Gitlab CI recommendations

stages:

    - build

    - release

before_script:

    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY

variables:

    DOCKER_HOST: tcp://docker:2375

    DOCKER_TLS_CERTDIR: ""

build:

    stage: build

    image: docker

    services:

        - docker:dind

    variables:

        DOCKER_HOST: tcp://docker:2375

        DOCKER_TLS_CERTDIR: ""

    script:

        - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY

        - docker build -t $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG -t $CI_REGISTRY_IMAGE:latest -f Dockerfile $CI_PROJECT_DIR

        - docker build --pull -t $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG -f Dockerfile $CI_PROJECT_DIR

        - docker push $CI_REGISTRY_IMAGE

release:

    stage: release

    script:

        - docker pull $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG

        - docker tag $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG $CI_REGISTRY_IMAGE:latest

        - docker push $CI_REGISTRY_IMAGE:latest

    only:

        master