pull-request.yaml

name: Pull Request
on:
  pull_request_target:
    # make sure that when the PR changes, we also update
    types:
      - opened
      - edited
      - synchronize
      - reopened

permissions:
  pull-requests: write
  issues: write

jobs:
  conventional-commit-labeler:
    name: Label PR based on Conventional Commit Specification
    permissions:
      contents: read
      pull-requests: write
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v7
        env:
          TYPE_TO_LABEL: |
            {
              "feat":"kind/feature",
              "fix":"kind/bugfix",
              "chore":"kind/chore",
              "docs":"area/documentation",
              "test":"area/testing",
              "perf":"area/performance"
            }
          SCOPE_TO_LABEL: |
            {
              "deps":"kind/dependency"
            }
          BREAKING_CHANGE_LABEL: "!BREAKING-CHANGE!"
        with:
          script: |
            console.log("Verify that the PR title follows the Conventional Commit format");

            // Parse mappings from environment variables
            const typeToLabel = JSON.parse(process.env.TYPE_TO_LABEL);
            const scopeToLabel = JSON.parse(process.env.SCOPE_TO_LABEL);
            console.log("Type-to-Label Mapping:", typeToLabel);
            console.log("Scope-to-Label Mapping:", scopeToLabel);

            // Dynamically generate allowed types
            const allowedTypes = Object.keys(typeToLabel).join('|');
            console.log(`Allowed Types: ${allowedTypes}`);
            
            const prTitle = context.payload.pull_request.title;
            console.log(`PR Title: ${prTitle}`);
            
            // We know this regex looks scary, but it's just to match the Conventional Commit format
            // It parses out a Title into several named regex groups, which we can use to extract various semantic patterns:
            // - type: The type of change (feat, fix, etc.)
            // - scope: The scope of the change (optional and set in brackets)
            // - breaking: A flag to indicate a breaking change (!)
            // - subject: The subject of the change
            // Example: feat(scope)!: add new feature
            //          ^^^^ ^^^^^ ^  ^^^^^^^^^^^^^^^
            //          type scope    subject
            const regex = new RegExp(
            `^(((Initial commit)|(Merge [^\\r\\n]+(\\s)[^\\r\\n]+((\\s)((\\s)[^\\r\\n]+)+)*(\\s)?)|^((?<type>${allowedTypes})(\\((?<scope>[\\w\\-]+)\\))?(?<breaking>!?): (?<subject>[^\\r\\n]+((\\s)((\\s)[^\\r\\n]+)+)*))(\\s)?)$)`
            );
            console.log(`Regex: ${regex}`);
  
            const match = prTitle.match(regex);
            console.log(`Match: ${match != null}`);
            
            if (match && match.groups) {
              const { type, scope, breaking } = match.groups;

              // Initialize labels array
              const labels = [];
            
              if (breaking) {
                console.log("Adding breaking change label");
                labels.push(process.env.BREAKING_CHANGE_LABEL);
              }

              // Add type-based label
              if (type && typeToLabel[type]) {
                labels.push(typeToLabel[type]);
              } else {
                console.log(`No label found for type: ${type}`);
              }

              // Add scope-based label if scope exists
              if (scope && scopeToLabel[scope]) {
                labels.push(scopeToLabel[scope]);
              } else if (scope) {
                console.log(`No label found for scope: ${scope}`);
              }

              if (labels.length > 0) {
                console.log(`Adding labels: ${labels}`);
                await github.rest.issues.addLabels({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: context.payload.pull_request.number,
                  labels: labels,
                });
              } else {
                console.log("No labels to add.");
              }
            } else {
              console.log("Invalid PR title format. Make sure you named the PR after the specification at https://www.conventionalcommits.org/en/v1.0.0/#specification. Exiting...");
              process.exit(1);
            }
  labeler:
    name: Label PR based on Config
    permissions:
      contents: read
      pull-requests: write
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          sparse-checkout: |
            .github/config/labeler.yml
      - uses: actions/labeler@v5
        with:
          configuration-path: .github/config/labeler.yml
  size-labeler:
    runs-on: ubuntu-latest
    name: Label PR based on size
    permissions:
      issues: write
      pull-requests: write
    steps:
      - uses: codelytv/pr-size-labeler@v1
        with:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          xs_label: 'size/xs'
          xs_max_size: '10'
          s_label: 'size/s'
          s_max_size: '100'
          m_label: 'size/m'
          m_max_size: '500'
          l_label: 'size/l'
          l_max_size: '10000'
          xl_label: 'size/xl'
          fail_if_xl: 'true'
          message_if_xl: >
            This PR exceeds the recommended size of 10000 lines.
            Please make sure you are NOT addressing multiple issues with one PR.
            Note this PR might be rejected due to its size.
          # github_api_url: 'api.github.com'
          # files_to_ignore: ''
  verify-labels:
    needs: [labeler, size-labeler, conventional-commit-labeler]
    name: verify labels
    runs-on: ubuntu-latest
    steps:
      - name: PRs should have at least one qualifying label
        uses: docker://agilepathway/pull-request-label-checker:latest
        with:
          any_of: kind/chore,kind/bugfix,kind/feature,kind/dependency,kind/refactor
          repo_token: ${{ secrets.GITHUB_TOKEN }}