SukkaSurge/Build/lib/is-domain-loose.js

// @ts-check
const tldts = require('./cached-tld-parse');

/**
 * @param {string} domain
 */
module.exports.isDomainLoose = (domain) => {
  const { isIcann, isPrivate, isIp } = tldts.parse(domain);
  return !!(!isIp && (isIcann || isPrivate));
};

/**
 * @param {string} domain
 */
module.exports.normalizeDomain = (domain) => {
  if (domain == null) {
    return null;
  }

  const { isIcann, isPrivate, hostname, isIp } = tldts.parse(domain);
  if (isIp) {
    return null;
  }

  if (isIcann || isPrivate) {
    if (hostname?.[0] === '.') {
      return hostname.slice(1);
    }
    return hostname;
  }

  return null;
};