fix(testing-sdk): serialization for callback fail accepts empty bodies (#99)

Author: bchampp

src/aws_durable_execution_sdk_python_testing/web/handlers.py

@@ -91,11 +91,27 @@ def _parse_json_body(self, request: HTTPRequest) -> dict[str, Any]:
             dict: The parsed JSON data
 
         Raises:
-            InvalidParameterValueException: If the request body is empty or invalid JSON
+            InvalidParameterValueException: If the request body is empty
         """
         if not request.body:
             msg = "Request body is required"
             raise InvalidParameterValueException(msg)
+        return self._parse_json_body_optional(request)
+
+    def _parse_json_body_optional(self, request: HTTPRequest) -> dict[str, Any]:
+        """Parse JSON body from HTTP request with validation.
+
+        Args:
+            request: The HTTP request containing the JSON body
+
+        Returns:
+            dict: The parsed JSON data
+
+        Raises:
+            InvalidParameterValueException: If the request body is invalid JSON
+        """
+        if not request.body:
+            return {}
 
         # Handle both dict and bytes body types
         if isinstance(request.body, dict):
@@ -690,7 +706,7 @@ def handle(self, parsed_route: Route, request: HTTPRequest) -> HTTPResponse:
             callback_route = cast(CallbackFailureRoute, parsed_route)
             callback_id: str = callback_route.callback_id
 
-            body_data: dict[str, Any] = self._parse_json_body(request)
+            body_data: dict[str, Any] = self._parse_json_body_optional(request)
             callback_request: SendDurableExecutionCallbackFailureRequest = (
                 SendDurableExecutionCallbackFailureRequest.from_dict(
                     body_data, callback_id
@@ -734,10 +750,7 @@ def handle(self, parsed_route: Route, request: HTTPRequest) -> HTTPResponse:
             HTTPResponse: The HTTP response to send to the client
         """
         try:
-            # Parse request body for validation but heartbeat doesn't use the data
-            body_data: dict[str, Any] = self._parse_json_body(request)
-            SendDurableExecutionCallbackHeartbeatRequest.from_dict(body_data)
-
+            # Heartbeat requests don't have a body, only callback_id from URL
             callback_route = cast(CallbackHeartbeatRoute, parsed_route)
             callback_id: str = callback_route.callback_id
 

tests/web/handlers_test.py

@@ -2173,10 +2173,8 @@ def test_send_durable_execution_callback_failure_handler_empty_body():
     )
 
     response = handler.handle(callback_route, request)
-    # Handler returns 400 for empty body with AWS-compliant format
-    assert response.status_code == 400
-    assert response.body["Type"] == "InvalidParameterValueException"
-    assert "Request body is required" in response.body["message"]
+    # Handler should accept empty body for failure requests
+    assert response.status_code == 200
 
 
 def test_send_durable_execution_callback_heartbeat_handler():
@@ -2221,24 +2219,22 @@ def test_send_durable_execution_callback_heartbeat_handler_empty_body():
     executor = Mock()
     handler = SendDurableExecutionCallbackHeartbeatHandler(executor)
 
+    base_route = Route.from_string(
+        "/2025-12-01/durable-execution-callbacks/test-id/heartbeat"
+    )
+    callback_route = CallbackHeartbeatRoute.from_route(base_route)
+
     request = HTTPRequest(
         method="POST",
-        path=Route.from_string(
-            "/2025-12-01/durable-execution-callbacks/test-id/heartbeat"
-        ),
+        path=callback_route,
         headers={},
         query_params={},
         body={},
     )
 
-    response = handler.handle(
-        Route.from_string("/2025-12-01/durable-execution-callbacks/test-id/heartbeat"),
-        request,
-    )
-    # Handler returns 400 for empty body with AWS-compliant format
-    assert response.status_code == 400
-    assert response.body["Type"] == "InvalidParameterValueException"
-    assert "Request body is required" in response.body["message"]
+    response = handler.handle(callback_route, request)
+    # Handler should accept empty body for heartbeat requests
+    assert response.status_code == 200
 
 
 def test_health_handler():