create_comment.yaml

# This exists as a seperate workflow because pull_request workflows dont have permission to write comments

# How to use:
# 1. Add the name of the workflow that needs to leave a comment under on -> workflow_run -> workflows
# 2. In the main workflow always upload an artifact folder named comment_info
# 3. If a comment should be written then:
#    1. include issue_number.txt in the artifact folder containing the issue_number 
#    2. include message.txt in the artifact folder containing the message of the comment

name: Create Comment 

on:
  workflow_run:
    workflows: [ "Benchmarks" ]

# Cancel already running jobs
concurrency:
  group: create_comment_${{ github.head_ref }}
  cancel-in-progress: true

env:
  CARGO_TERM_COLOR: always
  RUST_BACKTRACE: 1

jobs:
  upload:
    runs-on: ubuntu-latest
    if: >
      ${{ github.event.workflow_run.event == 'pull_request' &&
      github.event.workflow_run.conclusion == 'success' }}
    steps:
      - name: 'Download results'
        uses: actions/download-artifact@v4
        with:
          name: 'comment-info'
          github-token: ${{ secrets.GITHUB_TOKEN }}
          run-id: ${{ github.event.workflow_run.id }}
      - run: unzip comment_info.zip
      - name: 'Comment on PR'
        uses: actions/github-script@v7
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            var fs = require('fs');
            if (fs.existsSync('./issue_number.txt')) {
              var issue_number = Number(fs.readFileSync('./issue_number.txt'));
              var message = fs.readFileSync('./message.txt', 'utf8');
              await github.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: issue_number,
                body: message,
              });
            }