release.yml

name: release
on:
  # Test that this workflow works on every pull_request or merge group;
  # goreleaser is put into snapshot mode when not on a tag
  pull_request:
  merge_group:
  # Run when a tag is pushed.
  push:
    tags:
      - v*

env:
  REGISTRY: ghcr.io

jobs:
  goreleaser:
    runs-on: ubuntu-latest
    permissions:
      # goreleaser uploads artifacts to the releases api
      contents: write
      # goreleaser uploads images to container registry
      packages: write
    env:
      flags: ""
    outputs:
      binary_hashes: ${{ steps.binary.outputs.hashes }}
      image_subjects: ${{ steps.image.outputs.subjects }}
    steps:
      - if: ${{ !startsWith(github.ref, 'refs/tags/') }}
        run: echo "flags=--snapshot" >> $GITHUB_ENV
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      - run: git fetch --force --tags
      - uses: actions/setup-go@v5
        with:
          go-version-file: 'go.mod'
          cache: true
      - uses: docker/login-action@v3.3.0
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}
      - uses: goreleaser/goreleaser-action@v6
        id: goreleaser
        with:
          version: latest
          args: release --clean ${{ env.flags }}
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      - name: generate hashes for binary artifacts
        id: binary
        env:
          ARTIFACTS: "${{ steps.goreleaser.outputs.artifacts }}"
        run: |
          set -exuo pipefail
          checksum_file=$(echo "${ARTIFACTS}" | jq -r '.[] | select (.type=="Checksum") | .path')
          echo "hashes=$(cat ${checksum_file} | base64 -w0)" >> "${GITHUB_OUTPUT}"
      - name: generate digest for container image
        id: image
        env:
          ARTIFACTS: "${{ steps.goreleaser.outputs.artifacts }}"
        run: |
          set -exuo pipefail
          image_list=$(echo -e "${ARTIFACTS}" | jq -r '.[] | select(.type=="Docker Manifest") | {"image": (.name | sub("^.*?/"; "") | sub(":(.*)"; "")), "digest": .extra.Digest}')
          echo "subjects=$(echo $image_list | jq -c -s 'unique_by(.digest) | {"include": .}')" >> "$GITHUB_OUTPUT"

  binary-provenance:
    needs: [goreleaser]
    if: ${{ startsWith(github.ref, 'refs/tags/') }}
    permissions:
      actions: read # To read the workflow path.
      id-token: write # To sign the provenance.
      contents: write # To add assets to a release.
    uses: slsa-framework/slsa-github-generator/.github/workflows/generator_generic_slsa3.yml@v2.0.0
    with:
      base64-subjects: "${{ needs.goreleaser.outputs.binary_hashes }}"
      upload-assets: true # upload to a new release

  binary-verify:
    needs: [goreleaser, binary-provenance]
    if: ${{ startsWith(github.ref, 'refs/tags/') }}
    runs-on: ubuntu-latest
    permissions:
      contents: read
    steps:
      - uses: slsa-framework/slsa-verifier/actions/installer@v2.6.0
      - name: download assets
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -exuo pipefail
          gh release download "${GITHUB_REF_NAME}" --repo "${GITHUB_REPOSITORY}"
      - name: verify assets
        env:
          CHECKSUMS: ${{ needs.goreleaser.outputs.binary_hashes }}
          PROVENANCE: "${{ needs.binary-provenance.outputs.provenance-name }}"
        run: |
          set -exuo pipefail
          echo "$CHECKSUMS" | base64 -d | while read -r line; do
              fn=$(echo $line | cut -d ' ' -f2)
              echo "Verifying $fn"
              slsa-verifier verify-artifact --provenance-path "$PROVENANCE" \
                                            --source-uri "github.com/$GITHUB_REPOSITORY" \
                                            --source-tag "$GITHUB_REF_NAME" \
                                            "$fn"
          done

  image-provenance:
    needs: [goreleaser]
    if: ${{ startsWith(github.ref, 'refs/tags/') }}
    permissions:
      actions: read
      id-token: write
      packages: write
    strategy:
      matrix: ${{ fromJSON(needs.goreleaser.outputs.image_subjects) }}
    uses: slsa-framework/slsa-github-generator/.github/workflows/generator_container_slsa3.yml@v2.0.0
    with:
      image: ghcr.io/${{ matrix.image }}
      digest: ${{ matrix.digest }}
      registry-username: ${{ github.actor }}
    secrets:
      registry-password: ${{ secrets.GITHUB_TOKEN }}

  image-verify:
    needs: [goreleaser, image-provenance]
    if: ${{ startsWith(github.ref, 'refs/tags/') }}
    runs-on: ubuntu-latest
    permissions:
      contents: read
    strategy:
      matrix: ${{ fromJSON(needs.goreleaser.outputs.image_subjects) }}
    steps:
      - uses: docker/login-action@v3.3.0
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}
      - uses: sigstore/cosign-installer@v3.7.0
      - name: verify image
        env:
          IMAGE: ${{ matrix.image }}
          DIGEST: ${{ matrix.digest }}
        run: |
          cosign verify-attestation \
             --type slsaprovenance \
             --certificate-oidc-issuer https://token.actions.githubusercontent.com \
             --certificate-identity-regexp '^https://github.com/slsa-framework/slsa-github-generator/.github/workflows/generator_container_slsa3.yml@refs/tags/v[0-9]+.[0-9]+.[0-9]+$' \
             ${REGISTRY}/${IMAGE}@${DIGEST}