issue #7338 : Pipeline fails to open error-handling hop

[mattcasters]

Walkthrough - XML Deserialization Lookup Graceful Failure (Issue 7338)

We fixed an issue where loading a pipeline XML file failed with a fatal exception if an error-handling configuration referenced a target transform name that no longer exists in the pipeline (or was deleted). We changed the deserialization process to handle missing references gracefully.

Changes Made

Core Metadata Serialization

• Modified XmlMetadataUtil.java:
  • In deSerializeXmlUsingNamedList(...), removed the throwing of HopXmlException when a referenced object name (e.g., in a named list such as transforms or workflowActions) cannot be found.
  • Instead, the method now returns null, allowing the deserialization of the parent object to finish successfully, setting the missing reference field to null.

Core Engine Tests

• Added a new unit test testIssue7338() to PipelineMetaTest.java:
  • Defines an XML pipeline with an error handling block that points to a non-existent transform NonExistentTransform.
  • Asserts that parsing this XML completes successfully, the pipeline is loaded, and the target transform field resolves to null without throwing a fatal deserialization error.

Verification & Testing

Compilation & Tests

• Successfully ran Spotless formatting check:

  ./mvnw spotless:check -pl core,engine

• Executed unit tests for core and engine modules, with all 584 tests passing successfully:

  ./mvnw test -pl core,engine

• Executed transform integration tests successfully (exit code 0):

  integration-tests/scripts/run-tests.sh transforms