apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/controller/ItemController.java/ItemController/findItems
class ItemController:  @GetMapping("/apps/{appId}/envs/{env}/clusters/{clusterName}/namespaces/{namespaceName}/items")
  public List<ItemDTO> findItems(@PathVariable String appId, @PathVariable String env,
                                 @PathVariable String clusterName, @PathVariable String namespaceName,
                                 @RequestParam(defaultValue = "lineNum") String orderBy) {

    if (permissionValidator.shouldHideConfigToCurrentUser(appId, env, namespaceName)) {
      return Collections.emptyList();
    }

    List<ItemDTO> items = configService.findItems(appId, Env.valueOf(env), clusterName, namespaceName);
    if ("lastModifiedTime".equals(orderBy)) {
      items.sort((o1, o2) -> {
        if (o1.getDataChangeLastModifiedTime().after(o2.getDataChangeLastModifiedTime())) {
          return -1;
        }
        if (o1.getDataChangeLastModifiedTime().before(o2.getDataChangeLastModifiedTime())) {
          return 1;
        }
        return 0;
      });
    }
    return items;
  }