add-hacktoberfest-labels.yml

name: Propagate Issue Labels to PR

on:
  pull_request:
    types: [opened, synchronize]

jobs:
  copy_labels:
    runs-on: ubuntu-latest
    steps:
    - name: Checkout
      uses: actions/checkout@v4

    - name: Get issue number from PR body
      id: issue_number
      run: |
        issue_number=$(echo "${{ github.event.pull_request.body }}" | grep -oP '(?<=#)\d+' | head -n1)
        if [ -z "$issue_number" ]; then
          echo "No issue number found in PR body"
          echo "has_issue=false" >> $GITHUB_OUTPUT
        else
          echo "Issue number found: $issue_number"
          echo "has_issue=true" >> $GITHUB_OUTPUT
          echo "issue_number=$issue_number" >> $GITHUB_OUTPUT
        fi

    - name: Get labels from linked issue
      if: steps.issue_number.outputs.has_issue == 'true'
      uses: actions/github-script@v6
      id: issue_labels
      with:
        github-token: ${{ secrets.GITHUB_TOKEN }}
        script: |
          const issue_number = ${{ steps.issue_number.outputs.issue_number }};
          try {
            const issue = await github.rest.issues.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: parseInt(issue_number)
            });
            return issue.data.labels.map(label => label.name);
          } catch (error) {
            console.log(`Error fetching issue labels: ${error}`);
            return [];
          }

    - name: Check for required labels
      if: steps.issue_number.outputs.has_issue == 'true' && steps.issue_labels.outputs.result != '[]'
      id: check_labels
      uses: actions/github-script@v6
      with:
        github-token: ${{ secrets.GITHUB_TOKEN }}
        script: |
          const labels = ${{ steps.issue_labels.outputs.result }};
          const hacktoberfestLabel = labels.some(label => label.toLowerCase().includes('hacktoberfest'));
          const sizeLabelPresent = labels.some(label => ['small', 'medium', 'large'].includes(label.toLowerCase()));
          return hacktoberfestLabel || sizeLabelPresent;

    - name: Add labels to PR
      if: steps.issue_number.outputs.has_issue == 'true' && steps.check_labels.outputs.result == 'true'
      uses: actions/github-script@v6
      with:
        github-token: ${{ secrets.GITHUB_TOKEN }}
        script: |
          const pr_number = context.issue.number;
          const labels = ${{ steps.issue_labels.outputs.result }};
          try {
            await github.rest.issues.addLabels({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: pr_number,
              labels: labels
            });
            console.log('Labels added successfully');
          } catch (error) {
            console.log(`Error adding labels: ${error}`);
          }