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 out

Answer 1

$BUILD_CAUSE env is not available for pipelines, and in multibranch pipeline even currentBuild.rawBuild.getCause(hudson.model.Cause$UserIdCause) would fail, if build was triggered by SCM change or timer. So, I implemented below workaround..

    def manualTrigger = false
    node('master'){
       def causes = currentBuild.rawBuild.getCauses()
       for(cause in causes) {
          if(cause.properties.shortDescription =~ 'Started by user') {
             manualTrigger = true
             break
          }
      }
  }

And rest of my workflow is in another node

   node('nodefarm') {
       if(manualTrigger) {
         // do build stuff here
       } else {
         //build not triggered by user.
       }
   }