[BUG] Error Message is not being logged when exception is thrown by BPMN Error

[sowmyahl21]

Environment

Description

When a exception is thrown by BPMN Error, the associated error message is not being logged along with the status code BpmnBehaviorLogger.java This makes it difficult to diagnose the root cause of the error as only status code will be logged when an exception is thrown. We can see the same in the below attached screenshot

Steps to reproduce

Create a sample model which throws BPMN Error and observe that the error code is captured but the error message is not available.

Observed Behavior

Currently, when the BPMN error is thrown, the error code is captured but the error message is not available. We can see the same in the above attached screenshot.

Expected behavior

When the exception is thrown by BPMN error, it would be helpful to log the error message along with the error code which helps for easier debugging.

Root Cause

Solution Ideas

Update the exception message in BpmnBehaviorLogger to display the error message along with other parameters.

These files may have to be modified https://github.com/camunda/camunda-bpm-platform/blob/master/engine/src/main/java/org/camunda/bpm/engine/impl/bpmn/behavior/BpmnBehaviorLogger.java

https://github.com/camunda/camunda-bpm-platform/blob/master/engine/src/main/java/org/camunda/bpm/engine/impl/bpmn/helper/BpmnExceptionHandler.java

Hints

Links

Breakdown

### Pull Requests

Dev2QA handover

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[sowmyahl21]

I'm interested to work on the fix. Please let me know if there are any concerns

[mboskamp]

Hi @sowmyahl21, thank you for raising a bug report. It's awesome to hear that you want to contribute a fix.

I have some questions before we commit to changing the behavior:

• Can you share more details on how to reproduce the problem? Maybe you can share a failing BPMN.
• Can you outline what your solution proposal would look like?
  • The exception you showed in the screenshot originates from the missingBoundaryCatchEventError method. There is a similar method that could benefit from the same improvement: missingBoundaryCatchEvent. Those two methods are very similar. Based on a process engine config flag, one of the two methods is used to log the message or throw an exception.
• We should add tests to ensure that the error message is added to the log/exception.
  • Here is one example how it could be done when throwing the exception is enabled via process engine flag.
  • When the flag is not enabled and the message is only logged, we can use ProcessEngineLoggingRule to make assert the log output.
• Is this really a bug? What exactly do you think is broken? I understand you want to add the error message of a custom BPMN error to the log output.
  • I would argue that the error message will be available when there is an error handler to process it. The message you see now is caused by the error not being propagated correctly (due to the missing handler). The error code (and potentially the message) should only help to identify which part of the BPMN to fix, correct?
  • Can we change the type of the issue to feature?