issue_lock.yml

name: issue_lock

on:
  schedule:
  - cron: '40 15 * * *'
  workflow_dispatch:

jobs:
  issue_lock:
    runs-on: ubuntu-latest

    steps:
    - uses: actions/github-script@v6
      with:
        github-token: ${{ secrets.GITHUB_TOKEN }}
        script: |
          const { repo: { owner, repo } } = context;

          const now = new Date();

          for await (const res of github.paginate.iterator(
              github.rest.issues.listForRepo, {
                owner,
                repo,
                state: 'closed',
          })) {
            for (const issue of res.data) {
              if (issue.locked) {
                continue;
              }

              if ((now - new Date(issue.updated_at)) < 1000*60*60*24*31*6) {
                continue;
              }

              if (!issue.pull_request) {
                await github.rest.issues.createComment({
                  owner,
                  repo,
                  issue_number: issue.number,
                  body: 'This issue is being locked automatically because it has been closed for more than 6 months.\n'
                    + 'Please open a new issue in case you encounter a similar problem.',
                });
              }

              github.rest.issues.lock({
                owner,
                repo,
                issue_number: issue.number,
              });
            }
          }