release.yml

name: release

on:
  push:
    tags:
      - 'v*'

permissions:
  contents: write
  packages: write

env:
  IMAGE: ghcr.io/${{ github.repository_owner }}/bytebucket

jobs:
  # Build each platform on its own native runner, publish by digest, then merge.
  # Native beats QEMU emulation by ~5x on a cold cache; arm64 on QEMU was
  # taking 20+ minutes for a single multi-arch job.
  build:
    strategy:
      fail-fast: false
      matrix:
        include:
          - platform: linux/amd64
            runner: ubuntu-latest
          - platform: linux/arm64
            runner: ubuntu-24.04-arm
    runs-on: ${{ matrix.runner }}
    steps:
      - name: Compute platform pair
        id: plat
        run: echo "pair=${{ matrix.platform }}" | tr '/' '-' >> "$GITHUB_OUTPUT"

      - name: Checkout
        uses: actions/checkout@v6

      - name: Set up Buildx
        uses: docker/setup-buildx-action@v4

      - name: Log in to GHCR
        uses: docker/login-action@v4
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Metadata (labels only)
        id: meta
        uses: docker/metadata-action@v6
        with:
          images: ${{ env.IMAGE }}

      - name: Build and push by digest
        id: build
        uses: docker/build-push-action@v7
        with:
          context: .
          file: docker/Dockerfile
          platforms: ${{ matrix.platform }}
          labels: ${{ steps.meta.outputs.labels }}
          outputs: type=image,name=${{ env.IMAGE }},push-by-digest=true,name-canonical=true,push=true
          cache-from: type=gha,scope=${{ matrix.platform }}
          cache-to: type=gha,mode=max,scope=${{ matrix.platform }}

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

      - name: Upload digest
        uses: actions/upload-artifact@v7
        with:
          name: digest-${{ steps.plat.outputs.pair }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

  manifest:
    needs: build
    runs-on: ubuntu-latest
    steps:
      - name: Download digests
        uses: actions/download-artifact@v8
        with:
          path: /tmp/digests
          pattern: digest-*
          merge-multiple: true

      - name: Set up Buildx
        uses: docker/setup-buildx-action@v4

      - name: Log in to GHCR
        uses: docker/login-action@v4
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Compute image tags
        id: meta
        uses: docker/metadata-action@v6
        with:
          images: ${{ env.IMAGE }}
          tags: |
            type=semver,pattern={{version}}
            type=semver,pattern={{major}}.{{minor}}
            type=semver,pattern={{major}}
            type=raw,value=latest,enable=${{ !contains(github.ref_name, '-') }}

      - name: Create manifest list
        working-directory: /tmp/digests
        run: |
          set -euo pipefail
          # Turn the tags output (newline list) into -t flags, then append the
          # per-platform image digests so the resulting manifest list resolves
          # the right platform at pull time.
          tag_args=$(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON")
          digests=""
          for f in *; do
            digests+=" ${IMAGE}@sha256:${f}"
          done
          eval docker buildx imagetools create ${tag_args} ${digests}

      - name: Inspect manifest
        run: |
          set -euo pipefail
          first_tag=$(jq -cr '.tags[0]' <<< "$DOCKER_METADATA_OUTPUT_JSON")
          docker buildx imagetools inspect "$first_tag"

  release:
    needs: manifest
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v6
        with:
          fetch-depth: 0

      - name: Create GitHub Release
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -euo pipefail
          tag="${GITHUB_REF_NAME}"
          if [[ "$tag" == *-* ]]; then
            gh release create "$tag" --generate-notes --prerelease
          else
            gh release create "$tag" --generate-notes
          fi