dind_podtemplate.groovy

// Reference https://github.com/jenkinsci/kubernetes-plugin/blob/master/examples/dind.groovy

/*
“Docker-in-Docker”: runs a Docker-based build where the Docker daemon and client are both defined in the pod.
This allows you to control the exact version of Docker used.
(For example, try DOCKER_BUILDKIT=1 to access advanced Dockerfile syntaxes.)
There is no interaction with the container system used by Kubernetes:
docker.sock does not need to be mounted as in dood.groovy.
May or may not work depending on cluster policy: https://kubernetes.io/docs/concepts/policy/pod-security-policy/
*/
podTemplate(yaml: '''
apiVersion: v1
kind: Pod
spec:
  containers:
  - name: docker
    image: docker:19.03.1
    command:
    - sleep
    args:
    - 99d
    env:
      - name: DOCKER_HOST
        value: tcp://localhost:2375
  - name: docker-daemon
    image: docker:19.03.1-dind
    securityContext:
      privileged: true
    env:
      - name: DOCKER_TLS_CERTDIR
        value: ""
''') {
    node(POD_LABEL) {
        git 'https://github.com/jenkinsci/docker-jnlp-slave.git'
        container('docker') {
            sh 'docker version && DOCKER_BUILDKIT=1 docker build --progress plain -t testing .'
        }
    }
}