.gitlab-ci.yml

image: docker:latest
stages:
  - build 
  - deploy
services:
  - docker:dind
before_script:
  - echo -n $CI_REGISTRY_PASSWORD | docker login -u $CI_REGISTRY_USER --password-stdin $CI_REGISTRY
Build:
  stage: build
  script:
    - docker pull $CI_REGISTRY_IMAGE:latest || true
    - >
      docker build
      --pull
      --cache-from $CI_REGISTRY_IMAGE:latest
      --label "org.opencontainers.image.title=$CI_PROJECT_TITLE"
      --label "org.opencontainers.image.url=$CI_PROJECT_URL"
      --label "org.opencontainers.image.created=$CI_JOB_STARTED_AT"
      --label "org.opencontainers.image.revision=$CI_COMMIT_SHA"
      --label "org.opencontainers.image.version=$CI_COMMIT_REF_NAME"
      --tag $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA
      .
    - docker push $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA
Deploy:
  variables:
    GIT_STRATEGY: none
  stage: deploy
  only:
    - master
  script:
    - docker pull $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA
    - docker tag $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA $CI_REGISTRY_IMAGE:latest
    - docker push $CI_REGISTRY_IMAGE:latest