Merge master

docs/api-guide/fields.md

@@ -199,7 +199,7 @@ If you want to override this behavior, you'll need to declare the `DateTimeField
 
 **Signature:** `DateTimeField(format=None, input_formats=None)`
 
-* `format` - A string representing the output format.  If not specified, the `DATETIME_FORMAT` setting will be used, which defaults to `'iso-8601'`.
+* `format` - A string representing the output format.  If not specified, this defaults to `None`, which indicates that python `datetime` objects should be returned by `to_native`.  In this case the datetime encoding will be determined by the renderer. 
 * `input_formats` - A list of strings representing the input formats which may be used to parse the date. If not specified, the `DATETIME_INPUT_FORMATS` setting will be used, which defaults to `['iso-8601']`.
 
 DateTime format strings may either be [python strftime formats][strftime] which explicitly specifiy the format, or the special string `'iso-8601'`, which indicates that [ISO 8601][iso8601] style datetimes should be used. (eg `'2013-01-29T12:34:56.000000'`)
@@ -212,7 +212,7 @@ Corresponds to `django.db.models.fields.DateField`
 
 **Signature:** `DateField(format=None, input_formats=None)`
 
-* `format` - A string representing the output format.  If not specified, the `DATE_FORMAT` setting will be used, which defaults to `'iso-8601'`.
+* `format` - A string representing the output format.  If not specified, this defaults to `None`, which indicates that python `date` objects should be returned by `to_native`.  In this case the date encoding will be determined by the renderer.
 * `input_formats` - A list of strings representing the input formats which may be used to parse the date. If not specified, the `DATE_INPUT_FORMATS` setting will be used, which defaults to `['iso-8601']`. 
 
 Date format strings may either be [python strftime formats][strftime] which explicitly specifiy the format, or the special string `'iso-8601'`, which indicates that [ISO 8601][iso8601] style dates should be used. (eg `'2013-01-29'`)
@@ -227,7 +227,7 @@ Corresponds to `django.db.models.fields.TimeField`
 
 **Signature:** `TimeField(format=None, input_formats=None)`
 
-* `format` - A string representing the output format.  If not specified, the `TIME_FORMAT` setting will be used, which defaults to `'iso-8601'`.
+* `format` - A string representing the output format.  If not specified, this defaults to `None`, which indicates that python `time` objects should be returned by `to_native`.  In this case the time encoding will be determined by the renderer.
 * `input_formats` - A list of strings representing the input formats which may be used to parse the date. If not specified, the `TIME_INPUT_FORMATS` setting will be used, which defaults to `['iso-8601']`.
 
 Time format strings may either be [python strftime formats][strftime] which explicitly specifiy the format, or the special string `'iso-8601'`, which indicates that [ISO 8601][iso8601] style times should be used. (eg `'12:34:56.000000'`)
@@ -273,6 +273,49 @@ Django's regular [FILE_UPLOAD_HANDLERS] are used for handling uploaded files.
 
 ---
 
+# Custom fields
+
+If you want to create a custom field, you'll probably want to override either one or both of the `.to_native()` and `.from_native()` methods.  These two methods are used to convert between the intial datatype, and a primative, serializable datatype.  Primative datatypes may be any of a number, string, date/time/datetime or None.  They may also be any list or dictionary like object that only contains other primative objects.
+
+The `.to_native()` method is called to convert the initial datatype into a primative, serializable datatype.  The `from_native()` method is called to restore a primative datatype into it's initial representation.
+
+## Examples
+
+Let's look at an example of serializing a class that represents an RGB color value:
+
+    class Color(object):
+        """
+        A color represented in the RGB colorspace.
+        """
+        def __init__(self, red, green, blue):
+            assert(red >= 0 and green >= 0 and blue >= 0)
+            assert(red < 256 and green < 256 and blue < 256)
+            self.red, self.green, self.blue = red, green, blue
+
+    class ColourField(serializers.WritableField):
+        """
+        Color objects are serialized into "rgb(#, #, #)" notation.
+        """
+        def to_native(self, obj):
+            return "rgb(%d, %d, %d)" % (obj.red, obj.green, obj.blue)
+      
+        def from_native(self, data):
+            data = data.strip('rgb(').rstrip(')')
+            red, green, blue = [int(col) for col in data.split(',')]
+            return Color(red, green, blue)
+            
+
+By default field values are treated as mapping to an attribute on the object.  If you need to customize how the field value is accessed and set you need to override `.field_to_native()` and/or `.field_from_native()`.
+
+As an example, let's create a field that can be used represent the class name of the object being serialized:
+
+    class ClassNameField(serializers.Field):
+        def field_to_native(self, obj, field_name):
+            """
+            Serialize the object's class name.
+            """
+            return obj.__class__
+
 [cite]: https://docs.djangoproject.com/en/dev/ref/forms/api/#django.forms.Form.cleaned_data
 [FILE_UPLOAD_HANDLERS]: https://docs.djangoproject.com/en/dev/ref/settings/#std:setting-FILE_UPLOAD_HANDLERS
 [strftime]: http://docs.python.org/2/library/datetime.html#strftime-and-strptime-behavior

docs/api-guide/settings.md

@@ -192,44 +192,56 @@ Default: `'format'`
 
 ---
 
-## Date/Time formatting
+## Date and time formatting
 
 *The following settings are used to control how date and time representations may be parsed and rendered.*
 
 #### DATETIME_FORMAT
 
-A format string that should be used by default for rendering the output of `DateTimeField` serializer fields.
+A format string that should be used by default for rendering the output of `DateTimeField` serializer fields.  If `None`, then `DateTimeField` serializer fields will return python `datetime` objects, and the datetime encoding will be determined by the renderer.
 
-Default: `'iso-8601'`
+May be any of `None`, `'iso-8601'` or a python [strftime format][strftime] string.
+
+Default: `None'`
 
 #### DATETIME_INPUT_FORMATS
 
 A list of format strings that should be used by default for parsing inputs to `DateTimeField` serializer fields.
 
+May be a list including the string `'iso-8601'` or python [strftime format][strftime] strings.
+
 Default: `['iso-8601']`
 
 #### DATE_FORMAT
 
-A format string that should be used by default for rendering the output of `DateField` serializer fields.
+A format string that should be used by default for rendering the output of `DateField` serializer fields.  If `None`, then `DateField` serializer fields will return python `date` objects, and the date encoding will be determined by the renderer.
 
-Default: `'iso-8601'`
+May be any of `None`, `'iso-8601'` or a python [strftime format][strftime] string.
+
+Default: `None`
 
 #### DATE_INPUT_FORMATS
 
 A list of format strings that should be used by default for parsing inputs to `DateField` serializer fields.
 
+May be a list including the string `'iso-8601'` or python [strftime format][strftime] strings.
+
 Default: `['iso-8601']`
 
 #### TIME_FORMAT
 
-A format string that should be used by default for rendering the output of `TimeField` serializer fields.
+A format string that should be used by default for rendering the output of `TimeField` serializer fields.  If `None`, then `TimeField` serializer fields will return python `time` objects, and the time encoding will be determined by the renderer.
+
+May be any of `None`, `'iso-8601'` or a python [strftime format][strftime] string.
 
-Default: `'iso-8601'`
+Default: `None`
 
 #### TIME_INPUT_FORMATS
 
 A list of format strings that should be used by default for parsing inputs to `TimeField` serializer fields.
 
+May be a list including the string `'iso-8601'` or python [strftime format][strftime] strings.
+
 Default: `['iso-8601']`
 
 ---
@@ -243,3 +255,4 @@ The name of a parameter in the URL conf that may be used to provide a format suf
 Default: `'format'`
 
 [cite]: http://www.python.org/dev/peps/pep-0020/
+[strftime]: http://docs.python.org/2/library/time.html#time.strftime
\ No newline at end of file

docs/topics/release-notes.md

@@ -42,6 +42,8 @@ You can determine your currently installed version using `pip freeze`:
 
 ### Master
 
+* Regression fix: Date and time fields return date/time objects by default.  Fixes regressions caused by 2.2.2.  See [#743][743] for more details.
+* Bugfix: Fix 500 error is OAuth not attempted with OAuthAuthentication class installed.
 * `Serializer.save()` now supports arbitrary keyword args which are passed through to the object `.save()` method.  Mixins use `force_insert` and `force_update` where appropriate, resulting in one less database query.
 
 ### 2.2.4
@@ -434,6 +436,7 @@ This change will not affect user code, so long as it's following the recommended
 [django-deprecation-policy]: https://docs.djangoproject.com/en/dev/internals/release-process/#internal-release-deprecation-policy
 [defusedxml-announce]: http://blog.python.org/2013/02/announcing-defusedxml-fixes-for-xml.html
 [2.2-announcement]: 2.2-announcement.md
+[743]: https://github.com/tomchristie/django-rest-framework/pull/743
 [staticfiles14]: https://docs.djangoproject.com/en/1.4/howto/static-files/#with-a-template-tag
 [staticfiles13]: https://docs.djangoproject.com/en/1.3/howto/static-files/#with-a-template-tag
 [2.1.0-notes]: https://groups.google.com/d/topic/django-rest-framework/Vv2M0CMY9bg/discussion

rest_framework/authentication.py

@@ -204,6 +204,9 @@ class OAuthAuthentication(BaseAuthentication):
         except oauth.Error as err:
             raise exceptions.AuthenticationFailed(err.message)
 
+        if not oauth_request:
+            return None
+
         oauth_params = oauth_provider.consts.OAUTH_PARAMETERS_NAMES
 
         found = any(param for param in oauth_params if param in oauth_request)

rest_framework/fields.py

@@ -494,7 +494,7 @@ class DateField(WritableField):
     }
     empty = None
     input_formats = api_settings.DATE_INPUT_FORMATS
-    format = api_settings.DATE_FORMAT
+    format = None
 
     def __init__(self, input_formats=None, format=None, *args, **kwargs):
         self.input_formats = input_formats if input_formats is not None else self.input_formats
@@ -536,8 +536,8 @@ class DateField(WritableField):
         raise ValidationError(msg)
 
     def to_native(self, value):
-        if value is None:
-            return None
+        if value is None or self.format is None:
+            return value
 
         if isinstance(value, datetime.datetime):
             value = value.date()
@@ -557,7 +557,7 @@ class DateTimeField(WritableField):
     }
     empty = None
     input_formats = api_settings.DATETIME_INPUT_FORMATS
-    format = api_settings.DATETIME_FORMAT
+    format = None
 
     def __init__(self, input_formats=None, format=None, *args, **kwargs):
         self.input_formats = input_formats if input_formats is not None else self.input_formats
@@ -605,11 +605,14 @@ class DateTimeField(WritableField):
         raise ValidationError(msg)
 
     def to_native(self, value):
-        if value is None:
-            return None
+        if value is None or self.format is None:
+            return value
 
         if self.format.lower() == ISO_8601:
-            return value.isoformat()
+            ret = value.isoformat()
+            if ret.endswith('+00:00'):
+                ret = ret[:-6] + 'Z'
+            return ret
         return value.strftime(self.format)
 
 
@@ -623,7 +626,7 @@ class TimeField(WritableField):
     }
     empty = None
     input_formats = api_settings.TIME_INPUT_FORMATS
-    format = api_settings.TIME_FORMAT
+    format = None
 
     def __init__(self, input_formats=None, format=None, *args, **kwargs):
         self.input_formats = input_formats if input_formats is not None else self.input_formats
@@ -658,8 +661,8 @@ class TimeField(WritableField):
         raise ValidationError(msg)
 
     def to_native(self, value):
-        if value is None:
-            return None
+        if value is None or self.format is None:
+            return value
 
         if isinstance(value, datetime.datetime):
             value = value.time()

rest_framework/serializers.py

@@ -129,13 +129,15 @@ class BaseSerializer(WritableField):
     _dict_class = SortedDictWithMetadata
 
     def __init__(self, instance=None, data=None, files=None,
-                 context=None, partial=False, many=None, **kwargs):
+                 context=None, partial=False, many=None,
+                 allow_delete=False, **kwargs):
         super(BaseSerializer, self).__init__(**kwargs)
         self.opts = self._options_class(self.Meta)
         self.parent = None
         self.root = None
         self.partial = partial
         self.many = many
+        self.allow_delete = allow_delete
 
         self.context = context or {}
 
@@ -147,6 +149,13 @@ class BaseSerializer(WritableField):
         self._data = None
         self._files = None
         self._errors = None
+        self._deleted = None
+
+        if many and instance is not None and not hasattr(instance, '__iter__'):
+            raise ValueError('instance should be a queryset or other iterable with many=True')
+
+        if allow_delete and not many:
+            raise ValueError('allow_delete should only be used for bulk updates, but you have not set many=True')
 
     #####
     # Methods to determine which fields to use when (de)serializing objects.
@@ -387,6 +396,20 @@ class BaseSerializer(WritableField):
                 # Propagate errors up to our parent
                 raise NestedValidationError(serializer.errors)
 
+    def get_identity(self, data):
+        """
+        This hook is required for bulk update.
+        It is used to determine the canonical identity of a given object.
+
+        Note that the data has not been validated at this point, so we need
+        to make sure that we catch any cases of incorrect datatypes being
+        passed to this method.
+        """
+        try:
+            return data.get('id', None)
+        except AttributeError:
+            return None
+
     @property
     def errors(self):
         """
@@ -408,10 +431,33 @@ class BaseSerializer(WritableField):
             if many:
                 ret = []
                 errors = []
-                for item in data:
-                    ret.append(self.from_native(item, None))
-                    errors.append(self._errors)
-                self._errors = any(errors) and errors or []
+                update = self.object is not None
+
+                if update:
+                    # If this is a bulk update we need to map all the objects
+                    # to a canonical identity so we can determine which
+                    # individual object is being updated for each item in the
+                    # incoming data
+                    objects = self.object
+                    identities = [self.get_identity(self.to_native(obj)) for obj in objects]
+                    identity_to_objects = dict(zip(identities, objects))
+
+                if hasattr(data, '__iter__') and not isinstance(data, (dict, six.text_type)):
+                    for item in data:
+                        if update:
+                            # Determine which object we're updating
+                            identity = self.get_identity(item)
+                            self.object = identity_to_objects.pop(identity, None)
+
+                        ret.append(self.from_native(item, None))
+                        errors.append(self._errors)
+
+                    if update:
+                        self._deleted = identity_to_objects.values()
+
+                    self._errors = any(errors) and errors or []
+                else:
+                    self._errors = {'non_field_errors': ['Expected a list of items']}
             else:
                 ret = self.from_native(data, files)
 
@@ -450,6 +496,9 @@ class BaseSerializer(WritableField):
     def save_object(self, obj, **kwargs):
         obj.save(**kwargs)
 
+    def delete_object(self, obj):
+        obj.delete()
+
     def save(self, **kwargs):
         """
         Save the deserialized object and return it.
@@ -458,6 +507,10 @@ class BaseSerializer(WritableField):
             [self.save_object(item, **kwargs) for item in self.object]
         else:
             self.save_object(self.object, **kwargs)
+
+        if self.allow_delete and self._deleted:
+            [self.delete_object(item) for item in self._deleted]
+
         return self.object
 
 
@@ -765,3 +818,13 @@ class HyperlinkedModelSerializer(ModelSerializer):
             'many': to_many
         }
         return HyperlinkedRelatedField(**kwargs)
+
+    def get_identity(self, data):
+        """
+        This hook is required for bulk update.
+        We need to override the default, to use the url as the identity.
+        """
+        try:
+            return data.get('url', None)
+        except AttributeError:
+            return None

rest_framework/tests/fields.py

@@ -153,12 +153,22 @@ class DateFieldTest(TestCase):
 
     def test_to_native(self):
         """
-        Make sure to_native() returns isoformat as default.
+        Make sure to_native() returns datetime as default.
         """
         f = serializers.DateField()
 
         result_1 = f.to_native(datetime.date(1984, 7, 31))
 
+        self.assertEqual(datetime.date(1984, 7, 31), result_1)
+
+    def test_to_native_iso(self):
+        """
+        Make sure to_native() with 'iso-8601' returns iso formated date.
+        """
+        f = serializers.DateField(format='iso-8601')
+
+        result_1 = f.to_native(datetime.date(1984, 7, 31))
+
         self.assertEqual('1984-07-31', result_1)
 
     def test_to_native_custom_format(self):
@@ -289,6 +299,22 @@ class DateTimeFieldTest(TestCase):
         result_3 = f.to_native(datetime.datetime(1984, 7, 31, 4, 31, 59))
         result_4 = f.to_native(datetime.datetime(1984, 7, 31, 4, 31, 59, 200))
 
+        self.assertEqual(datetime.datetime(1984, 7, 31), result_1)
+        self.assertEqual(datetime.datetime(1984, 7, 31, 4, 31), result_2)
+        self.assertEqual(datetime.datetime(1984, 7, 31, 4, 31, 59), result_3)
+        self.assertEqual(datetime.datetime(1984, 7, 31, 4, 31, 59, 200), result_4)
+
+    def test_to_native_iso(self):
+        """
+        Make sure to_native() with format=iso-8601 returns iso formatted datetime.
+        """
+        f = serializers.DateTimeField(format='iso-8601')
+
+        result_1 = f.to_native(datetime.datetime(1984, 7, 31))
+        result_2 = f.to_native(datetime.datetime(1984, 7, 31, 4, 31))
+        result_3 = f.to_native(datetime.datetime(1984, 7, 31, 4, 31, 59))
+        result_4 = f.to_native(datetime.datetime(1984, 7, 31, 4, 31, 59, 200))
+
         self.assertEqual('1984-07-31T00:00:00', result_1)
         self.assertEqual('1984-07-31T04:31:00', result_2)
         self.assertEqual('1984-07-31T04:31:59', result_3)
@@ -419,13 +445,26 @@ class TimeFieldTest(TestCase):
 
     def test_to_native(self):
         """
-        Make sure to_native() returns isoformat as default.
+        Make sure to_native() returns time object as default.
         """
         f = serializers.TimeField()
         result_1 = f.to_native(datetime.time(4, 31))
         result_2 = f.to_native(datetime.time(4, 31, 59))
         result_3 = f.to_native(datetime.time(4, 31, 59, 200))
 
+        self.assertEqual(datetime.time(4, 31), result_1)
+        self.assertEqual(datetime.time(4, 31, 59), result_2)
+        self.assertEqual(datetime.time(4, 31, 59, 200), result_3)
+
+    def test_to_native_iso(self):
+        """
+        Make sure to_native() with format='iso-8601' returns iso formatted time.
+        """
+        f = serializers.TimeField(format='iso-8601')
+        result_1 = f.to_native(datetime.time(4, 31))
+        result_2 = f.to_native(datetime.time(4, 31, 59))
+        result_3 = f.to_native(datetime.time(4, 31, 59, 200))
+
         self.assertEqual('04:31:00', result_1)
         self.assertEqual('04:31:59', result_2)
         self.assertEqual('04:31:59.000200', result_3)

rest_framework/tests/filterset.py

@@ -65,7 +65,7 @@ class IntegrationTestFiltering(TestCase):
 
         self.objects = FilterableItem.objects
         self.data = [
-            {'id': obj.id, 'text': obj.text, 'decimal': obj.decimal, 'date': obj.date.isoformat()}
+            {'id': obj.id, 'text': obj.text, 'decimal': obj.decimal, 'date': obj.date}
             for obj in self.objects.all()
         ]
 
@@ -95,7 +95,7 @@ class IntegrationTestFiltering(TestCase):
         request = factory.get('/?date=%s' % search_date)  # search_date str: '2012-09-22'
         response = view(request).render()
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        expected_data = [f for f in self.data if datetime.datetime.strptime(f['date'], '%Y-%m-%d').date() == search_date]
+        expected_data = [f for f in self.data if f['date'] == search_date]
         self.assertEqual(response.data, expected_data)
 
     @unittest.skipUnless(django_filters, 'django-filters not installed')
@@ -125,7 +125,7 @@ class IntegrationTestFiltering(TestCase):
         request = factory.get('/?date=%s' % search_date)  # search_date str: '2012-10-02'
         response = view(request).render()
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        expected_data = [f for f in self.data if datetime.datetime.strptime(f['date'], '%Y-%m-%d').date() > search_date]
+        expected_data = [f for f in self.data if f['date'] > search_date]
         self.assertEqual(response.data, expected_data)
 
         # Tests that the text filter set with 'icontains' in the filter class works.
@@ -142,8 +142,7 @@ class IntegrationTestFiltering(TestCase):
         request = factory.get('/?decimal=%s&date=%s' % (search_decimal, search_date))
         response = view(request).render()
         self.assertEqual(response.status_code, status.HTTP_200_OK)
-        expected_data = [f for f in self.data if
-                         datetime.datetime.strptime(f['date'], '%Y-%m-%d').date() > search_date and
+        expected_data = [f for f in self.data if f['date'] > search_date and
                          f['decimal'] < search_decimal]
         self.assertEqual(response.data, expected_data)
 

rest_framework/tests/pagination.py

@@ -102,7 +102,7 @@ class IntegrationTestPaginationAndFiltering(TestCase):
 
         self.objects = FilterableItem.objects
         self.data = [
-            {'id': obj.id, 'text': obj.text, 'decimal': obj.decimal, 'date': obj.date.isoformat()}
+            {'id': obj.id, 'text': obj.text, 'decimal': obj.decimal, 'date': obj.date}
             for obj in self.objects.all()
         ]
 

rest_framework/tests/serializer.py

@@ -112,7 +112,7 @@ class BasicTests(TestCase):
         self.expected = {
             'email': 'tom@example.com',
             'content': 'Happy new year!',
-            'created': '2012-01-01T00:00:00',
+            'created': datetime.datetime(2012, 1, 1),
             'sub_comment': 'And Merry Christmas!'
         }
         self.person_data = {'name': 'dwight', 'age': 35}
@@ -261,34 +261,6 @@ class ValidationTests(TestCase):
         self.assertEqual(serializer.is_valid(), True)
         self.assertEqual(serializer.errors, {})
 
-    def test_bad_type_data_is_false(self):
-        """
-        Data of the wrong type is not valid.
-        """
-        data = ['i am', 'a', 'list']
-        serializer = CommentSerializer(self.comment, data=data, many=True)
-        self.assertEqual(serializer.is_valid(), False)
-        self.assertTrue(isinstance(serializer.errors, list))
-
-        self.assertEqual(
-            serializer.errors,
-            [
-                {'non_field_errors': ['Invalid data']},
-                {'non_field_errors': ['Invalid data']},
-                {'non_field_errors': ['Invalid data']}
-            ]
-        )
-
-        data = 'and i am a string'
-        serializer = CommentSerializer(self.comment, data=data)
-        self.assertEqual(serializer.is_valid(), False)
-        self.assertEqual(serializer.errors, {'non_field_errors': ['Invalid data']})
-
-        data = 42
-        serializer = CommentSerializer(self.comment, data=data)
-        self.assertEqual(serializer.is_valid(), False)
-        self.assertEqual(serializer.errors, {'non_field_errors': ['Invalid data']})
-
     def test_cross_field_validation(self):
 
         class CommentSerializerWithCrossFieldValidator(CommentSerializer):

rest_framework/tests/serializer_bulk_update.py

@@ -7,6 +7,9 @@ from rest_framework import serializers
 
 
 class BulkCreateSerializerTests(TestCase):
+    """
+    Creating multiple instances using serializers.
+    """
 
     def setUp(self):
         class BookSerializer(serializers.Serializer):
@@ -71,3 +74,181 @@ class BulkCreateSerializerTests(TestCase):
         self.assertEqual(serializer.is_valid(), False)
         self.assertEqual(serializer.errors, expected_errors)
 
+    def test_invalid_list_datatype(self):
+        """
+        Data containing list of incorrect data type should return errors.
+        """
+        data = ['foo', 'bar', 'baz']
+        serializer = self.BookSerializer(data=data, many=True)
+        self.assertEqual(serializer.is_valid(), False)
+
+        expected_errors = [
+                {'non_field_errors': ['Invalid data']},
+                {'non_field_errors': ['Invalid data']},
+                {'non_field_errors': ['Invalid data']}
+        ]
+
+        self.assertEqual(serializer.errors, expected_errors)
+
+    def test_invalid_single_datatype(self):
+        """
+        Data containing a single incorrect data type should return errors.
+        """
+        data = 123
+        serializer = self.BookSerializer(data=data, many=True)
+        self.assertEqual(serializer.is_valid(), False)
+
+        expected_errors = {'non_field_errors': ['Expected a list of items']}
+
+        self.assertEqual(serializer.errors, expected_errors)
+
+    def test_invalid_single_object(self):
+        """
+        Data containing only a single object, instead of a list of objects
+        should return errors.
+        """
+        data = {
+            'id': 0,
+            'title': 'The electric kool-aid acid test',
+            'author': 'Tom Wolfe'
+        }
+        serializer = self.BookSerializer(data=data, many=True)
+        self.assertEqual(serializer.is_valid(), False)
+
+        expected_errors = {'non_field_errors': ['Expected a list of items']}
+
+        self.assertEqual(serializer.errors, expected_errors)
+
+
+class BulkUpdateSerializerTests(TestCase):
+    """
+    Updating multiple instances using serializers.
+    """
+
+    def setUp(self):
+        class Book(object):
+            """
+            A data type that can be persisted to a mock storage backend
+            with `.save()` and `.delete()`.
+            """
+            object_map = {}
+
+            def __init__(self, id, title, author):
+                self.id = id
+                self.title = title
+                self.author = author
+
+            def save(self):
+                Book.object_map[self.id] = self
+
+            def delete(self):
+                del Book.object_map[self.id]
+
+        class BookSerializer(serializers.Serializer):
+            id = serializers.IntegerField()
+            title = serializers.CharField(max_length=100)
+            author = serializers.CharField(max_length=100)
+
+            def restore_object(self, attrs, instance=None):
+                if instance:
+                    instance.id = attrs['id']
+                    instance.title = attrs['title']
+                    instance.author = attrs['author']
+                    return instance
+                return Book(**attrs)
+
+        self.Book = Book
+        self.BookSerializer = BookSerializer
+
+        data = [
+            {
+                'id': 0,
+                'title': 'The electric kool-aid acid test',
+                'author': 'Tom Wolfe'
+            }, {
+                'id': 1,
+                'title': 'If this is a man',
+                'author': 'Primo Levi'
+            }, {
+                'id': 2,
+                'title': 'The wind-up bird chronicle',
+                'author': 'Haruki Murakami'
+            }
+        ]
+
+        for item in data:
+            book = Book(item['id'], item['title'], item['author'])
+            book.save()
+
+    def books(self):
+        """
+        Return all the objects in the mock storage backend.
+        """
+        return self.Book.object_map.values()
+
+    def test_bulk_update_success(self):
+        """
+        Correct bulk update serialization should return the input data.
+        """
+        data = [
+            {
+                'id': 0,
+                'title': 'The electric kool-aid acid test',
+                'author': 'Tom Wolfe'
+            }, {
+                'id': 2,
+                'title': 'Kafka on the shore',
+                'author': 'Haruki Murakami'
+            }
+        ]
+        serializer = self.BookSerializer(self.books(), data=data, many=True, allow_delete=True)
+        self.assertEqual(serializer.is_valid(), True)
+        self.assertEqual(serializer.data, data)
+        serializer.save()
+        new_data = self.BookSerializer(self.books(), many=True).data
+        self.assertEqual(data, new_data)
+
+    def test_bulk_update_and_create(self):
+        """
+        Bulk update serialization may also include created items.
+        """
+        data = [
+            {
+                'id': 0,
+                'title': 'The electric kool-aid acid test',
+                'author': 'Tom Wolfe'
+            }, {
+                'id': 3,
+                'title': 'Kafka on the shore',
+                'author': 'Haruki Murakami'
+            }
+        ]
+        serializer = self.BookSerializer(self.books(), data=data, many=True, allow_delete=True)
+        self.assertEqual(serializer.is_valid(), True)
+        self.assertEqual(serializer.data, data)
+        serializer.save()
+        new_data = self.BookSerializer(self.books(), many=True).data
+        self.assertEqual(data, new_data)
+
+    def test_bulk_update_error(self):
+        """
+        Incorrect bulk update serialization should return error data.
+        """
+        data = [
+            {
+                'id': 0,
+                'title': 'The electric kool-aid acid test',
+                'author': 'Tom Wolfe'
+            }, {
+                'id': 'foo',
+                'title': 'Kafka on the shore',
+                'author': 'Haruki Murakami'
+            }
+        ]
+        expected_errors = [
+            {},
+            {'id': ['Enter a whole number.']}
+        ]
+        serializer = self.BookSerializer(self.books(), data=data, many=True, allow_delete=True)
+        self.assertEqual(serializer.is_valid(), False)
+        self.assertEqual(serializer.errors, expected_errors)