permuteDomain.js

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"use strict";
var pubsuffix = require('./pubsuffix');

// Gives the permutation of all possible domainMatch()es of a given domain. The
// array is in shortest-to-longest order.  Handy for indexing.
function permuteDomain (domain) {
  var pubSuf = pubsuffix.getPublicSuffix(domain);
  if (!pubSuf) {
    return null;
  }
  if (pubSuf == domain) {
    return [domain];
  }

  var prefix = domain.slice(0, -(pubSuf.length + 1)); // ".example.com"
  var parts = prefix.split('.').reverse();
  var cur = pubSuf;
  var permutations = [cur];
  while (parts.length) {
    cur = parts.shift() + '.' + cur;
    permutations.push(cur);
  }
  return permutations;
}

exports.permuteDomain = permuteDomain;