docker-publish.yml (GitHub example)

https://github.com/actions/starter-workflows/blob/main/ci/docker-publish.yml

• Cosign, Buildx

name: Docker

# This workflow uses actions that are not certified by GitHub.
# They are provided by a third-party and are governed by
# separate terms of service, privacy policy, and support
# documentation.

on:
  schedule:
    - cron: $cron-daily
  push:
    branches: [ $default-branch ]
    # Publish semver tags as releases.
    tags: [ 'v*.*.*' ]
  pull_request:
    branches: [ $default-branch ]
 
env:
  # Use docker.io for Docker Hub if empty
  REGISTRY: ghcr.io
  # github.repository as <account>/<repo>
  IMAGE_NAME: $Template:Github.repository 


jobs:
  build:

    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
      # This is used to complete the identity challenge
      # with sigstore/fulcio when running outside of PRs.
      id-token: write

   steps:
     - name: Checkout repository
       uses: actions/checkout@v3

     # Install the cosign tool except on PR
     # https://github.com/sigstore/cosign-installer
     - name: Install cosign
       if: github.event_name != 'pull_request'
       uses: sigstore/cosign-installer@f3c664df7af409cb4873aa5068053ba9d61a57b6 #v2.6.0
       with:
         cosign-release: 'v1.13.1'
 

     # Workaround: https://github.com/docker/build-push-action/issues/461
     - name: Setup Docker buildx
       uses: docker/setup-buildx-action@79abd3f86f79a9d68a23c75a09a9a85889262adf

     # Login against a Docker registry except on PR
     # https://github.com/docker/login-action
     - name: Log into registry $Template:Env.REGISTRY
       if: github.event_name != 'pull_request'
       uses: docker/login-action@28218f9b04b4f3f62068d7b6ce6ca5b26e35336c
       with:
         registry: $Template:Env.REGISTRY
         username: $Template:Github.actor
         password: $Template:Secrets.GITHUB TOKEN

      # Extract metadata (tags, labels) for Docker
      # https://github.com/docker/metadata-action
      - name: Extract Docker metadata
        id: meta
        uses: docker/metadata-action@98669ae865ea3cffbcbaa878cf57c20bbf1c6c38
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}

      # Build and push Docker image with Buildx (don't push on PR)
      # https://github.com/docker/build-push-action
      - name: Build and push Docker image
        id: build-and-push
        uses: docker/build-push-action@ac9327eae2b366085ac7f6a2d02df8aa8ead720a
        with:
          context: .
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          cache-from: type=gha
          cache-to: type=gha,mode=max


      # Sign the resulting Docker image digest except on PRs.
      # This will only write to the public Rekor transparency log when the Docker
      # repository is public to avoid leaking data.  If you would like to publish
      # transparency data even for private images, pass --force to cosign below.
      # https://github.com/sigstore/cosign
      - name: Sign the published Docker image
        if: ${{ github.event_name != 'pull_request' }}
        env:
          COSIGN_EXPERIMENTAL: "true"
        # This step uses the identity token to provision an ephemeral certificate
        # against the sigstore community Fulcio instance.
        run: echo "${{ steps.meta.outputs.tags }}" | xargs -I {} cosign sign {}@${{ steps.build-and-push.outputs.digest }}

Related

• my-docker-publish.yml

See also

• GitHub Actions, act, .github/workflows/, ~/actions-runner/, svc.sh, deploy:, run:, runs-on:, uses:, steps:, jobs:, on:, env:, uses:, script:, continue-on-error:, template:, aws-actions, inputs:, GITHUB_ENV, needs:, github., GitHub runner, my-docker-publish.yml, GitHub Actions variables, GitHub Actions contexts, GitHub Actions Importer, If:, SLSA, Actions Runner Controller (ARC), $GITHUB OUTPUT, notify:, Marketplace, GITHUB_TOKEN