apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/controller/NamespaceController.java/NamespaceController/findNamespaces
class NamespaceController:  @GetMapping("/apps/{appId}/envs/{env}/clusters/{clusterName}/namespaces")
  public List<NamespaceBO> findNamespaces(@PathVariable String appId, @PathVariable String env,
                                          @PathVariable String clusterName) {

    List<NamespaceBO> namespaceBOs = namespaceService.findNamespaceBOs(appId, Env.valueOf(env), clusterName);

    for (NamespaceBO namespaceBO : namespaceBOs) {
      if (permissionValidator.shouldHideConfigToCurrentUser(appId, env, namespaceBO.getBaseInfo().getNamespaceName())) {
        namespaceBO.hideItems();
      }
    }

    return namespaceBOs;
  }