.gitlab-ci.yml

before_script:
  - docker version
  - docker login -u "$REPO_USER" -p "$REPO_PASSWORD" $CI_REGISTRY

variables:
  DOCKER_BUILDKIT: 0
  CI_REGISTRY_IMAGE: "nexus.slh.lan:8123/voip/call-recorder"

Build:
  stage: build
  script:
    - export 
    # fetches the latest image (not failing if image is not found)
    - docker pull $CI_REGISTRY_IMAGE:latest || true
    # builds the project, passing proxy variables, and vcs vars for LABEL
    # notice the cache-from, which is going to use the image we just pulled locally
    # the built image is tagged locally with the commit SHA, and then pushed to 
    # the GitLab registry
    - >
      docker build
      --build-arg ENV_VERSION=${CI_COMMIT_SHA:0:8}
      --pull
      --cache-from $CI_REGISTRY_IMAGE:latest
      --tag $CI_REGISTRY_IMAGE:${CI_COMMIT_SHA:0:8}
      .
    - docker push $CI_REGISTRY_IMAGE:${CI_COMMIT_SHA:0:8}

    # Here, the goal is to tag the "master" branch as "latest"
Push latest:
  variables:
    # We are just playing with Docker here. 
    # We do not need GitLab to clone the source code.
    GIT_STRATEGY: none
  stage: deploy
  only:
    # Only "master" should be tagged "latest"
    - master
  script:
    # Because we have no guarantee that this job will be picked up by the same runner 
    # that built the image in the previous step, we pull it again locally
    - docker pull $CI_REGISTRY_IMAGE:${CI_COMMIT_SHA:0:8}
    # Then we tag it "latest"
    - docker tag $CI_REGISTRY_IMAGE:${CI_COMMIT_SHA:0:8} $CI_REGISTRY_IMAGE:latest
    # Annnd we push it.
    - docker push $CI_REGISTRY_IMAGE:latest

Push tag:
  variables:
    # Again, we do not need the source code here. Just playing with Docker.
    GIT_STRATEGY: none
  stage: deploy
  only:
    # We want this job to be run on tags only.
    - tags
  script:
    - docker pull $CI_REGISTRY_IMAGE:${CI_COMMIT_SHA:0:8}
    - docker tag $CI_REGISTRY_IMAGE:${CI_COMMIT_SHA:0:8} $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_NAME
    - docker push $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_NAME