docker-compose.yml

version: "2.4"
services:
  base:
    build:
      args:
        REPO_MOUNT_POINT: $REPO_MOUNT_POINT
        REPO_MOUNT_POINT_PARENT: $REPO_MOUNT_POINT_PARENT
        MAIN_YARN_DIR: $MAIN_YARN_DIR
        COMMIT_YARN_CLI: $COMMIT_YARN_CLI
        COMMIT_YARN_WORKSPACE_TOOLS_PLUGIN: $COMMIT_YARN_WORKSPACE_TOOLS_PLUGIN
      context: .

    # Image name is set explicitly because it's shared by other services:
    image: $BASE_IMAGE_NAME

    # Because `base` is strictly a utility service that is not part of the
    # app's run time, its `scale` is set to zero so that it doesn't run when
    # `docker-compose up` is invoked.
    scale: 0

  back-end:
    command: ["yarn", "workspace", "back-end", "start"]
    environment:
      PORT: $PORT
    image: $BASE_IMAGE_NAME

    # Ensure proper handling of signals:
    init: true

    ports:
      - $BACK_END_HOST_PORT:$PORT

    volumes:
      # Mount the codebase into the container:
      - .:$REPO_MOUNT_POINT:delegated

      # Mount Yarn's directory into the container. The `delegated`
      # configuration is very important because the Yarn directory will have to
      # handle a large number of file system reads/writes. See
      # https://docs.docker.com/docker-for-mac/osxfs-caching/#delegated
      - main_yarn_dir:$MAIN_YARN_DIR:delegated


  front-end:
    command: ["yarn", "workspace", "front-end", "start"]
    depends_on:
      # The `front-end` depends on the `back-end` because of shared volumes:
      - back-end
    environment:
      PORT: $PORT
      API_URL: http://$BACK_END_HOST_NAME:$BACK_END_HOST_PORT/
    image: $BASE_IMAGE_NAME
    init: true
    ports:
      - $FRONT_END_HOST_PORT:$PORT

    volumes_from:
      # Note that both the `front-end` and `back-end` services share the same
      # volume mounts. Because the `front-end` service re-uses the volumes of
      # the `back-end` service, if you want to run the `front-end` service in
      # isolation (`docker-compose run front-end`), you'll need to have either
      # run `docker-compose up` or `docker-compose run back-end` beforehand in
      # order to iniatilize the shared volume.
      - back-end

volumes:

  # Anonymous volume containing Yarn configurations and Yarn-produced
  # files/directories:
  main_yarn_dir: