pr-benchdiff.yml

name: Benchdiff

on:
  issue_comment:
    types: [created]
  pull_request:
    types: [opened]
    paths-ignore:
      - '**.md'

jobs:
  # https://github.community/t/cancelling-rest-of-job-if-condition-is-met/18181
  trigger:
    name: Pull request comment trigger
    outputs:
      triggered: ${{ steps.output.outputs.triggered }}
      pr_number: ${{ steps.output.outputs.pr_number }}
    runs-on: self-hosted
    steps:
      - name: Check pull request comment
        if: ${{ github.event_name == 'issue_comment' }}
        uses: khan/pull-request-comment-trigger@master
        id: check-comment
        with:
          trigger: '/benchdiff'
        env:
          GITHUB_TOKEN: '${{ secrets.GITHUB_TOKEN }}'
      - name: Set output
        id: output
        run: |
          echo '::set-output name=triggered::${{ github.event_name == 'pull_request' || steps.check-comment.outputs.triggered }}'
          echo '::set-output name=pr_number::${{ github.event.pull_request.number || github.event.issue.number }}'

  benchdiff:
    name: Performance regression check
    needs: [trigger]
    if: needs.trigger.outputs.triggered == 'true'
    runs-on: self-hosted
    env:
      # In markdown URL syntax
      RUNS_URL: '[${{ github.workflow }} #${{ github.run_number }}](https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }})'
    steps:
      - name: Report job start
        uses: peter-evans/create-or-update-comment@v1
        with:
          issue-number: '${{ needs.trigger.outputs.pr_number }}'
          body: |
            ## Benchdiff

            Runs: ${{ env.RUNS_URL }}

            Job is started.
      - name: Checkout
        uses: actions/checkout@v2
      - name: Checkout pull request HEAD
        id: head
        run: |
          # Fetch github default branch as baseline
          git fetch origin ${{ github.event.repository.default_branch }}:BENCHDIFF_BASE
          git checkout BENCHDIFF_BASE
          echo "::set-output name=base::$(git rev-parse HEAD)"

          # Checkout HEAD of pull request and set its sha to step output
          git fetch origin pull/${{ needs.trigger.outputs.pr_number }}/head:BENCHDIFF_HEAD
          git checkout BENCHDIFF_HEAD
          echo "::set-output name=head::$(git rev-parse HEAD)"

          set -x
          # Set modified packages to step output
          # git diff: get difference between HEAD and baseline
          # grep: filter non-go files
          # xargs -r: --no-run-if-empty, ignore empty line
          # xargs dirname: keep only the directory name (go packages)
          # xargs ls: filter non-exist files
          # sort | uniq: dedup
          pkgs=$(git diff --name-only BENCHDIFF_BASE | grep '.go$' | xargs -r dirname | xargs -r ls -d 2>/dev/null | sort | uniq)
          if [ ! -z "${pkgs}" ]; then
            # awk: Add "./" prefix to let `go test` known they are relative paths
            # tr: join paths to one line, otherwise benchdiff cannot recognize it
            pkgs=$(echo "${pkgs}" | awk '{print "./" $0}' | tr '\n' ' ')
          fi
          echo "::set-output name=pkgs::${pkgs}"
      - name: Setup go
        uses: actions/setup-go@v2
        with:
          go-version: 1.17
      - name: Benchdiff
        uses: WillAbides/benchdiff-action@v0.3.3
        id: diff
        if: steps.head.outputs.pkgs != ''
        with:
          benchdiff_version: 0.7.1
          status_sha: ${{ steps.head.outputs.head }}
          status_name: Benchdiff result
          status_on_degraded: neutral
          benchdiff_args: |
            --cpu=4
            --packages="${{ steps.head.outputs.pkgs }}"
            --count=10
            --warmup-count=1
            --benchtime=1s
            --benchmem
            --tolerance=50
            --base-ref=${{ steps.head.outputs.base }}
            --debug
      - name: Report benchdiff result via comment
        uses: peter-evans/create-or-update-comment@v1
        if: steps.head.outputs.pkgs != ''
        with:
          issue-number: '${{ needs.trigger.outputs.pr_number }}'
          body: |
            ## Benchdiff

            Command: `${{ steps.diff.outputs.bench_command }}`
            HEAD: ${{ steps.diff.outputs.head_sha }}
            Base: ${{ steps.diff.outputs.base_sha }}
            Runs: ${{ env.RUNS_URL }}
            Degraded: ${{ steps.diff.outputs.degraded_result }}

            <details>
            <summary>Results</summary>

            ${{ steps.diff.outputs.benchstat_output }}

            </details>
      - name: On skipped
        uses: peter-evans/create-or-update-comment@v1
        if: steps.head.outputs.pkgs == ''
        with:
          issue-number: '${{ needs.trigger.outputs.pr_number }}'
          body: |
            ## Benchdiff

            Runs: ${{ env.RUNS_URL }}

            There is no package to bench.
      - name: On failure
        uses: peter-evans/create-or-update-comment@v1
        if: ${{ failure() }}
        with:
          issue-number: '${{ needs.trigger.outputs.pr_number }}'
          body: |
            ## Benchdiff

            Runs: ${{ env.RUNS_URL }}

            Job is failed.