prek/.github/workflows/build-docker.yml

# Build and publish a Docker image.
#
# Assumed to run as a subworkflow of .github/workflows/release.yml; specifically, as a local
# artifacts job within `cargo-dist`.
#
# Adapted from https://github.com/astral-sh/ty/blob/main/.github/workflows/build-docker.yml
name: "Build Docker image"

on:
  workflow_call:
    inputs:
      plan:
        required: true
        type: string
  pull_request:
    paths:
      - .github/workflows/build-docker.yml

env:
  PREK_BASE_IMG: ghcr.io/${{ github.repository_owner }}/prek

permissions:
  contents: read
  # TODO(zanieb): Ideally, this would be `read` on dry-run but that will require
  # significant changes to the workflow.
  packages: write # zizmor: ignore[excessive-permissions]

jobs:
  docker-build:
    name: Build Docker image ghcr.io/j178/prek for ${{ matrix.platform }}
    runs-on: ubuntu-latest
    environment:
      name: release
    strategy:
      fail-fast: false
      matrix:
        platform:
          - linux/amd64
          - linux/arm64
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          persist-credentials: false

      - uses: docker/setup-buildx-action@8d2750c68a42422c14e847fe6c8ac0403b4cbd6f # v3.12.0

      - uses: docker/login-action@5e57cd118135c172c3672efd75eb46360885c0ef # v3.6.0
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Check tag consistency
        if: ${{ inputs.plan != '' && !fromJson(inputs.plan).announcement_tag_is_implicit }}
        env:
          TAG: ${{ inputs.plan != '' && fromJson(inputs.plan).announcement_tag || 'dry-run' }}
        run: |
          version=$(grep -m 1 "^version = " pyproject.toml | sed -e 's/version = "\(.*\)"/\1/g')
          if [ "${TAG}" != "v${version}" ]; then
            echo "The input tag does not match the version from pyproject.toml:" >&2
            echo "${TAG}" >&2
            echo "${version}" >&2
            exit 1
          else
            echo "Releasing ${version}"
          fi

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@c299e40c65443455700f0fdfc63efafe5b349051 # v5.10.0
        env:
          DOCKER_METADATA_ANNOTATIONS_LEVELS: index
        with:
          images: ${{ env.PREK_BASE_IMG }}
          # Defining this makes sure the org.opencontainers.image.version OCI label becomes the actual release version and not the branch name
          tags: |
            type=raw,value=dry-run,enable=${{ inputs.plan == '' || fromJson(inputs.plan).announcement_tag_is_implicit }}
            type=semver,pattern={{ raw }},value=${{ inputs.plan != '' && fromJson(inputs.plan).announcement_tag || 'dry-run' }},enable=${{ inputs.plan != '' && !fromJson(inputs.plan).announcement_tag_is_implicit }}

      - name: Normalize Platform Pair (replace / with -)
        run: |
          platform=${{ matrix.platform }}
          echo "PLATFORM_TUPLE=${platform//\//-}" >> "$GITHUB_ENV"

      # Adapted from https://docs.docker.com/build/ci/github-actions/multi-platform/
      - name: Build and push by digest
        id: build
        uses: docker/build-push-action@263435318d21b8e681c14492fe198d362a7d2c83 # v6.18.0
        with:
          context: .
          platforms: ${{ matrix.platform }}
          cache-from: type=gha,scope=prek-${{ env.PLATFORM_TUPLE }}
          cache-to: type=gha,mode=min,scope=prek-${{ env.PLATFORM_TUPLE }}
          labels: ${{ steps.meta.outputs.labels }}
          outputs: type=image,name=${{ env.PREK_BASE_IMG }},push-by-digest=true,name-canonical=true,push=${{ inputs.plan != '' && !fromJson(inputs.plan).announcement_tag_is_implicit }}

      - name: Export digests
        env:
          digest: ${{ steps.build.outputs.digest }}
        run: |
          mkdir -p /tmp/digests
          touch "/tmp/digests/${digest#sha256:}"

      - name: Upload digests
        uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6.0.0
        with:
          name: digests-${{ env.PLATFORM_TUPLE }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

  docker-publish:
    name: Publish Docker image (ghcr.io/j178/prek)
    runs-on: ubuntu-latest
    environment:
      name: release
    needs:
      - docker-build
    if: ${{ inputs.plan != '' && !fromJson(inputs.plan).announcement_tag_is_implicit }}
    steps:
      - name: Download digests
        uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7.0.0
        with:
          path: /tmp/digests
          pattern: digests-*
          merge-multiple: true

      - uses: docker/setup-buildx-action@8d2750c68a42422c14e847fe6c8ac0403b4cbd6f # v3.12.0

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@c299e40c65443455700f0fdfc63efafe5b349051 # v5.10.0
        env:
          DOCKER_METADATA_ANNOTATIONS_LEVELS: index
        with:
          images: ${{ env.PREK_BASE_IMG }}
          # Order is on purpose such that the label org.opencontainers.image.version has the first pattern with the full version
          tags: |
            type=raw,value=${{ fromJson(inputs.plan).announcement_tag }}
            type=semver,pattern=v{{ major }}.{{ minor }},value=${{ fromJson(inputs.plan).announcement_tag }}

      - uses: docker/login-action@5e57cd118135c172c3672efd75eb46360885c0ef # v3.6.0
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}

      # Adapted from https://docs.docker.com/build/ci/github-actions/multi-platform/
      - name: Create manifest list and push
        working-directory: /tmp/digests
        # The jq command expands the docker/metadata json "tags" array entry to `-t tag1 -t tag2 ...` for each tag in the array
        # The printf will expand the base image with the `<PREK_BASE_IMG>@sha256:<sha256> ...` for each sha256 in the directory
        # The final command becomes `docker buildx imagetools create -t tag1 -t tag2 ... <PREK_BASE_IMG>@sha256:<sha256_1> <PREK_BASE_IMG>@sha256:<sha256_2> ...`
        run: |
          # shellcheck disable=SC2046
          readarray -t lines <<< "$DOCKER_METADATA_OUTPUT_ANNOTATIONS"; annotations=(); for line in "${lines[@]}"; do annotations+=(--annotation "$line"); done

          docker buildx imagetools create \
            "${annotations[@]}" \
            $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            $(printf "${PREK_BASE_IMG}@sha256:%s " *)