preview-deploy.yml

name: Preview Deploy

on:
  pull_request:
    types: [opened, synchronize, reopened, closed]

concurrency:
  group: preview-${{ github.event.pull_request.number }}
  cancel-in-progress: true

env:
  FLY_APP: docs-preview-pr-${{ github.event.pull_request.number }}
  FLY_ORG: ${{ vars.FLY_ORG || 'personal' }}

jobs:
  build-and-deploy:
    if: github.event.action != 'closed'
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write

    steps:
      - name: Checkout
        uses: actions/checkout@v6
        with:
          # Full history (and all branches) is needed to diff against the merge
          # base with the PR's base branch, which isn't always main
          fetch-depth: 0

      - name: Generate change manifest
        env:
          PREVIEW_URL: https://${{ env.FLY_APP }}.fly.dev
          # Diff against the branch the PR targets, so a stacked PR lists only
          # its own changes instead of the whole stack
          PREVIEW_BASE_REF: origin/${{ github.event.pull_request.base.ref }}
          # The PR head commit (GITHUB_SHA is the synthetic merge ref on PRs)
          GITHUB_SHA: ${{ github.event.pull_request.head.sha }}
        run: node scripts/generate-preview-changes.mjs

      - name: Set up Fly CLI
        uses: superfly/flyctl-actions/setup-flyctl@fc53c09e1bc3be6f54706524e3b82c4f462f77be # v1.5

      - name: Create Fly app (if not exists)
        run: |
          flyctl apps create "${{ env.FLY_APP }}" --org "${{ env.FLY_ORG }}" 2>/dev/null || true
        env:
          FLY_API_TOKEN: ${{ secrets.FLY_API_TOKEN }}

      - name: Generate fly.toml
        run: |
          cat > fly.toml <<EOF
          app = "${{ env.FLY_APP }}"
          primary_region = "ams"

          [build]
            dockerfile = "Dockerfile.preview"

          [http_service]
            internal_port = 8210
            force_https = true
            auto_stop_machines = "stop"
            min_machines_running = 0

          [[vm]]
            size = "shared-cpu-1x"
            memory = "256mb"
          EOF

      - name: Deploy to Fly.io
        run: |
          flyctl deploy \
            --ha=false \
            --remote-only \
            --build-arg VAADIN_PRO_KEY="${{ secrets.VAADIN_PRO_KEY }}"
        env:
          FLY_API_TOKEN: ${{ secrets.FLY_API_TOKEN }}

      - name: Comment preview URL on PR
        uses: marocchino/sticky-pull-request-comment@v2
        with:
          header: preview-deploy
          path: preview-comment.md

  cleanup:
    if: github.event.action == 'closed'
    runs-on: ubuntu-latest
    steps:
      - name: Set up Fly CLI
        uses: superfly/flyctl-actions/setup-flyctl@fc53c09e1bc3be6f54706524e3b82c4f462f77be # v1.5

      - name: Destroy Fly app
        run: |
          if flyctl apps list --json | jq -e --arg name "${{ env.FLY_APP }}" '.[] | select(.Name == $name)' > /dev/null; then
            flyctl apps destroy "${{ env.FLY_APP }}" --yes
          else
            echo "App ${{ env.FLY_APP }} does not exist, nothing to destroy"
          fi
        env:
          FLY_API_TOKEN: ${{ secrets.FLY_API_TOKEN }}