code: function onEntity(entityDataFetched) {
              const entityData = arrify(entityDataFetched);
  
              if (ids.length === 1
                  && (entityData.length === 0 || typeof entityData[0] === 'undefined' || entityData[0] === null)) {
                  if (_this.gstore.config.errorOnEntityNotFound) {
                      return Promise.reject(new GstoreError(
                          errorCodes.ERR_ENTITY_NOT_FOUND,
                          `${_this.entityKind} { ${ids[0].toString()} } not found`
                      ));
                  }
  
                  return null;
              }
  
              const entity = entityData
                  .map((data) => {
                      if (typeof data === 'undefined' || data === null) {
                          return null;
                      }
                      return _this.__model(data, null, null, null, data[_this.gstore.ds.KEY]);
                  });
  
              if (Array.isArray(id)
                && options.preserveOrder
                && entity.every(e => typeof e !== 'undefined' && e !== null)) {
                  entity.sort((a, b) => id.indexOf(a.entityKey.id) - id.indexOf(b.entityKey.id));
              }
  
              return Array.isArray(id) ? entity : entity[0];
          }
docs: ----------