Build Docker image and push it to GPR

build.yml

on:
  push:
    branches:
      - master

jobs:
  build:
    name: Build
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v2
    - uses: machine-learning-apps/gpr-docker-publish@5b71bce8513330a62b8b61ba846d37caaf2a85ba
      with:
          image_name: 'my-image-name'
          dockerfile_path: 'Dockerfile'
          build_context: '.'
          cache: true
      env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

This is the most concise way to do...

• docker login docker.pkg.github.com ... with your GITHUB_TOKEN
• docker build ... from the dockerfile_path file with the build_context directory as context
• Create an image named according to image_name
• docker push to GPR

This will push into GPR within the repo that the action runs for.

So, for example, if this workflow lives in github.com/myorg/myrepo, the image will show up in github.com/myorg/myrepo/packages, and can be pulled with docker pull docker.pkg.github.com/myorg/myrepo/my-image-name.

Also, the image will be tagged with the SHA1 of the git commit that the action was run for.

cache pulls the latest version of the package and uses it as a build cache.

Note: In order to use the image from an other action, even if the repository hosting the image is public, you will need to docker login.

docker login docker.pkg.github.com --username username-ignored --password-stdin <<< '${{ secrets.GITHUB_TOKEN }}' should be sufficient.