nightly-benchmarks.yml

---
name: Nightly Benchmarks

on:
  schedule:
    # Run at 2 AM UTC every day
    - cron: "0 2 * * *"
  workflow_dispatch:
    inputs:
      jmh_args:
        description: "Additional JMH arguments (e.g., '-f 1 -wi 1 -i 3' for quick run)"
        required: false
        default: ""

permissions: {}

concurrency:
  group: "benchmarks"

defaults:
  run:
    shell: bash

jobs:
  benchmark:
    runs-on: ubuntu-26.04
    permissions:
      contents: read # checkout only
    steps:
      - name: Checkout main branch
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          persist-credentials: false
          fetch-depth: 0

      - name: Setup mise
        uses: jdx/mise-action@08ae2a091c038e1e05ec6f5115dc5c69d5a2a6b8 # v5.1.2
        with:
          version: v2026.10.2
          sha256: 8f5f6660336f572830e33cd9b378d3131e529a0d4c4f0c553776be90a1ba302a

      - name: Cache local Maven repository
        uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
        with:
          path: ~/.m2/repository
          key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
          restore-keys: |
            ${{ runner.os }}-maven-

      - name: Run JMH benchmarks
        run: mise run benchmark:ci-json
        env:
          JMH_ARGS: ${{ github.event.inputs.jmh_args }}

      - name: Generate benchmark summary
        run: |
          mise run benchmark:generate-summary \
            --input benchmark-results.json \
            --output-dir benchmark-results \
            --commit-sha "${{ github.sha }}"
        env:
          GITHUB_REPOSITORY: ${{ github.repository }}

      - name: Upload benchmark results
        uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
        with:
          name: benchmark-results
          path: benchmark-results
          retention-days: 5

  publish:
    runs-on: ubuntu-26.04
    needs: benchmark
    permissions:
      contents: write # push generated results to the benchmarks branch
    steps:
      - name: Checkout
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          # zizmor: ignore[artipacked] -- needs credentials to push to benchmarks branch
          persist-credentials: true
          fetch-depth: 0

      - name: Download benchmark results
        uses: actions/download-artifact@9000827ccba6bdab643e8b6fd33ac0654aef8333 # v8.0.2
        with:
          name: benchmark-results
          path: /tmp/benchmark-output

      - name: Commit and push results to benchmarks branch
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

          # Checkout or create benchmarks branch (use -- to disambiguate from benchmarks/ directory)
          if git ls-remote --heads origin benchmarks | grep -q benchmarks; then
            git fetch origin benchmarks
            git switch benchmarks
            # Preserve existing history
            if [ -d history ]; then
              cp -r history /tmp/benchmark-output/
            fi
          else
            git switch --orphan benchmarks
          fi

          # Clean working directory
          git rm -rf . 2>/dev/null || true
          find . -mindepth 1 -maxdepth 1 ! -name '.git' -exec rm -rf {} +

          # Copy only the benchmark results
          cp -r /tmp/benchmark-output/* .

          git add README.md results.json history/

          DATE=$(date -u +"%Y-%m-%d")
          COMMIT_SHORT=$(echo "${{ github.sha }}" | cut -c1-7)

          git commit \
            -m "Benchmark results for ${DATE} (${COMMIT_SHORT})" \
            -m "From commit ${{ github.sha }}" \
            || echo "No changes to commit"

          git push origin benchmarks --force-with-lease || git push origin benchmarks