check-pr-changelog.yml

name: Check if PR changelog was filled correctly
on:
    merge_group:
    pull_request:
      types: [opened, edited, synchronize, ready_for_review]

jobs:
  check-changelog:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/setup-node@v3
        with:
          node-version: 16
      - run: npm install js-yaml@4.1.0
      - name: Fail if PR changelog is not correct
        uses: actions/github-script@v6
        id: check-changelog
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const yaml = require('js-yaml');

            const prDescription = await github.rest.pulls.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: context.issue.number
            });

            const changelogRegex = /# Changelog([\s\S]*?)(?=\n#[^#])/;
            const changelogMatch = prDescription.data.body.match(changelogRegex);
            const changelogContent = changelogMatch ? changelogMatch [1].trim() : '';
          
            const yamlRegex = /```yaml([\s\S]*?)```/;
            const yamlMatch = changelogContent.match(yamlRegex);
            const yamlContent = yamlMatch ? yamlMatch[1].trim() : '';
          
            changelog = yaml.load(yamlContent)[0]

            let isCompatibilityValid = false;
            const validCompatibilityValues = ['no-api-changes', 'compatible', 'breaking'];
            if (Array.isArray(changelog.compatibility) && !!changelog.compatibility) {                
              isCompatibilityValid = changelog.compatibility.every(value => validCompatibilityValues.includes(value));
            } else {
              isCompatibilityValid = validCompatibilityValues.includes(changelog.compatibility);
            }
            if (!isCompatibilityValid) {
              console.error(`PR changelog has invalid compatibility: ${changelog.compatibility}\nExpected one, or more of: ${validCompatibilityValues}`)
            }

            let isTypeValid = false;
            const validTypeValues = ['feature', 'bugfix', 'test', 'maintenance'];;
            if (Array.isArray(changelog.type) && !!changelog.type) {                
              isTypeValid = changelog.type.every(value => validTypeValues.includes(value));
            } else {
              isTypeValid = validTypeValues.includes(changelog.type);
            }
            if (!isTypeValid) {
              console.error(`PR changelog has invalid type: ${changelog.type}\nExpected one, or more of: ${validTypeValues}`)
            }

            let isDescriptionValid = true;
            if (changelog.description.trim() === '<insert-changelog-description-here>') {
              console.error('PR changelog description has not been updated!')
              isDescriptionValid = false;
            } else if (!changelog.description.trim()) {
              console.error('PR changelog description field is missing!')
              isDescriptionValid = false;
            }

            if (!isCompatibilityValid || !isTypeValid || !isDescriptionValid) {
              console.error('Failed PR changelog checks!');
              process.exit(1);
            }