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:
  override:
    - docker info

    # create a version.json
    - >
        printf '{"commit":"%s","version":"%s","source":"https://github.com/%s/%s","build":"%s"}\n' 
        "$CIRCLE_SHA1" 
        "$CIRCLE_TAG"
        "$CIRCLE_PROJECT_USERNAME"
        "$CIRCLE_PROJECT_REPONAME"
        "$CIRCLE_BUILD_URL"
        > version.json

    - docker build -t app:build .

    # write the sha256 sum to an artifact to make image verification easier
    - docker images --no-trunc | awk '/^app/ {print $3}' | tee $CIRCLE_ARTIFACTS/docker-image-shasum256.txt

test:
  override:
    - docker run app:build test

# appropriately tag and push the container to dockerhub
deployment:
  hub_latest:
    branch: "master"
    commands:
      - "[ ! -z $DOCKERHUB_REPO ]"
      - docker login -e $DOCKER_EMAIL -u $DOCKER_USER -p $DOCKER_PASS
      - "docker tag app:build ${DOCKERHUB_REPO}:latest"
      - "docker push ${DOCKERHUB_REPO}:latest"

  hub_releases:
    # push all tags
    tag: /.*/
    commands:
      - "[ ! -z $DOCKERHUB_REPO ]"
      - docker login -e $DOCKER_EMAIL -u $DOCKER_USER -p $DOCKER_PASS
      - "echo ${DOCKERHUB_REPO}:${CIRCLE_TAG}"
      - "docker tag app:build ${DOCKERHUB_REPO}:${CIRCLE_TAG}"
      - "docker images"
      - "docker push ${DOCKERHUB_REPO}:${CIRCLE_TAG}"