Functions to get stages executed and build state

build-stages-status.groovy

import hudson.model.Action

import com.cloudbees.workflow.flownode.FlowNodeUtil
import com.cloudbees.workflow.rest.external.StatusExt

import org.jenkinsci.plugins.workflow.graph.FlowNode
import org.jenkinsci.plugins.workflow.cps.nodes.StepStartNode
import org.jenkinsci.plugins.workflow.cps.nodes.StepEndNode
import org.jenkinsci.plugins.workflow.actions.LabelAction


@NonCPS
def convertParameters(parameters) {
    def parametersConverted = new ArrayList<hudson.model.ParameterValue>()
    for (param in parameters) {
        def key = param.key.trim()
        if (param.value instanceof Boolean) {
            parametersConverted.add(new BooleanParameterValue(key.toString(), param.value))
        }
        else {
            parametersConverted.add(new StringParameterValue(key.toString(), param.value.toString()))
        }
    }
    
    return parametersConverted
}

def __flowNodeHasLabelAction(FlowNode flowNode){
    def actions = flowNode.getActions()

    for (Action action: actions){
        if (action instanceof LabelAction) {
            return true
        }
    }

    return false
}

def __getBuildStages(List<FlowNode> flowNodes, data = [startNodes: [], stages: []]) {
    def currentFlowNode = null

    for (FlowNode flowNode: flowNodes){
        currentFlowNode = flowNode
        if (flowNode instanceof StepEndNode) {
		def startNode = flowNode.getStartNode()
		if (__flowNodeHasLabelAction(startNode)) {
			data.startNodes.add(0, startNode)
			data.stages.add(0, [name: startNode.getDisplayName(), status: FlowNodeUtil.getStatus(flowNode)])
		}
        }
	else if(flowNode instanceof StepStartNode && __flowNodeHasLabelAction(flowNode) && !data.startNodes.contains(flowNode)) {
		data.startNodes.add(0, flowNode)
		data.stages.add(0, [name: flowNode.getDisplayName(), status: StatusExt.IN_PROGRESS])
        }
    }

    if (currentFlowNode == null) {
        return data.stages
    }

    return __getBuildStages(currentFlowNode.getParents(), data)
}

def getBuildInformations(build){
    def rawBuild = build.getRawBuild()
    def execution = rawBuild.getExecution()
    def executionHeads = execution.getCurrentHeads()
    def data = [
	status: build.result,
	stages: __getBuildStages(executionHeads)
    ]
    return data
}

def getBuildCurrentStage(build){
    def data = getBuildInformations(build)
    return data.stages.get(data.stages.size() - 1);
}



stage('Stage 1') {
    println "Current build"
    println getBuildInformations(currentBuild)
	
    println "Current build stage"
    println getBuildCurrentStage(currentBuild)
  
    println "Previous build"
    println getBuildInformations(currentBuild.getPreviousBuild())
}

stage('Stage 2') {
    println "Current build"
    println getBuildInformations(currentBuild)
	
    println "Current build stage"
    println getBuildCurrentStage(currentBuild)
	
    def buildOtherPipeline = build job: "Other pipeline", parameters: convertParameters(params), propagate: false
    println "Current build for buildOtherPipeline"
    println getBuildInformations(buildOtherPipeline)
		  
    println "Previous build for buildOtherPipeline"
    println getBuildInformations(buildOtherPipeline.getPreviousBuild())
}

Hey this is great! Question, if a stage fails and causes the build to fail, do you know how to capture the error message say in the post stage?

Please note, you need to disable script sandbox to use this code.