cacheResponse.js

app.factory(‘Items’,function($http) {
  var items = [];
  return {
    list: function() {
      var defer=$q.defer();
      if (items.length == 0) { // items array is empty so populate it and return list from server to controller
         $http.get(‘/?items’).then(function(response) {
         items = response.data.items;
         defer.resolve(items);
         });
      }
      else {
          defer.resolve(items);
      }
      return defer.promise;
    }
  }