fix: return unsupported task type when no task_type match

Signed-off-by: habeck <habeck@us.ibm.com>

Author: tedhabeck

cpex/framework/isolated/worker.py

@@ -142,6 +142,11 @@ async def process_task(task_data, tp: TaskProcessor):
             violations_as_exceptions=False,
         )
         return result
+    return {
+        "status": "error",
+        "message": "task type not supported.",
+        "request_id": task_data.get("request_id", "unknown") if "task_data" in locals() else "unknown",
+    }
 
 
 async def main():
@@ -179,7 +184,7 @@ async def main():
                 # Serialize response
                 if response:
                     serializable_response = response.model_dump(mode="json")
-                else:
+                else:  # none case should be a failure rather than success.
                     serializable_response = {"status": "success"}
 
                 # Add request_id to response

tests/unit/cpex/framework/isolated/test_worker.py

@@ -245,7 +245,7 @@ async def test_process_task_unknown_task_type(self):
         tp = TaskProcessor()
         # Should return None or handle gracefully
         result = await process_task(task_data, tp)
-        assert result is None
+        assert result == {'message': 'task type not supported.', 'request_id': 'unknown', 'status': 'error'}
 
     @pytest.mark.asyncio
     @patch("cpex.framework.isolated.worker.get_proper_config")