apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/controller/AccessKeyController.java/AccessKeyController/findByAppId
class AccessKeyController:  @PreAuthorize(value = "@permissionValidator.isAppAdmin(#appId)")
  @GetMapping(value = "/apps/{appId}/envs/{env}/accesskeys")
  public List<AccessKeyDTO> findByAppId(@PathVariable String appId,
      @PathVariable String env) {
    return accessKeyService.findByAppId(Env.valueOf(env), appId);
  }