public void updateComputeNodeState(final String instanceId, final InstanceState instanceState) {
        repository.persistEphemeral(ComputeNode.getComputeNodeStateNodePath(instanceId), instanceState.name());
    }
@Test
    void assertUpdateComputeNodeState() {
        new ComputeNodePersistService(repository).updateComputeNodeState("foo_instance_id", InstanceState.OK);
        verify(repository).persistEphemeral(ComputeNode.getComputeNodeStateNodePath("foo_instance_id"), InstanceState.OK.name());
    }