Merge 518f6ebb57 into f7917928c0

rest_framework/relations.py

@@ -320,6 +320,24 @@ class SlugRelatedField(RelatedField):
         return getattr(obj, self.slug_field)
 
 
+class MultipleSlugRelatedField(SlugRelatedField):
+    def __init__(self, separator=None, **kwargs):
+        assert separator is not None, 'The `separator` argument is required.'
+        self.separator = separator
+        super(MultipleSlugRelatedField, self).__init__(**kwargs)
+
+    def to_internal_value(self, data):
+        try:
+            return self.get_queryset().get(**dict(zip(self.slug_field, data.split(self.separator, len(self.slug_field)))))
+        except ObjectDoesNotExist:
+            self.fail('does_not_exist', slug_name=self.slug_field, value=smart_text(data))
+        except (TypeError, ValueError, AttributeError):
+            self.fail('invalid')
+
+    def to_representation(self, obj):
+        return six.text_type(obj)
+
+
 class ManyRelatedField(Field):
     """
     Relationships with `many=True` transparently get coerced into instead being

tests/test_relations.py

@@ -1,3 +1,4 @@
+import six
 from .utils import mock_reverse, fail_reverse, BadType, MockObject, MockQueryset
 from django.core.exceptions import ImproperlyConfigured
 from django.utils.datastructures import MultiValueDict
@@ -138,6 +139,40 @@ class TestSlugRelatedField(APISimpleTestCase):
         assert representation == self.instance.name
 
 
+class TestMultipleSlugRelatedField(APISimpleTestCase):
+    def setUp(self):
+        self.queryset = MockQueryset([
+            MockObject(pk=1, name='foo', code='hamster'),
+            MockObject(pk=2, name='bar', code='bazinga'),
+            MockObject(pk=3, name='bar', code='cheeseshop')
+        ])
+        self.instance = self.queryset.items[2]
+        self.field = serializers.MultipleSlugRelatedField(
+            slug_field=('name', 'code'), queryset=self.queryset, separator='-'
+        )
+
+    def test_slug_related_lookup_exists(self):
+        data = '{}-{}'.format(self.instance.name, self.instance.code)
+        instance = self.field.to_internal_value(data)
+        assert instance is self.instance
+
+    def test_slug_related_lookup_does_not_exist(self):
+        with pytest.raises(serializers.ValidationError) as excinfo:
+            self.field.to_internal_value('doesnotexist')
+        msg = excinfo.value.detail[0]
+        assert msg == 'Object with (\'name\', \'code\')=doesnotexist does not exist.'
+
+    def test_slug_related_lookup_invalid_type(self):
+        with pytest.raises(serializers.ValidationError) as excinfo:
+            self.field.to_internal_value(BadType())
+        msg = excinfo.value.detail[0]
+        assert msg == 'Invalid value.'
+
+    def test_representation(self):
+        representation = self.field.to_representation(self.instance)
+        assert representation == six.text_type(self.instance)
+
+
 class TestManyRelatedField(APISimpleTestCase):
     def setUp(self):
         self.instance = MockObject(pk=1, name='foo')