Enhance service bus handling of invalid JSON in receive_message function

CHANGELOG.md

@@ -8,6 +8,9 @@ ENHANCEMENTS:
 * Pin all GitHub Actions workflow steps to full commit SHAs to prevent supply chain attacks plus update to latest releases ([#4886](https://github.com/microsoft/AzureTRE/pull/4886))
 * Add Windows Server 2025 image support to Guacamole. ([#4890](https://github.com/microsoft/AzureTRE/issues/4890))
 
+BUG FIXES:
+* Fix to enhance service bus handling of invalid JSON in receive_message function
+
 ## (0.28.0) (March 2, 2026)
 **BREAKING CHANGES**
 * Sonatype Nexus shared service now requires explicit EULA acceptance (`accept_nexus_eula: true`) when deploying. This ensures compliance with Sonatype Nexus Community Edition licensing. ([#4842](https://github.com/microsoft/AzureTRE/issues/4842))

resource_processor/_version.py

@@ -1 +1 @@
-__version__ = "0.13.3"
+__version__ = "0.13.4"

resource_processor/tests_rp/test_runner.py

@@ -128,6 +128,32 @@ async def test_receive_message(mock_invoke_porter_action, mock_service_bus_clien
     mock_service_bus_client_instance.get_queue_receiver.assert_called_once_with(queue_name="test_queue", max_wait_time=1, session_id=ServiceBusSessionFilter.NEXT_AVAILABLE)
 
 
+@pytest.mark.asyncio
+async def test_receive_message_bad_json(mock_service_bus_client, mock_auto_lock_renewer):
+    mock_service_bus_client_instance = mock_service_bus_client.return_value
+
+    # Set up the lock renewer mock correctly
+    mock_renewer = AsyncMock()
+    mock_renewer.register = Mock()
+    mock_auto_lock_renewer.return_value.__aenter__.return_value = mock_renewer
+
+    mock_receiver = AsyncMock()
+    mock_receiver.__aenter__.return_value = mock_receiver
+    mock_receiver.__aexit__.return_value = None
+    mock_receiver.session.session_id = "test_session_id"
+    mock_receiver.__aiter__.return_value = ["invalid_json_string"]
+
+    mock_service_bus_client_instance.get_queue_receiver.return_value.__aenter__.return_value = mock_receiver
+
+    run_once = Mock(side_effect=[True, False])
+
+    config = {"resource_request_queue": "test_queue"}
+
+    await receive_message(mock_service_bus_client_instance, config, keep_running=run_once)
+    mock_receiver.dead_letter_message.assert_called_once_with("invalid_json_string", reason="InvalidJSON")
+    mock_receiver.complete_message.assert_not_called()
+
+
 @pytest.mark.asyncio
 async def test_receive_message_unknown_exception(mock_auto_lock_renewer, mock_service_bus_client, mock_logger):
     """Test receiving a message with an unknown exception."""

resource_processor/vmss_porter/runner.py

@@ -73,6 +73,8 @@ async def receive_message(service_bus_client, config: dict, keep_running=lambda:
                             message = json.loads(str(msg))
                         except (json.JSONDecodeError) as e:
                             logger.error(f"Received bad service bus resource request message: {e}")
+                            await receiver.dead_letter_message(msg, reason="InvalidJSON")
+                            continue
 
                         with tracer.start_as_current_span("receive_message") as current_span:
                             current_span.set_attribute("resource_id", message["id"])