docs: function saveItemService(app) {
      apiService.call(this);
      this.setApp(app);
  
      var service = this;
  
      /**
       * Test required fields in params
       * complete outcome and http status if a fields is empty
       *
       * @param {Object} params - parameters to save
       * @param {Array} list - list of fields to test
       *
       * @return {bool}
       */
      service.needRequiredFields = function(params, list) {
  
          for(var i=0; i<list.length; i++)
          {
              if (!params[list[i]]) {
                  service.outcome.errfor[list[i]] = 'required';
                  service.httpstatus = 400; // Bad Request
                  service.outcome.success = false;
              }
          }
  
          if (service.hasErrors()) {
              service.deferred.reject(new Error('Missing mandatory fields'));
              return true;
          }
  
          return false;
      };
  }