py

@@ -414,36 +414,8 @@ def streamTest(format, self):
     self.assertEqual(string_data, stream.getvalue())
     stream.close()
 
-def naturalKeyTest(format, self):
-    book1 = {'isbn13': '978-1590597255', 'title': 'The Definitive Guide to '
-             'Django: Web Development Done Right'}
-    book2 = {'isbn13':'978-1590599969', 'title': 'Practical Django Projects'}
-
-    # Create the books.
-    adrian = Book.objects.create(**book1)
-    james = Book.objects.create(**book2)
-
-    # Serialize the books.
-    string_data = serializers.serialize(format, Book.objects.all(), indent=2,
-                                        use_natural_keys=True)
-
-    # Delete one book (to prove that the natural key generation will only
-    # restore the primary keys of books found in the database via the
-    # get_natural_key manager method).
-    james.delete()
-
-    # Deserialize and test.
-    books = list(serializers.deserialize(format, string_data))
-    self.assertEqual(len(books), 2)
-    self.assertEqual(books[0].object.title, book1['title'])
-    self.assertEqual(books[0].object.pk, adrian.pk)
-    self.assertEqual(books[1].object.title, book2['title'])
-    self.assertEqual(books[1].object.pk, None)
-
 for format in serializers.get_serializer_formats():
     setattr(SerializerTests, 'test_' + format + '_serializer', curry(serializerTest, format))
     setattr(SerializerTests, 'test_' + format + '_serializer_fields', curry(fieldsTest, format))
-    setattr(SerializerTests, 'test_' + format + '_serializer_natural_key',
-            curry(naturalKeyTest, format))
     if format != 'python':
         setattr(SerializerTests, 'test_' + format + '_serializer_stream', curry(streamTest, format))