@Test
public void testStateStoreUnavailable() throws IOException {

  curatorFramework.close();
  testingServer.stop();
  router.getStateStore().stop();
  // The driver is not ready
  assertFalse(router.getStateStore().isDriverReady());
  // Do a heartbeat, and no exception thrown out
  RouterHeartbeatService heartbeatService =
      new RouterHeartbeatService(router);
  heartbeatService.updateStateStore();
}