how to get $CAUSE in workflow

Question

Jenkins has a $CAUSE variable available to freestyle build jobs.

How can I access this or something similar in workflow?

My team makes use of it in email output of existing ad-hoc builds. We'd like to continue the same in new workflow based jobs.

Answer 1

It looks like Workflow builds don't have this variable injected. However you can retrieve the required info from currentBuild.rawBuild object using hudson.model.Run.getCause() or hudson.model.Run.getCauses() method.

Example:

Workflow script:

println "CAUSE ${currentBuild.rawBuild.getCause(hudson.model.Cause$UserIdCause).properties}" 

results with this output:

Running: Print Message CAUSE [userName:John Smith, userId:jsmith, class:class hudson.model.Cause$UserIdCause, shortDescription:Started by user John Smith] 

Other Cause subtypes can be found in the javadoc.

There is also a good get-build-cause example which is based on this answer in the jenkins Pipeline Examples repository.