code: function (msg) {
          var ids = payloadIndex.query(msg);
  
          if (ids.length === 0) {
              return;
          }
  
          var payload = payloads[ids[0]];
  
          if (ids.length > 1) {
              for (var i = 1; i < ids.length; ++i) {
                  payload = external.merge(innerPay, fpay);
              }
          }
  
          return payload;
      }
docs: /*
  Private APIs