Log a warning if duplicate worklist item detected

src/services/mwl/create_worklist_item.py

@@ -1,6 +1,6 @@
 import logging
 
-from services.storage import MWLStorage, WorklistItem
+from services.storage import DuplicateWorklistItemError, MWLStorage, WorklistItem
 
 logger = logging.getLogger(__name__)
 
@@ -38,6 +38,11 @@ def call(self, payload: dict):
             )
             logger.info(f"Created worklist item: {item.get('accession_number')}")
             return {"status": "created", "action_id": action_id}
+        except DuplicateWorklistItemError:
+            logger.warning(
+                f"Duplicate worklist item ignored: accession_number={item.get('accession_number')!r}, action_id={action_id!r}"
+            )
+            return {"status": "duplicate", "action_id": action_id}
         except Exception as e:
             logger.error(f"Failed to create worklist item: {e}")
             return {"status": "error", "action_id": action_id, "error": str(e)}

src/services/storage.py

@@ -309,6 +309,12 @@ class WorklistItemNotFoundError(Exception):
     pass
 
 
+class DuplicateWorklistItemError(Exception):
+    """Raised when a worklist item with the same accession number already exists."""
+
+    pass
+
+
 class MWLStorage(Storage):
     def __init__(self, db_path: str = "/var/lib/pacs/worklist.db"):
         """
@@ -336,20 +342,23 @@ def store_worklist_item(
         Raises:
             sqlite3.IntegrityError: If accession number already exists
         """
-        with self._get_connection() as conn:
-            conn.execute(
-                (
-                    "INSERT INTO worklist_items (accession_number, modality, patient_birth_date, "
-                    "patient_id, patient_name, patient_sex, procedure_code, scheduled_date, "
-                    "scheduled_time, source_message_id, study_description, study_instance_uid) "
-                    "VALUES (:accession_number, :modality, :patient_birth_date, "
-                    ":patient_id, :patient_name, :patient_sex, :procedure_code, "
-                    ":scheduled_date, :scheduled_time, :source_message_id, "
-                    ":study_description, :study_instance_uid)"
-                ),
-                worklist_item.__dict__,
-            )
-            conn.commit()
+        try:
+            with self._get_connection() as conn:
+                conn.execute(
+                    (
+                        "INSERT INTO worklist_items (accession_number, modality, patient_birth_date, "
+                        "patient_id, patient_name, patient_sex, procedure_code, scheduled_date, "
+                        "scheduled_time, source_message_id, study_description, study_instance_uid) "
+                        "VALUES (:accession_number, :modality, :patient_birth_date, "
+                        ":patient_id, :patient_name, :patient_sex, :procedure_code, "
+                        ":scheduled_date, :scheduled_time, :source_message_id, "
+                        ":study_description, :study_instance_uid)"
+                    ),
+                    worklist_item.__dict__,
+                )
+                conn.commit()
+        except sqlite3.IntegrityError:
+            raise DuplicateWorklistItemError(f"Worklist item already exists: {worklist_item.accession_number}")
 
         return worklist_item.accession_number
 

tests/services/mwl/test_create_worklist_item.py

@@ -1,7 +1,7 @@
 from unittest.mock import patch
 
 from services.mwl.create_worklist_item import CreateWorklistItem
-from services.storage import WorklistItem
+from services.storage import DuplicateWorklistItemError, WorklistItem
 
 
 @patch(f"{CreateWorklistItem.__module__}.MWLStorage")
@@ -40,6 +40,18 @@ def test_call_missing_action_id(self, mock_mwl_storage, listener_payload):
 
         mock_storage_instance.store_worklist_item.assert_not_called()
 
+    def test_call_duplicate_worklist_item(self, mock_mwl_storage, listener_payload):
+        mock_storage_instance = mock_mwl_storage.return_value
+        mock_storage_instance.store_worklist_item.side_effect = DuplicateWorklistItemError(
+            "Worklist item already exists: ACC999999"
+        )
+        subject = CreateWorklistItem(mock_storage_instance)
+
+        response = subject.call(listener_payload)
+        assert response == {"status": "duplicate", "action_id": "action-12345"}
+
+        mock_storage_instance.store_worklist_item.assert_called_once()
+
     def test_call_storage_exception(self, mock_mwl_storage, listener_payload):
         mock_storage_instance = mock_mwl_storage.return_value
         mock_storage_instance.store_worklist_item.side_effect = Exception("DB error")