Run job on all existing Jenkins workers

Question

I have a Job in a pipeline that cleans up docker images. It runs the job on each worker individually. This is frustrating because when I add jenkins-cpu-worker3, I'll have to update this job. I'd like to run this job in such a way that it runs on all workers without having to update it each time a new worker is present. I also want the job to be able to run regardless of what I name each worker. It needs to run on all workers no matter what. Is there a way to query jenkins from within the pipeline to get me a list or array of all the workers that exist. I was leafing through documentation and posts online and I have not found a solution that works. If possible I'd like to do this without any additional Jenkins Plugins.

pipeline {
  agent any

  stages {

    stage('Cleanup jenkins-cpu-worker1') {
      agent {
        node {
          label 'jenkins-cpu-worker1'
        }
      }

      steps {
        sh "docker container prune -f"
        sh "docker image prune -f"
        sh '''docker images | awk '{print $1 ":" $2}' | xargs docker image rm || true'''
        sh "docker network prune -f"
        sh "docker volume prune -f"
      }
    }

    stage('Cleanup jenkins-cpu-worker2') {
      agent {
        node {
          label 'jenkins-cpu-worker2'
        }
      }

      steps {
        sh "docker container prune -f"
        sh "docker image prune -f"
        sh '''docker images | awk '{print $1 ":" $2}' | xargs docker image rm || true'''
        sh "docker network prune -f"
        sh "docker volume prune -f"
      }
    }

Answer 1

Here is an improved version of your Pipeline. This will dynamically get all the active agents, and run your cleanup task in parallel.

pipeline {
    agent any

    stages {
        stage('CleanupWorkers') {
            steps {
                script {
                    echo "Something"
                    parallel parallelJobs()
                }
            }
        }
    }
}

def parallelJobs() {
  jobs = [:]
  for (def nodeName in getAllNodes()) {
    jobs[nodeName] = getStage(nodeName)
  }
  return jobs
}

def getStage(def nodeName){
    return { 
        stage("Cleaning $nodeName") {
           node(nodeName){
                sh'''
                  echo "Srating cleaning"
                  docker container prune -f
                  docker image prune -f
                  docker images | awk '{print $1 ":" $2}' | xargs docker image rm || true
                  docker network prune -f
                  docker volume prune -f
                '''
           }
         }
    }
}

def getAllNodes() {
    def nodeNames = [] 
    def jenkinsNodes = Jenkins.instance.getNodes().each { node ->
    // Ignore offline agents
    if (!node.getComputer().isOffline()){
      nodeNames.add(node.getNodeName())
    } 
  }
  return nodeNames
}