maintainers-tsc-changes-verification.yaml

name: Verify tsc and maintainers changes by human and bot

on:
  pull_request:
    types: [synchronize, opened, reopened]
    paths:
      - "MAINTAINERS.yaml"
env:
  GITHUB_TOKEN: ${{ secrets.GH_TOKEN }}

jobs:
  verify-changes-if-tsc-if-maintainers:
    # if statement to check if the PR is open.
    if: github.event.pull_request.state == 'open'
    runs-on: ubuntu-latest

    steps:
      - name: Checkout main branch
        uses: actions/checkout@v3
        with:
          ref: master
          path: community-main

      - name: Checkout PR branch
        uses: actions/checkout@v3
        with:
          ref: ${{github.event.pull_request.head.ref}}
          repository: ${{github.event.pull_request.head.repo.full_name}}
          path: pr-branch

      - name: Install js-yaml
        run: npm install js-yaml@4.1.0

      - name: Verify changes in MAINTAINERS.yaml
        id: verify-changes
        uses: actions/github-script@v6
        with:
          github-token: ${{ env.GITHUB_TOKEN }}
          script: |
            const yaml = require("js-yaml");
            const fs = require("fs");

            const mainFile = yaml.load(fs.readFileSync("./community-main/MAINTAINERS.yaml", "utf8"));
            const prFile = yaml.load(fs.readFileSync("./pr-branch/MAINTAINERS.yaml", "utf8"));

            const beforeMaintainers = new Map(mainFile.map((maintainer) => [maintainer.name, {github: maintainer.github, repos: maintainer.repos || []}]));
            let errorMessages = [];

            const owner = context.repo.owner;
            const repo = context.repo.repo;
            const pull_number = context.issue.number;
            const author = context.payload.pull_request.user.login;
            let removedTscMembers = [];

            // If the PR is made by the bot.
            if (author === 'asyncapi-bot') {
              core.info('Changes made by asyncapi-bot')
              core.setOutput('errorMessages', JSON.stringify(errorMessages));

              const removedMaintainers = mainFile.filter(
                (mainMaintainer) => !prFile.some((maintainer) => mainMaintainer.github === maintainer.github)
              );
              removedTscMembers = removedMaintainers.filter(maintainer => maintainer.isTscMember);

              if (removedTscMembers.length > 0) {
                core.setOutput("removedTscMembers", JSON.stringify(removedTscMembers));
              }
              else {
                return
              }
            }

            // detecting if changes in the PR contain removal of maintainer object 
            if (prFile.length < mainFile.length) {
              errorMessages.push('A maintainer has been removed from `MAINTAINERS.yaml` file. Only `asyncapi-bot` can make such changes. Maintainers are removed from the file in an automated way only if they are no longer mentioned in `CODEOWNERS` file in any repository under AsyncAPI GitHub organization.');
            }

            for (const maintainer of prFile) {
              // retrieve the previous data of the maintainer from the main file
              const previousData = beforeMaintainers.get(maintainer.name);
              // if the maintainer is not found in the previous data, it is a new maintainer 
              if (!previousData) {
                errorMessages.push(`A new maintainer, ${maintainer.name}, has been added to MAINTAINERS.yaml. Only asyncapi-bot can make such changes. Maintainers are added to the file in an automated way only if they are mentioned in the CODEOWNERS file in any repository under AsyncAPI GitHub organization.`);
              } else {
                // retrieve the previous GitHub key and repositories of the maintainer
                const previousGithub = previousData.github;
                const previousRepos = previousData.repos;
                // check if the GitHub key for the maintainer has been modified
                if (previousGithub !== maintainer.github) {
                  errorMessages.push(`GitHub key for ${maintainer.name} has been modified in MAINTAINERS.yaml. Only asyncapi-bot can make such changes. This information is derived from the CODEOWNERS file located in any repository under AsyncAPI GitHub organization.`);
                }
                // check if the repositories list for the maintainer has been modified
                if (previousRepos.toString() !== (maintainer.repos || []).toString()) {
                  // Check if a human added a repo to the maintainer's repository list
                  const previousReposLength = previousData.repos.length;
                  const currentReposLength = (maintainer.repos || []).length;                
                  // Check if a repository is added by a human
                  if (currentReposLength > previousReposLength) {
                    const addedRepos = (maintainer.repos || []).slice(previousReposLength);
                    errorMessages.push(`New repositories (${addedRepos.join(', ')}) have been added to ${maintainer.name}'s repository list in MAINTAINERS.yaml. Only asyncapi-bot can make such changes. This information is derived from the CODEOWNERS file located in any repository under AsyncAPI GitHub organization.`);
                  }
                  // Check if a repository is removed by a human
                  if (currentReposLength < previousReposLength) {
                    const removedRepos = previousData.repos.slice(currentReposLength);
                    errorMessages.push(`Repositories (${removedRepos.join(', ')}) have been removed from ${maintainer.name}'s repository list in MAINTAINERS.yaml. Only asyncapi-bot can make such changes. This information is derived from the CODEOWNERS file located in any repository under AsyncAPI GitHub organization.`);
                  }
                }
              }
            }
            // Console log the error messages
            core.info('Error messages:', errorMessages);
            // Set the error messages as an output
            core.info('Setting error messages output...');
            core.setOutput('errorMessages', JSON.stringify(errorMessages));

    outputs: 
      errorMessages: ${{ steps.verify-changes.outputs.errorMessages }}
      removedTscMembers: ${{ steps.verify-changes.outputs.removedTscMembers }}

  block-human-made-critical-changes:
    needs: verify-changes-if-tsc-if-maintainers
    if: needs.verify-changes-if-tsc-if-maintainers.outputs.errorMessages != '[]'
    runs-on: ubuntu-latest
    steps:
      - name: Comment and close the PR if there are any critical changes done by human
        uses: actions/github-script@v6
        with:
          github-token: ${{ env.GITHUB_TOKEN }}
          script: |
            const errorMessagesString = `${{ needs.verify-changes-if-tsc-if-maintainers.outputs.errorMessages }}`;
            const errorMessages = errorMessagesString ? JSON.parse(errorMessagesString) : [];
            console.log('Parsed errorMessages:', errorMessages);
            if (errorMessages && Array.isArray(errorMessages) && errorMessages.length > 0) {
              const owner = context.repo.owner;
              const repo = context.repo.repo;
              const pull_number = context.issue.number;
              const commentBody = errorMessages[0];
              const commentContext = {
                owner: owner,
                repo: repo,
                issue_number: pull_number,
                body: commentBody
              };
              github.rest.issues.createComment(commentContext);
              github.rest.pulls.update({
                owner: owner,
                repo: repo,
                pull_number: pull_number,
                state: 'closed'
              });
            } else {
              console.info('errorMessages is empty.');
            }

  block-bot-from-tsc-removal:
    needs: verify-changes-if-tsc-if-maintainers
    if:  needs.verify-changes-if-tsc-if-maintainers.outputs.removedTscMembers !=  ''
    runs-on: ubuntu-latest
    steps:
      - name: Comment on PR if TSC member is removed by asyncapi-bot
        if: steps.verify-changes-if-tsc-if-maintainers.outputs.removedTscMembers != ''
        uses: actions/github-script@v6
        with:
          github-token: ${{ env.GITHUB_TOKEN }}
          script: |
              const issueComment = {
                  owner: github.context.repo.owner,
                  repo: github.context.repo.repo,
                  issue_number: github.context.issue.number,
                  body: 'A TSC member has been removed in this PR. Maintainers of this repository need to review and approve this PR.'
              }
              
              const addLabel = {
                  owner: github.context.repo.owner,
                  repo: github.context.repo.repo,
                  issue_number: github.context.issue.number,
                  labels: ['do-not-merge']
              }
              
              github.rest.issues.createComment(issueComment);
              github.rest.issues.addLabels(addLabel);