Build and Push Multi Architecture Containers in Github Actions

This is an example repository to demonstrate Multi-Platform/Multi-arch container builds in GitHub actions to ghcr.io registry.

Create a workflow

Create .github/workflows/main.yml file.

Fill and change yml file with your properties.
In this example, github actions is triggered on master branch publish and builds container image with linux/amd64,linux/arm/v7,linux/arm64 platforms.

name: Build and publish container

on:
  push:
    branches: [master]
  workflow_dispatch:
    inputs:
      reason:
        description: 'Why ?'
        required: false
        default: ''

jobs:
  ghr_push:
    runs-on: ubuntu-latest
    if: github.event_name == 'push'

    steps:
      - name: checkout
        uses: actions/checkout@v2

      - name: Set up QEMU
        uses: docker/setup-qemu-action@v1

      - name: Set up Docker Buildx
        id: buildx
        uses: docker/setup-buildx-action@v1

      - name: Log-in to ghcr.io
        run: echo "${{ secrets.GITHUB_TOKEN }}" | docker login https://ghcr.io -u ${{ github.actor }} --password-stdin

      - name: Build and push container image
        run: |
          IMAGE_ID=$(echo ghcr.io/${{ github.repository }} | tr '[A-Z]' '[a-z]')
          # Strip git ref prefix from version
          VERSION=$(echo "${{ github.ref }}" | sed -e 's,.*/\(.*\),\1,')
          # Strip "v" prefix from tag name
          [[ "${{ github.ref }}" == "refs/tags/"* ]] && VERSION=$(echo $VERSION | sed -e 's/^v//')
          # when the branch is master, replace master with latest
          [ "$VERSION" == "master" ] && VERSION=latest
          echo IMAGE_ID=$IMAGE_ID
          echo VERSION=$VERSION
          # Build and Publish container image
          docker buildx build --push \
          --tag $IMAGE_ID:$VERSION \
          --platform linux/amd64,linux/arm/v7,linux/arm64 .

Link repository

Label

First method to linking repository with the containers is LABEL option in Dockerfile.

Create a LABEL instruction in Dockerfile to link package to source.

LABEL org.opencontainers.image.source="https://github.com/{Your username}/{your repository name}"

# Example

LABEL org.opencontainers.image.source="https://github.com/ahmetozer/github-actions-multi-arch-container-ghcr.io"

NOTE: If your Dockerfile has a multi stage, add LABEL after latest FROM option.

Github Web

You can also connect repository to container package from github web.

Open https://github.com/users/{username}/packages/container/package/{repo-name} on your browser.

End of the page, you will see repository connect setting, clink to 'Connect Repository' button and select your repository.

Change package visibility

By default, packages are private. To allow public access, change visibility of the package from private to public on https://github.com/users/{username}/packages/container/{repo-name}/settings page.