rules:
  - id: avoid-apk-upgrade
    languages:
      - dockerfile
    message: >-
      Packages in base images should be up-to-date, removing the need for
      'apk upgrade'. If packages are out-of-date, consider contacting the
      base image maintainer.
    severity: INFO
    metadata:
      source-rule-url: https://github.com/hadolint/hadolint/wiki/DL3017
      references:
        - https://github.com/hadolint/hadolint/wiki/DL3017
      category: best-practice
      technology:
        - dockerfile
    pattern: RUN ... apk upgrade ...