A stable, well-tested, highly configurable way of checking your Dockerfile(s) with hadolint.

Verify your dockerfiles with hadolint for pull requests:

name: Lint
on: pull_request

jobs:
  hadolint:
    runs-on: ubuntu-slim
    name: Hadolint
    steps:
      - uses: actions/checkout@v6
      - uses: jbergstroem/hadolint-gh-action@v1

More usage examples can be found in USAGE.md.

The GitHub Action accepts a version input to switch to or pin a specific version of hadolint.

The output variable hadolint_version will always contain what version the action is running. This can be useful in debugging scenarios where things "break" from one day to the other due to the action being updated.

The shell scripts are developed against the latest version available (which is the default value for the input).

You can control the behavior of how hadolint presents its findings by configuring:

• annotate: let feedback show inline in your code review
• output_format: store the output in a variable you can pass on to other processing tools

If output_format is set, the GitHub Action variable hadolint_output will contain the output. You can choose what format you prefer depending on how you want to process the results.

These output variables are always populated:

• hadolint_version: the version of hadolint used while running the action
• hadolint_gh_action_version: the version of this action while running it

Enable advanced_security to upload hadolint findings to the GitHub Advanced Security dashboard. Results appear in the Security tab of your repository, providing centralized vulnerability tracking.

- uses: jbergstroem/hadolint-gh-action@v1
  with:
    advanced_security: true

Note: Requires security-events: write permission. See USAGE.md for a detailed example.

Also known as "can I run this in production". The action itself is tested via CI for all its use cases as well as unit tests for each function. Additionally, shellcheck is run against all shell scripts. Releases are cut manually (for now) and the action will strictly follow semver with regards to breaking functionality or options.

Due to staying with bash we can avoid Docker-related performance penalties. Yet to be benchmarked, but it is likely on par or faster than other hadolint actions.