public String loadComputeNodeState(final String instanceId) {
        return repository.query(ComputeNode.getComputeNodeStateNodePath(instanceId));
    }
@Test
    void assertLoadComputeNodeState() {
        InstanceMetaData instanceMetaData = new ProxyInstanceMetaData("foo_instance_id", 3307);
        final String instanceId = instanceMetaData.getId();
        new ComputeNodePersistService(repository).loadComputeNodeState(instanceId);
        verify(repository).query(ComputeNode.getComputeNodeStateNodePath(instanceId));
    }