Tag Archives: CI

Override Jenkins stage Function

Recently, I needed a mechanism to identify, as part of a try/catch block, which stage in a Jenkins Groovy Scripted Pipeline was the last to execute before the catch block was called.

Jenkins does not currently store details about the last stage to run outside of the context of that specific stage. So, in other words env.STAGE_NAME is valid with a particular stage("I'm a stage"){ //valid here} block, but not in, say, a catch(Exception e) { // where was I called from? } block.

To get around this, I found a few examples, and cobbled together something that I believe will provide future functionality. I present to you the extensibleContextStage:

// Jenkins groovy stages are somewhat lacking in their ability to persist 
// context state beyond the lifespan of the stage
// For example, to obtain the name of the last stage to run, 
// one needs to store the name in an ENV varialble (JENKINS 48315)
// https://issues.jenkins-ci.org/browse/JENKINS-48315

// We can create an extensible stage to provide attitional context to the pipeline
// about the state of the currently running stage.

// This also provides a capability to extend pre- and post- stage operations

// Idea / base code borrowed from https://stackoverflow.com/a/51081177/11125318
// and from https://issues.jenkins-ci.org/browse/JENKINS-48315?focusedCommentId=321366&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-321366

def call(name, Closure closure) {
    try {
        stage(name) {
            def result = closure.call()
            return result
    catch(Exception ex) {
        env.BUILD_LAST_STAGE_FAILED = name
        throw ex;

This is a drop-in replacement for stage(string name){ closure} blocks in a Jenkins Groovy Scripted Pipeline, but with the added benefit of additional environment variables:


So, as a full example, one can now do this (which was previously awkward):

try {
    extensibleContextStage("Do some things")
    extensibleContextStage("Do some More things")
       throw new Exception("MAYHEM!")
    extensibleContextStage("Do some final things")
catch(Exception e){
    // at this point, with normal stage, we wouldn't know where MAYHEM came from,
    // but with extensibleContextStage, we can look at either
    // to know that "Do some More things" was the offendign stage.
    // this is super handy to send "helpful" notifications to slack/email

I hope this helps someone (if even my future self)

Obtaining Git Repo URL from Jenkins Changeset: Unsolved

I’m attempting to obtain a Git Repo URL from a Jenkins Change set in a Groovy Scripted Pipeline, but I keep running into the same issue: the browser property (obtained via .getBrowser()) on my hudson.plugins.git.GitChangeSetList object is undefined.

I’m running the below code (with inline “status comments”) from the Jenkins groovy script console in an attempt to extract the RepoUrl from Chagesets in a Jenkins Multi branch groovy scripted pipeline:

def job = Jenkins.instance.getItem("MyJenkinsJob") 
def branch = job.getItems().findAll({ 
            item -> item.getDisplayName().contains("Project/CreateChangeLogs")

printAllMethods(branch[0].getFirstBuild()) //this works, and is a org.jenkinsci.plugins.workflow.job.WorkflowRun

def builds = branch[0].getBuilds()
def currentBuild = builds[0]

currentBuild.changeSets.collect { 
  printAllMethods(it) // this works too, and is a hudson.plugins.git.GitChangeSetList.
  // enumerated methods are equals(); getClass(); hashCode(); notify(); notifyAll(); toString(); wait(); createEmpty(); getBrowser(); getItems(); getKind(); getRun(); isEmptySet(); getLogs(); iterator(); 

  it.getBrowser().repoUrl // this fails
  // the error is java.lang.NullPointerException: Cannot get property 'repoUrl' on null object

I found the utility class for PrintAllMethods here (https://bateru.com/news/2011/11/code-of-the-day-groovy-print-all-methods-of-an-object/):

  void printAllMethods( obj ){
    if( !obj ){
        println( "Object is null\r\n" );
    if( !obj.metaClass && obj.getClass() ){
        printAllMethods( obj.getClass() );
    def str = "class ${obj.getClass().name} functions:\r\n";
        str += it+"(); "; 
    println "${str}\r\n";

The API spec for GitChangeSetList indicates that in extends hudson.scm.ChangeLogSet which implements getBrowser(), so the call should be valid.

Additionally, the source for GitChangeSetList invokes the super() constructor with the passed browser object.

At this point, I’m probably going to continue diving through the source code until I figure it out.

It looks like this is a documented issue with Jenkins: https://issues.jenkins-ci.org/browse/JENKINS-52747

And a (somewhat) related StackOverflow post: https://devops.stackexchange.com/questions/3798/determine-the-url-for-a-scm-trigger-from-inside-the-build