image: docker:latest

variables:
  DOCKER_HOST: tcp://localhost:2375/
  DOCKER_DRIVER: overlay2
  CoNTAINER_TEST_IMAGE: "$CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG"
  CONTAINER_RELEASE_IMAGE: "$CI_REGISTRY_IMAGE:latest"

services:
  - docker:dind

stages:
  - build
  - release

before_script:
  - docker info
  - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" "$CI_REGISTRY"

build:
  stage: build
  script:
    - docker build --pull -t "$CONTAINER_TEST_IMAGE" .
    - docker push "$CONTAINER_TEST_IMAGE"

release-image:
  stage: release
  script:
    - docker pull "$CONTAINER_TEST_IMAGE"
    - docker tag "$CONTAINER_TEST_IMAGE" "$CONTAINER_RELEASE_IMAGE"
    - docker push "$CONTAINER_RELEASE_IMAGE"
  only:
    - master