How to use the tldts-experimental.getDomain function in tldts-experimental

page.on('request', onRequest);

          console.log(`  * goto: ${urlToVisit}`);
          const status = await page.goto(urlToVisit, {
            timeout: 120000,
            waitUntil: 'networkidle2',
          });

          const pageUrl = page.url();
          if (pageUrl !== urlToVisit) {
            console.log(`    > ${page.url()}`);
          }

          // We do not collect URLs unless we are on the home-page
          if (status.ok && url === undefined) {
            const domainOfPage = getDomain(pageUrl);
            const urlsOnPage = await page.evaluate(() => [...document.querySelectorAll('a')].map(a => a.href).filter(Boolean));
            const sameDomainUrls = urlsOnPage.filter(
              href => href
                && (href.startsWith('https://')
                  || href.startsWith('http://')
                  || href.startsWith('ws://')
                  || href.startsWith('wss://'))
                && getDomain(href) === domainOfPage,
            );
            return [...new Set(sameDomainUrls)];
          }
        } catch (ex) {
          console.log(`Could not fetch: ${urlToVisit}`, ex);
        } finally {
          await page.removeAllListeners('request');
          await page.close();

const { cpt, sourceUrl, url } = request;

    if (cpt === 'document' || url.length > 200) {
      return;
    }

    const t0 = Date.now();
    const { exception, filter } = engine.match({
      cpt: cpt.toLowerCase(),
      sourceUrl,
      url,
    });

    const total = Date.now() - t0;
    const sourceDomain = getDomain(sourceUrl);

    if (total > 5) {
      console.log('SLOW', total, cpt, sourceUrl, url.slice(0, 25), '...');
      slowRequests.push(request);
    }

    if (filter !== undefined && !networkFilters.has(filter.rawLine)) {
      networkFilters.add(filter.rawLine);
      // console.log('> f', removeExtraHostnames(filter));
      addFilter(sourceDomain, removeExtraHostnames(filter));
    }

    if (exception !== undefined && !networkFilters.has(exception.rawLine)) {
      networkFilters.add(exception.rawLine);
      // console.log('> e', removeExtraHostnames(exception));
      addFilter(sourceDomain, removeExtraHostnames(exception));

href => href
                && (href.startsWith('https://')
                  || href.startsWith('http://')
                  || href.startsWith('ws://')
                  || href.startsWith('wss://'))
                && getDomain(href) === domainOfPage,
            );