diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py index 0b0c2c9cc..26c34044c 100644 --- a/rest_framework/serializers.py +++ b/rest_framework/serializers.py @@ -20,6 +20,25 @@ from rest_framework.relations import * from rest_framework.fields import * +class NestedValidationError(ValidationError): + """ + The default ValidationError behavior is to stringify each item in the list + if the messages are a list of error messages. + + In the case of nested serializers, where the parent has many children, + then the child's `serializer.errors` will be a list of dicts. In the case + of a single child, the `serializer.errors` will be a dict. + + We need to override the default behavior to get properly nested error dicts. + """ + + def __init__(self, message): + if isinstance(message, dict): + self.messages = [message] + else: + self.messages = message + + class DictWithMetadata(dict): """ A dict-like object, that can have additional properties attached. @@ -98,7 +117,7 @@ class SerializerOptions(object): self.exclude = getattr(meta, 'exclude', ()) -class BaseSerializer(Field): +class BaseSerializer(WritableField): """ This is the Serializer implementation. We need to implement it as `BaseSerializer` due to metaclass magicks. @@ -110,9 +129,9 @@ class BaseSerializer(Field): _dict_class = SortedDictWithMetadata def __init__(self, instance=None, data=None, files=None, - context=None, partial=False, many=None, source=None, - allow_delete=False): - super(BaseSerializer, self).__init__(source=source) + 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 @@ -305,40 +324,77 @@ class BaseSerializer(Field): def field_to_native(self, obj, field_name): """ - Override default so that we can apply ModelSerializer as a nested - field to relationships. + Override default so that the serializer can be used as a nested field + across relationships. """ if self.source == '*': return self.to_native(obj) try: - if self.source: - for component in self.source.split('.'): - obj = getattr(obj, component) - if is_simple_callable(obj): - obj = obj() - else: - obj = getattr(obj, field_name) - if is_simple_callable(obj): - obj = obj() + source = self.source or field_name + value = obj + + for component in source.split('.'): + value = get_component(value, component) + if value is None: + break except ObjectDoesNotExist: return None - # If the object has an "all" method, assume it's a relationship - if is_simple_callable(getattr(obj, 'all', None)): - return [self.to_native(item) for item in obj.all()] + if is_simple_callable(getattr(value, 'all', None)): + return [self.to_native(item) for item in value.all()] - if obj is None: + if value is None: return None if self.many is not None: many = self.many else: - many = hasattr(obj, '__iter__') and not isinstance(obj, (Page, dict, six.text_type)) + many = hasattr(value, '__iter__') and not isinstance(value, (Page, dict, six.text_type)) if many: - return [self.to_native(item) for item in obj] - return self.to_native(obj) + return [self.to_native(item) for item in value] + return self.to_native(value) + + def field_from_native(self, data, files, field_name, into): + """ + Override default so that the serializer can be used as a writable + nested field across relationships. + """ + if self.read_only: + return + + try: + value = data[field_name] + except KeyError: + if self.default is not None and not self.partial: + # Note: partial updates shouldn't set defaults + value = copy.deepcopy(self.default) + else: + if self.required: + raise ValidationError(self.error_messages['required']) + return + + # Set the serializer object if it exists + obj = getattr(self.parent.object, field_name) if self.parent.object else None + + if value in (None, ''): + into[(self.source or field_name)] = None + else: + kwargs = { + 'instance': obj, + 'data': value, + 'context': self.context, + 'partial': self.partial, + 'many': self.many + } + serializer = self.__class__(**kwargs) + + if serializer.is_valid(): + into[self.source or field_name] = serializer.object + else: + # Propagate errors up to our parent + raise NestedValidationError(serializer.errors) def get_identity(self, data): """ @@ -637,33 +693,43 @@ class ModelSerializer(Serializer): """ Restore the model instance. """ - self.m2m_data = {} - self.related_data = {} + m2m_data = {} + related_data = {} + meta = self.opts.model._meta - # Reverse fk relations - for (obj, model) in self.opts.model._meta.get_all_related_objects_with_model(): + # Reverse fk or one-to-one relations + for (obj, model) in meta.get_all_related_objects_with_model(): field_name = obj.field.related_query_name() if field_name in attrs: - self.related_data[field_name] = attrs.pop(field_name) + related_data[field_name] = attrs.pop(field_name) # Reverse m2m relations - for (obj, model) in self.opts.model._meta.get_all_related_m2m_objects_with_model(): + for (obj, model) in meta.get_all_related_m2m_objects_with_model(): field_name = obj.field.related_query_name() if field_name in attrs: - self.m2m_data[field_name] = attrs.pop(field_name) + m2m_data[field_name] = attrs.pop(field_name) # Forward m2m relations - for field in self.opts.model._meta.many_to_many: + for field in meta.many_to_many: if field.name in attrs: - self.m2m_data[field.name] = attrs.pop(field.name) + m2m_data[field.name] = attrs.pop(field.name) + # Update an existing instance... if instance is not None: for key, val in attrs.items(): setattr(instance, key, val) + # ...or create a new instance else: instance = self.opts.model(**attrs) + # Any relations that cannot be set until we've + # saved the model get hidden away on these + # private attributes, so we can deal with them + # at the point of save. + instance._related_data = related_data + instance._m2m_data = m2m_data + return instance def from_native(self, data, files): @@ -680,15 +746,24 @@ class ModelSerializer(Serializer): """ obj.save(**kwargs) - if getattr(self, 'm2m_data', None): - for accessor_name, object_list in self.m2m_data.items(): - setattr(self.object, accessor_name, object_list) - self.m2m_data = {} + if getattr(obj, '_m2m_data', None): + for accessor_name, object_list in obj._m2m_data.items(): + setattr(obj, accessor_name, object_list) + del(obj._m2m_data) - if getattr(self, 'related_data', None): - for accessor_name, object_list in self.related_data.items(): - setattr(self.object, accessor_name, object_list) - self.related_data = {} + if getattr(obj, '_related_data', None): + for accessor_name, related in obj._related_data.items(): + if related is None: + previous = getattr(obj, accessor_name, related) + if previous: + previous.delete() + elif isinstance(related, models.Model): + fk_field = obj._meta.get_field_by_name(accessor_name)[0].field.name + setattr(related, fk_field, obj) + self.save_object(related) + else: + setattr(obj, accessor_name, related) + del(obj._related_data) class HyperlinkedModelSerializerOptions(ModelSerializerOptions): diff --git a/rest_framework/tests/relations_nested.py b/rest_framework/tests/relations_nested.py index a125ba656..4592e5593 100644 --- a/rest_framework/tests/relations_nested.py +++ b/rest_framework/tests/relations_nested.py @@ -1,115 +1,125 @@ from __future__ import unicode_literals +from django.db import models from django.test import TestCase from rest_framework import serializers -from rest_framework.tests.models import ForeignKeyTarget, ForeignKeySource, NullableForeignKeySource, OneToOneTarget, NullableOneToOneSource -class ForeignKeySourceSerializer(serializers.ModelSerializer): +class OneToOneTarget(models.Model): + name = models.CharField(max_length=100) + + +class OneToOneTargetSource(models.Model): + name = models.CharField(max_length=100) + target = models.OneToOneField(OneToOneTarget, null=True, blank=True, + related_name='target_source') + + +class OneToOneSource(models.Model): + name = models.CharField(max_length=100) + target_source = models.OneToOneField(OneToOneTargetSource, related_name='source') + + +class OneToOneSourceSerializer(serializers.ModelSerializer): class Meta: - depth = 1 - model = ForeignKeySource + model = OneToOneSource + exclude = ('target_source', ) -class FlatForeignKeySourceSerializer(serializers.ModelSerializer): - class Meta: - model = ForeignKeySource - - -class ForeignKeyTargetSerializer(serializers.ModelSerializer): - sources = FlatForeignKeySourceSerializer(many=True) +class OneToOneTargetSourceSerializer(serializers.ModelSerializer): + source = OneToOneSourceSerializer() class Meta: - model = ForeignKeyTarget + model = OneToOneTargetSource + exclude = ('target', ) -class NullableForeignKeySourceSerializer(serializers.ModelSerializer): - class Meta: - depth = 1 - model = NullableForeignKeySource - - -class NullableOneToOneSourceSerializer(serializers.ModelSerializer): - class Meta: - model = NullableOneToOneSource - - -class NullableOneToOneTargetSerializer(serializers.ModelSerializer): - nullable_source = NullableOneToOneSourceSerializer() +class OneToOneTargetSerializer(serializers.ModelSerializer): + target_source = OneToOneTargetSourceSerializer() class Meta: model = OneToOneTarget -class ReverseForeignKeyTests(TestCase): +class NestedOneToOneTests(TestCase): def setUp(self): - target = ForeignKeyTarget(name='target-1') - target.save() - new_target = ForeignKeyTarget(name='target-2') - new_target.save() for idx in range(1, 4): - source = ForeignKeySource(name='source-%d' % idx, target=target) + target = OneToOneTarget(name='target-%d' % idx) + target.save() + target_source = OneToOneTargetSource(name='target-source-%d' % idx, target=target) + target_source.save() + source = OneToOneSource(name='source-%d' % idx, target_source=target_source) source.save() - def test_foreign_key_retrieve(self): - queryset = ForeignKeySource.objects.all() - serializer = ForeignKeySourceSerializer(queryset, many=True) - expected = [ - {'id': 1, 'name': 'source-1', 'target': {'id': 1, 'name': 'target-1'}}, - {'id': 2, 'name': 'source-2', 'target': {'id': 1, 'name': 'target-1'}}, - {'id': 3, 'name': 'source-3', 'target': {'id': 1, 'name': 'target-1'}}, - ] - self.assertEqual(serializer.data, expected) - - def test_reverse_foreign_key_retrieve(self): - queryset = ForeignKeyTarget.objects.all() - serializer = ForeignKeyTargetSerializer(queryset, many=True) - expected = [ - {'id': 1, 'name': 'target-1', 'sources': [ - {'id': 1, 'name': 'source-1', 'target': 1}, - {'id': 2, 'name': 'source-2', 'target': 1}, - {'id': 3, 'name': 'source-3', 'target': 1}, - ]}, - {'id': 2, 'name': 'target-2', 'sources': [ - ]} - ] - self.assertEqual(serializer.data, expected) - - -class NestedNullableForeignKeyTests(TestCase): - def setUp(self): - target = ForeignKeyTarget(name='target-1') - target.save() - for idx in range(1, 4): - if idx == 3: - target = None - source = NullableForeignKeySource(name='source-%d' % idx, target=target) - source.save() - - def test_foreign_key_retrieve_with_null(self): - queryset = NullableForeignKeySource.objects.all() - serializer = NullableForeignKeySourceSerializer(queryset, many=True) - expected = [ - {'id': 1, 'name': 'source-1', 'target': {'id': 1, 'name': 'target-1'}}, - {'id': 2, 'name': 'source-2', 'target': {'id': 1, 'name': 'target-1'}}, - {'id': 3, 'name': 'source-3', 'target': None}, - ] - self.assertEqual(serializer.data, expected) - - -class NestedNullableOneToOneTests(TestCase): - def setUp(self): - target = OneToOneTarget(name='target-1') - target.save() - new_target = OneToOneTarget(name='target-2') - new_target.save() - source = NullableOneToOneSource(name='source-1', target=target) - source.save() - - def test_reverse_foreign_key_retrieve_with_null(self): + def test_one_to_one_retrieve(self): queryset = OneToOneTarget.objects.all() - serializer = NullableOneToOneTargetSerializer(queryset, many=True) + serializer = OneToOneTargetSerializer(queryset) expected = [ - {'id': 1, 'name': 'target-1', 'nullable_source': {'id': 1, 'name': 'source-1', 'target': 1}}, - {'id': 2, 'name': 'target-2', 'nullable_source': None}, + {'id': 1, 'name': 'target-1', 'target_source': {'id': 1, 'name': 'target-source-1', 'source': {'id': 1, 'name': 'source-1'}}}, + {'id': 2, 'name': 'target-2', 'target_source': {'id': 2, 'name': 'target-source-2', 'source': {'id': 2, 'name': 'source-2'}}}, + {'id': 3, 'name': 'target-3', 'target_source': {'id': 3, 'name': 'target-source-3', 'source': {'id': 3, 'name': 'source-3'}}} + ] + self.assertEqual(serializer.data, expected) + + def test_one_to_one_create(self): + data = {'id': 4, 'name': 'target-4', 'target_source': {'id': 4, 'name': 'target-source-4', 'source': {'id': 4, 'name': 'source-4'}}} + serializer = OneToOneTargetSerializer(data=data) + self.assertTrue(serializer.is_valid()) + obj = serializer.save() + self.assertEqual(serializer.data, data) + self.assertEqual(obj.name, 'target-4') + + # Ensure (target 4, target_source 4, source 4) are added, and + # everything else is as expected. + queryset = OneToOneTarget.objects.all() + serializer = OneToOneTargetSerializer(queryset) + expected = [ + {'id': 1, 'name': 'target-1', 'target_source': {'id': 1, 'name': 'target-source-1', 'source': {'id': 1, 'name': 'source-1'}}}, + {'id': 2, 'name': 'target-2', 'target_source': {'id': 2, 'name': 'target-source-2', 'source': {'id': 2, 'name': 'source-2'}}}, + {'id': 3, 'name': 'target-3', 'target_source': {'id': 3, 'name': 'target-source-3', 'source': {'id': 3, 'name': 'source-3'}}}, + {'id': 4, 'name': 'target-4', 'target_source': {'id': 4, 'name': 'target-source-4', 'source': {'id': 4, 'name': 'source-4'}}} + ] + self.assertEqual(serializer.data, expected) + + def test_one_to_one_create_with_invalid_data(self): + data = {'id': 4, 'name': 'target-4', 'target_source': {'id': 4, 'name': 'target-source-4', 'source': {'id': 4}}} + serializer = OneToOneTargetSerializer(data=data) + self.assertFalse(serializer.is_valid()) + self.assertEqual(serializer.errors, {'target_source': [{'source': [{'name': ['This field is required.']}]}]}) + + def test_one_to_one_update(self): + data = {'id': 3, 'name': 'target-3-updated', 'target_source': {'id': 3, 'name': 'target-source-3-updated', 'source': {'id': 3, 'name': 'source-3-updated'}}} + instance = OneToOneTarget.objects.get(pk=3) + serializer = OneToOneTargetSerializer(instance, data=data) + self.assertTrue(serializer.is_valid()) + obj = serializer.save() + self.assertEqual(serializer.data, data) + self.assertEqual(obj.name, 'target-3-updated') + + # Ensure (target 3, target_source 3, source 3) are updated, + # and everything else is as expected. + queryset = OneToOneTarget.objects.all() + serializer = OneToOneTargetSerializer(queryset) + expected = [ + {'id': 1, 'name': 'target-1', 'target_source': {'id': 1, 'name': 'target-source-1', 'source': {'id': 1, 'name': 'source-1'}}}, + {'id': 2, 'name': 'target-2', 'target_source': {'id': 2, 'name': 'target-source-2', 'source': {'id': 2, 'name': 'source-2'}}}, + {'id': 3, 'name': 'target-3-updated', 'target_source': {'id': 3, 'name': 'target-source-3-updated', 'source': {'id': 3, 'name': 'source-3-updated'}}} + ] + self.assertEqual(serializer.data, expected) + + def test_one_to_one_delete(self): + data = {'id': 3, 'name': 'target-3', 'target_source': None} + instance = OneToOneTarget.objects.get(pk=3) + serializer = OneToOneTargetSerializer(instance, data=data) + self.assertTrue(serializer.is_valid()) + serializer.save() + + # Ensure (target_source 3, source 3) are deleted, + # and everything else is as expected. + queryset = OneToOneTarget.objects.all() + serializer = OneToOneTargetSerializer(queryset) + expected = [ + {'id': 1, 'name': 'target-1', 'target_source': {'id': 1, 'name': 'target-source-1', 'source': {'id': 1, 'name': 'source-1'}}}, + {'id': 2, 'name': 'target-2', 'target_source': {'id': 2, 'name': 'target-source-2', 'source': {'id': 2, 'name': 'source-2'}}}, + {'id': 3, 'name': 'target-3', 'target_source': None} ] self.assertEqual(serializer.data, expected) diff --git a/rest_framework/tests/serializer_nested.py b/rest_framework/tests/serializer_nested.py new file mode 100644 index 000000000..6a29c6523 --- /dev/null +++ b/rest_framework/tests/serializer_nested.py @@ -0,0 +1,246 @@ +""" +Tests to cover nested serializers. + +Doesn't cover model serializers. +""" +from __future__ import unicode_literals +from django.test import TestCase +from rest_framework import serializers + + +class WritableNestedSerializerBasicTests(TestCase): + """ + Tests for deserializing nested entities. + Basic tests that use serializers that simply restore to dicts. + """ + + def setUp(self): + class TrackSerializer(serializers.Serializer): + order = serializers.IntegerField() + title = serializers.CharField(max_length=100) + duration = serializers.IntegerField() + + class AlbumSerializer(serializers.Serializer): + album_name = serializers.CharField(max_length=100) + artist = serializers.CharField(max_length=100) + tracks = TrackSerializer(many=True) + + self.AlbumSerializer = AlbumSerializer + + def test_nested_validation_success(self): + """ + Correct nested serialization should return the input data. + """ + + data = { + 'album_name': 'Discovery', + 'artist': 'Daft Punk', + 'tracks': [ + {'order': 1, 'title': 'One More Time', 'duration': 235}, + {'order': 2, 'title': 'Aerodynamic', 'duration': 184}, + {'order': 3, 'title': 'Digital Love', 'duration': 239} + ] + } + + serializer = self.AlbumSerializer(data=data) + self.assertEqual(serializer.is_valid(), True) + self.assertEqual(serializer.object, data) + + def test_nested_validation_error(self): + """ + Incorrect nested serialization should return appropriate error data. + """ + + data = { + 'album_name': 'Discovery', + 'artist': 'Daft Punk', + 'tracks': [ + {'order': 1, 'title': 'One More Time', 'duration': 235}, + {'order': 2, 'title': 'Aerodynamic', 'duration': 184}, + {'order': 3, 'title': 'Digital Love', 'duration': 'foobar'} + ] + } + expected_errors = { + 'tracks': [ + {}, + {}, + {'duration': ['Enter a whole number.']} + ] + } + + serializer = self.AlbumSerializer(data=data) + self.assertEqual(serializer.is_valid(), False) + self.assertEqual(serializer.errors, expected_errors) + + def test_many_nested_validation_error(self): + """ + Incorrect nested serialization should return appropriate error data + when multiple entities are being deserialized. + """ + + data = [ + { + 'album_name': 'Russian Red', + 'artist': 'I Love Your Glasses', + 'tracks': [ + {'order': 1, 'title': 'Cigarettes', 'duration': 121}, + {'order': 2, 'title': 'No Past Land', 'duration': 198}, + {'order': 3, 'title': 'They Don\'t Believe', 'duration': 191} + ] + }, + { + 'album_name': 'Discovery', + 'artist': 'Daft Punk', + 'tracks': [ + {'order': 1, 'title': 'One More Time', 'duration': 235}, + {'order': 2, 'title': 'Aerodynamic', 'duration': 184}, + {'order': 3, 'title': 'Digital Love', 'duration': 'foobar'} + ] + } + ] + expected_errors = [ + {}, + { + 'tracks': [ + {}, + {}, + {'duration': ['Enter a whole number.']} + ] + } + ] + + serializer = self.AlbumSerializer(data=data) + self.assertEqual(serializer.is_valid(), False) + self.assertEqual(serializer.errors, expected_errors) + + +class WritableNestedSerializerObjectTests(TestCase): + """ + Tests for deserializing nested entities. + These tests use serializers that restore to concrete objects. + """ + + def setUp(self): + # Couple of concrete objects that we're going to deserialize into + class Track(object): + def __init__(self, order, title, duration): + self.order, self.title, self.duration = order, title, duration + + def __eq__(self, other): + return ( + self.order == other.order and + self.title == other.title and + self.duration == other.duration + ) + + class Album(object): + def __init__(self, album_name, artist, tracks): + self.album_name, self.artist, self.tracks = album_name, artist, tracks + + def __eq__(self, other): + return ( + self.album_name == other.album_name and + self.artist == other.artist and + self.tracks == other.tracks + ) + + # And their corresponding serializers + class TrackSerializer(serializers.Serializer): + order = serializers.IntegerField() + title = serializers.CharField(max_length=100) + duration = serializers.IntegerField() + + def restore_object(self, attrs, instance=None): + return Track(attrs['order'], attrs['title'], attrs['duration']) + + class AlbumSerializer(serializers.Serializer): + album_name = serializers.CharField(max_length=100) + artist = serializers.CharField(max_length=100) + tracks = TrackSerializer(many=True) + + def restore_object(self, attrs, instance=None): + return Album(attrs['album_name'], attrs['artist'], attrs['tracks']) + + self.Album, self.Track = Album, Track + self.AlbumSerializer = AlbumSerializer + + def test_nested_validation_success(self): + """ + Correct nested serialization should return a restored object + that corresponds to the input data. + """ + + data = { + 'album_name': 'Discovery', + 'artist': 'Daft Punk', + 'tracks': [ + {'order': 1, 'title': 'One More Time', 'duration': 235}, + {'order': 2, 'title': 'Aerodynamic', 'duration': 184}, + {'order': 3, 'title': 'Digital Love', 'duration': 239} + ] + } + expected_object = self.Album( + album_name='Discovery', + artist='Daft Punk', + tracks=[ + self.Track(order=1, title='One More Time', duration=235), + self.Track(order=2, title='Aerodynamic', duration=184), + self.Track(order=3, title='Digital Love', duration=239), + ] + ) + + serializer = self.AlbumSerializer(data=data) + self.assertEqual(serializer.is_valid(), True) + self.assertEqual(serializer.object, expected_object) + + def test_many_nested_validation_success(self): + """ + Correct nested serialization should return multiple restored objects + that corresponds to the input data when multiple objects are + being deserialized. + """ + + data = [ + { + 'album_name': 'Russian Red', + 'artist': 'I Love Your Glasses', + 'tracks': [ + {'order': 1, 'title': 'Cigarettes', 'duration': 121}, + {'order': 2, 'title': 'No Past Land', 'duration': 198}, + {'order': 3, 'title': 'They Don\'t Believe', 'duration': 191} + ] + }, + { + 'album_name': 'Discovery', + 'artist': 'Daft Punk', + 'tracks': [ + {'order': 1, 'title': 'One More Time', 'duration': 235}, + {'order': 2, 'title': 'Aerodynamic', 'duration': 184}, + {'order': 3, 'title': 'Digital Love', 'duration': 239} + ] + } + ] + expected_object = [ + self.Album( + album_name='Russian Red', + artist='I Love Your Glasses', + tracks=[ + self.Track(order=1, title='Cigarettes', duration=121), + self.Track(order=2, title='No Past Land', duration=198), + self.Track(order=3, title='They Don\'t Believe', duration=191), + ] + ), + self.Album( + album_name='Discovery', + artist='Daft Punk', + tracks=[ + self.Track(order=1, title='One More Time', duration=235), + self.Track(order=2, title='Aerodynamic', duration=184), + self.Track(order=3, title='Digital Love', duration=239), + ] + ) + ] + + serializer = self.AlbumSerializer(data=data) + self.assertEqual(serializer.is_valid(), True) + self.assertEqual(serializer.object, expected_object)