build-and-sign-image.yml

# This workflow will build and push a signed Docker image

name: Build and sign image

on:
  push:
    tags:
      - "v[0-9]+.[0-9]+.[0-9]+"
env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}

jobs:
  build_and_sign_image:
    runs-on: ubuntu-latest
    permissions:
      contents: write
      packages: write
      id-token: write
      security-events: write

    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Clear Sigstore cache
        run: rm -rf ~/.sigstore

      - uses: anchore/sbom-action@v0
        with:
          image: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          output-file: ./nginx-loadbalancer-kubernetes-${{env.GITHUB_REF_NAME}}.spdx.json
          registry-username: ${{ github.actor }}
          registry-password: ${{ secrets.GITHUB_TOKEN }}

      - name: Install cosign
        uses: sigstore/cosign-installer@dc72c7d5c4d10cd6bcb8cf6e3fd625a9e5e537da #v3.7.0
        with:
          cosign-release: 'v2.4.1'

      - name: Log into registry ${{ env.REGISTRY }} for ${{ github.actor }}
        uses: docker/login-action@343f7c4344506bcbf9b4de18042ae17996df046d
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@9dc751fe249ad99385a2583ee0d084c400eee04e
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}

      - name: Build Docker Image
        id: docker-build-and-push
        uses: docker/build-push-action@4a13e500e55cf31b7a5d59a38ab2040ab0f42f56
        with:
          context: .
          file: ./Dockerfile
          push: true
          tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest,${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{github.run_number}}

      - name: Sign the published Docker images
        env:
          COSIGN_EXPERIMENTAL: "true"
        # This step uses the identity token to provision an ephemeral certificate
        # against the sigstore community Fulcio instance.
        run: cosign sign --yes "${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}@${{ steps.docker-build-and-push.outputs.digest }}"

      # NOTE: This runs statically against the latest tag in Docker Hub which was not produced by this workflow
      # This should be updated once this workflow is fully implemented
      - name: Run Trivy vulnerability scanner
        uses: aquasecurity/trivy-action@91713af97dc80187565512baba96e4364e983601 # 0.16.0
        continue-on-error: true
        with:
          image-ref: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
          format: 'sarif'
          output: 'trivy-results-${{ inputs.image }}.sarif'
          ignore-unfixed: 'true'

      - name: Upload Trivy scan results to GitHub Security tab
        uses: github/codeql-action/upload-sarif@012739e5082ff0c22ca6d6ab32e07c36df03c4a4 # v2.2.11
        continue-on-error: true
        with:
          sarif_file: 'trivy-results-${{ inputs.image }}.sarif'
          sha: ${{ github.sha }}
          ref: ${{ github.ref }}

      - name: Generate Release
        uses: ncipollo/release-action@v1
        with:
          artifacts: |
            trivy-results-${{ inputs.image }}.sarif
            ./nginx-loadbalancer-kubernetes-${{env.GITHUB_REF_NAME}}.spdx.json
          body: |
            # Release ${{env.GITHUB_REF_NAME}}
            ## Changelog
            ${{ steps.meta.outputs.changelog }}
          generateReleaseNotes: true
          makeLatest: false
          name: "${{env.GITHUB_REF_NAME}}"