bot-28/node/node_modules/validator/es/lib/isFQDN.js

import assertString from './util/assertString';
import merge from './util/merge';
var default_fqdn_options = {
  require_tld: true,
  allow_underscores: false,
  allow_trailing_dot: false,
  allow_numeric_tld: false,
  allow_wildcard: false,
  ignore_max_length: false
};
export default function isFQDN(str, options) {
  assertString(str);
  options = merge(options, default_fqdn_options);

  /* Remove the optional trailing dot before checking validity */
  if (options.allow_trailing_dot && str[str.length - 1] === '.') {
    str = str.substring(0, str.length - 1);
  }

  /* Remove the optional wildcard before checking validity */
  if (options.allow_wildcard === true && str.indexOf('*.') === 0) {
    str = str.substring(2);
  }
  var parts = str.split('.');
  var tld = parts[parts.length - 1];
  if (options.require_tld) {
    // disallow fqdns without tld
    if (parts.length < 2) {
      return false;
    }
    if (!options.allow_numeric_tld && !/^([a-z\u00A1-\u00A8\u00AA-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]{2,}|xn[a-z0-9-]{2,})$/i.test(tld)) {
      return false;
    }

    // disallow spaces
    if (/\s/.test(tld)) {
      return false;
    }
  }

  // reject numeric TLDs
  if (!options.allow_numeric_tld && /^\d+$/.test(tld)) {
    return false;
  }
  return parts.every(function (part) {
    if (part.length > 63 && !options.ignore_max_length) {
      return false;
    }
    if (!/^[a-z_\u00a1-\uffff0-9-]+$/i.test(part)) {
      return false;
    }

    // disallow full-width chars
    if (/[\uff01-\uff5e]/.test(part)) {
      return false;
    }

    // disallow parts starting or ending with hyphen
    if (/^-|-$/.test(part)) {
      return false;
    }
    if (!options.allow_underscores && /_/.test(part)) {
      return false;
    }
    return true;
  });
}