How to compensate task failures

[marcolenzo]

This is more of a support request than an issue.

I was wondering what is the proper way of compensating task failures.

Let's assume that I have a provisioning flows which involves two steps in series. However if the second step in the flow fails, I need to revert whatever I did in the first step. How am I supposed to do that?

From what I am understanding I cannot use a DECISION task. The only option at hand seems to use Events and EventHandlers. Can someone guide me in the right direction?

[v1r3n]

@marcolenzo there are two ways you can do this.

• Mark the task as optional and let a decision task ( ${taskRef.status} ) take care of handling compensation.
• Keep the task as it is and let the workflow fail. Add a failure handler workflow (https://github.com/Netflix/conductor/blob/master/common/src/main/java/com/netflix/conductor/common/metadata/workflow/WorkflowDef.java#L48) to be executed when the workflow fails. Add the logic for compensation in this failure handler workflow.

[marcolenzo]

@v1r3n thank you for the prompt support!

[marcolenzo]

@v1r3n I am re-opening the issue because I have some additional questions after I had chance to try out your suggestions.

1- It does not seem possible to specify the version of the failureWorkflow. I noticed that the failureWorkflow shares the input of the original workflow, thus the version as well. Is it intentional? 2- Is there a way to access the output of the original workflow?

[v1r3n]

1. This is a known limitation that failure workflow does not allow specifying the version. We are adding that in the coming releases. (no ETA as yet)
2. Failure workflow should get the output of main workflow that failed as input. Again, not in the current release, but we will add in the coming releases.