fix: use custom serializers for custom sequence values

Author: heitorlessa

aws_lambda_powertools/event_handler/openapi/encoders.py

@@ -130,6 +130,7 @@ def jsonable_encoder(  # noqa: PLR0911
                 exclude_none=exclude_none,
                 exclude_defaults=exclude_defaults,
                 exclude_unset=exclude_unset,
+                custom_serializer=custom_serializer,
             )
 
         # Other types
@@ -209,7 +210,8 @@ def _dump_dict(
 
     Parameters
     ----------
-    custom_serializer
+    custom_serializer : Callable, optional
+        A custom serializer to use for encoding the object, when everything else fails.
     """
     encoded_dict = {}
     allowed_keys = set(obj.keys())
@@ -250,9 +252,10 @@ def _dump_sequence(
     exclude_unset: bool = False,
     exclude_none: bool = False,
     exclude_defaults: bool = False,
+    custom_serializer: Optional[Callable[[Any], str]] = None,
 ) -> List[Any]:
     """
-    Dump a sequence to a list, using the same parameters as jsonable_encoder
+    Dump a sequence to a list, using the same parameters as jsonable_encoder.
     """
     encoded_list = []
     for item in obj:
@@ -265,6 +268,7 @@ def _dump_sequence(
                 exclude_unset=exclude_unset,
                 exclude_defaults=exclude_defaults,
                 exclude_none=exclude_none,
+                custom_serializer=custom_serializer,
             ),
         )
     return encoded_list

tests/functional/event_handler/_pydantic/test_openapi_encoders.py

@@ -197,8 +197,7 @@ class MyClass:
 
 def test_openapi_encode_custom_serializer_nested_dict():
     # GIVEN a nested dictionary with a custom class
-    class CustomClass(object):
-        __slots__ = []
+    class CustomClass: ...
 
     nested_dict = {"a": {"b": CustomClass()}}
 
@@ -211,3 +210,21 @@ def serializer(value):
 
     # THEN we should get the custom serializer output
     assert result == {"a": {"b": "serialized"}}
+
+
+def test_openapi_encode_custom_serializer_sequences():
+    # GIVEN a sequence with a custom class
+    class CustomClass:
+        __slots__ = []
+
+    seq = [CustomClass()]
+
+    # AND a custom serializer
+    def serializer(value):
+        return "serialized"
+
+    # WHEN we call jsonable_encoder with the nested dictionary and unserializable value
+    result = jsonable_encoder(seq, custom_serializer=serializer)
+
+    # THEN we should get the custom serializer output
+    assert result == ["serialized"]