pipeline {
  agent any
  stages {
    stage('Build image') {
      steps {
        withDockerRegistry([ credentialsId: "6ff44976-23cd-4cc2-902c-de8c340e65e5", url: "https://reg.zknt.org" ]) {
          echo 'Starting to build docker image'
          script {
            def customImage = docker.build("reg.zknt.org/zknt/alpine:3.8.1")
            customImage.push()
          }
        }
      }
    }
  }
}