public String reqApi(String api, Map<String, String> params, String method) throws NacosException {
        return reqApi(api, params, Collections.EMPTY_MAP, method);
    }
@Test
    void testReqApiForEmptyServer() throws NacosException {
        assertThrows(NacosException.class, () -> {
            Map<String, String> params = new HashMap<>();
            clientProxy.reqApi("api", params, Collections.emptyMap(), Collections.emptyList(), HttpMethod.GET);
        });
    }