If Enum column is also subclass of str use default JSON serialization

CHANGES

@@ -4,7 +4,12 @@ Changelog
 Changes in Flask-Restless-NG
 ============================
 
-Version 3.2.0
+Version 3.2.0 (2024-01-19)
+-------------
+- If Enum column is also subclass of `str` use default JSON serialization
+
+
+Version 3.2.0 (2024-01-19)
 -------------
 - Dropped savalidation support
 - Added a parameter to serializer to skip primary key check (not recommended)

flask_restless/__init__.py

@@ -13,7 +13,7 @@
 
 """
 #: The current version of this extension.
-__version__ = '3.2.0'
+__version__ = '3.2.1'
 
 
 # The following names are available as part of the public API for Flask-Restless-NG.

flask_restless/serialization.py

@@ -431,7 +431,7 @@ def serialize_attributes(self, instance, only=None) -> Dict[str, Any]:
             elif isinstance(value, timedelta):
                 attributes[key] = value.total_seconds()
             # Enums are not serializable by default, use 'name' property
-            elif isinstance(value, enum.Enum):
+            elif isinstance(value, enum.Enum) and not isinstance(value, str):
                 attributes[key] = value.name
 
         return attributes

tests/test_serializer.py

@@ -37,6 +37,11 @@ class MyEnum(enum.Enum):
     three = 3
 
 
+class MyEnumStr(str, enum.Enum):
+    one = "One"
+    two = "Two"
+
+
 class Model(Base):
     __tablename__ = 'article'
     id = Column(Integer, primary_key=True)
@@ -51,6 +56,7 @@ class Model(Base):
     interval_field = Column(Interval())
     time_field = Column(Time())
     enum_field = Column(Enum(MyEnum))
+    enum_str_field = Column(Enum(MyEnumStr))
 
 
 def test_serialize_attributes():
@@ -67,7 +73,8 @@ def test_serialize_attributes():
         datetime_field=datetime.datetime(year=2021, month=1, day=1, hour=12, minute=0, second=0),
         time_field=datetime.time(12, 0, 0),
         interval_field=datetime.timedelta(minutes=1),
-        enum_field=MyEnum.two
+        enum_field=MyEnum.two,
+        enum_str_field=MyEnumStr.one
     )
 
     serialized = serializer.serialize_attributes(instance)
@@ -85,7 +92,8 @@ def test_serialize_attributes():
         'datetime_field': '2021-01-01T12:00:00',
         'time_field': '12:00:00',
         'interval_field': 60.0,
-        'enum_field': 'two'
+        'enum_field': 'two',
+        'enum_str_field': 'One',
     }