.gitlab-ci.yml

image: docker:stable

services:
  - docker:dind

variables:
  DOCKER_HOST: tcp://docker:2375
  DOCKER_DRIVER: overlay2

before_script:
  - docker login -u $CI_REGISTRY_USER -p $CI_JOB_TOKEN $CI_REGISTRY

build-master:
  stage: build
  script:
    - docker pull "$CI_REGISTRY_IMAGE" || true
    - docker pull "$CI_REGISTRY_IMAGE:builder" || true
    - docker build --pull --cache-from "$CI_REGISTRY_IMAGE" --cache-from "$CI_REGISTRY_IMAGE:builder" -t "$CI_REGISTRY_IMAGE" .
    - docker build --pull --cache-from "$CI_REGISTRY_IMAGE:builder" --target builder -t "$CI_REGISTRY_IMAGE:builder" .
    - docker push "$CI_REGISTRY_IMAGE"
    - docker push "$CI_REGISTRY_IMAGE:builder"
  only:
    - master

build-tags:
  stage: build
  script:
    - docker pull "$CI_REGISTRY_IMAGE" || true
    - docker pull "$CI_REGISTRY_IMAGE:builder" || true
    - docker build --pull --cache-from "$CI_REGISTRY_IMAGE" --cache-from "$CI_REGISTRY_IMAGE:builder" -t "$CI_REGISTRY_IMAGE:$CI_COMMIT_TAG" .
    - docker push "$CI_REGISTRY_IMAGE:$CI_COMMIT_TAG"
  only:
    - tags

build-ref:
  stage: build
  script:
    - docker pull $CI_REGISTRY_IMAGE:latest || true
    - docker pull "$CI_REGISTRY_IMAGE:builder" || true
    - docker build --pull --cache-from "$CI_REGISTRY_IMAGE" --cache-from "$CI_REGISTRY_IMAGE:builder" -t "$CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG" .
    - docker push "$CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG"
  only:
    - branches
  except:
    - master