Docker build-with-cache action

This action builds your docker image and cache the stages (supports multi-stage builds) to improve building times in subsequent builds.

By default it pushes the image with all the stages to a registry, but you can disable this feature setting push_image_and_stages to false.

Inputs

Required

username: Docker registry's user.

password: Docker registry's password.

image_name: Image name with namespace (eg: whoan/node).

Optional

registry: Docker registry (default: Docker Hub's registry).

image_tag: Tag of the image to build (default: latest).

context: Docker context (default: ./).

dockerfile: Dockerfile filename path (default: "$context"/Dockerfile)

push_image_and_stages: Set to false to avoid pushing to registry (default: true). You might want to set this option to false if you plan to use this action for PRs to avoid overriding cached stages in the registry.

build_extra_args: Provide extra arguments to docker build. eg: "--compress=true --build-arg=hello=world"

Outputs

None

How it works

The action does the following every time it is triggered:

• Pull previously pushed stages (if any) from the specified registry (default: https://hub.docker.com)
• Build the image using cache (ie: using the pulled stages)
• Push each stage of the built image to the registry with the name <image_name>-stages:<1,2,3,...>
• Push the image itself like <image_name>:<image_tag>
• Push any git tag if available like <image_name>:<git_tag>

Example usage

Minimal example:

- uses: whoan/docker-build-with-cache-action@v2
  with:
    username: whoan
    password: "${{ secrets.DOCKER_PASSWORD }}"
    image_name: whoan/node

You can see a full working example in this repo using GitHub's registry:

- uses: whoan/docker-build-with-cache-action@v2
  with:
    username: "${{ secrets.DOCKER_USERNAME }}"
    password: "${{ secrets.DOCKER_PASSWORD }}"
    image_name: whoan/docker-images/node
    image_tag: alpine-slim
    registry: docker.pkg.github.com
    context: node-alpine-slim
    build_extra_args: "--compress=true --build-arg=hello=world"

More info here on how to get username/password for GitHub's registry.

Another example for Google Cloud Platform and more custom settings:

- uses: whoan/docker-build-with-cache-action@v2
  with:
    username: _json_key
    password: "${{ secrets.DOCKER_PASSWORD }}"
    registry: gcr.io
    image_name: your_id/your_image
    image_tag: latest
    context: sub_folder_in_your_repo
    dockerfile: custom.dockerfile
    push_image_and_stages: false  # useful when you are setting a workflow to run on PRs

Cache is not working?

Be aware of the conditions that can invalidate your cache:

• Be specific with the base images. If you start from an image with latest tag, it may download different versions when the action is triggered, and it will invalidate the cache.

License

MIT