Add support for source with attributes in extra_kwargs of ModelSerializer

rest_framework/serializers.py

@@ -1117,9 +1117,36 @@ def get_fields(self):
  if source == '*':
  source = field_name
 
+ # Get the right model and info for source with attributes
+ source_attrs = source.split('.')
+ source_info = info
+ source_model = model
+
+ if len(source_attrs) > 1:
+ attr_info = info
+ attr_model = model
+
+ for attr in source_attrs[:-1]:
+ if attr not in attr_info.relations:
+ break
+
+ attr_model = attr_info.relations[attr].related_model
+ attr_info = model_meta.get_field_info(attr_model)
+ else:
+ attr = source_attrs[-1]
+ if (
+ attr in attr_info.fields_and_pk
+ or attr in attr_info.relations
+ or hasattr(attr_model, attr)
+ or attr == self.url_field_name
+ ):
+ source = attr
+ source_info = attr_info
+ source_model = attr_model
+
  # Determine the serializer field class and keyword arguments.
  field_class, field_kwargs = self.build_field(
- source, info, model, depth
+ source, source_info, source_model, depth
  )
 
  # Include any kwargs defined in `Meta.extra_kwargs`

tests/test_model_serializer.py

@@ -735,6 +735,27 @@ class Meta:
  """)
  self.assertEqual(repr(TestSerializer()), expected)
 
+ def test_source_with_attributes(self):
+ class TestSerializer(serializers.ModelSerializer):
+ class Meta:
+ model = RelationalModel
+ fields = ('foreign_key_name', 'one_to_one_name')
+ extra_kwargs = {
+ 'foreign_key_name': {
+ 'source': 'foreign_key.name',
+ },
+ 'one_to_one_name': {
+ 'source': 'one_to_one.name',
+ }
+ }
+
+ expected = dedent("""
+ TestSerializer():
+ foreign_key_name = CharField(max_length=100, source='foreign_key.name')
+ one_to_one_name = CharField(max_length=100, source='one_to_one.name')
+ """)
+ self.assertEqual(repr(TestSerializer()), expected)
+
 
 class DisplayValueTargetModel(models.Model):
  name = models.CharField(max_length=100)