circle.yml

# These environment variables must be set in CircleCI UI
#
# DOCKERHUB_REPO - docker hub repo, format: <username>/<repo>
# DOCKER_EMAIL   - login info for docker hub
# DOCKER_USER
# DOCKER_PASS
#
machine:
  services:
    - docker

dependencies:
  # make sure to keep the docker cache dir
  cache_directories:
    - "~/docker"

  override:
    - docker info
    - docker login -e $DOCKER_EMAIL -u $DOCKER_USER -p $DOCKER_PASS
    - "[ ! -z $DOCKERHUB_REPO ]"

    # build the container, use circleci's docker cache workaround
    # only use 1 image per day to keep the cache size from getting 
    # too big and slowing down the build
    - I="image-$(date +%j).tar"; if [[ -e ~/docker/$I ]]; then echo "Loading $I"; docker load -i ~/docker/$I; fi

    - docker build -t app:build .

    # Clean up any old images and save the new one
    - I="image-$(date +%j).tar"; mkdir -p ~/docker; rm ~/docker/*; docker save app:build > ~/docker/$I; ls -l ~/docker

test:
  override:
    - docker run app:build test

# appropriately tag and push the container to dockerhub
deployment:
  hub_latest:
    branch: "master"
    commands:
      - "docker tag app:build ${DOCKERHUB_REPO}:latest"
      - "docker push ${DOCKERHUB_REPO}:latest"

  hub_releases:
    # push all tags
    tag: /.*/
    commands:
      - "echo ${DOCKERHUB_REPO}:${CIRCLE_TAG}"
      - "docker tag app:build ${DOCKERHUB_REPO}:${CIRCLE_TAG}"
      - "docker images"
      - "docker push ${DOCKERHUB_REPO}:${CIRCLE_TAG}"