@RestController
@RequestMapping("system")
public class SystemController {

    private final ReactiveElasticsearchOperations operations;

    public SystemController(ReactiveElasticsearchOperations operations) {
        this.operations = operations;
    }

    @GetMapping("/cluster/health")
    public Mono<ClusterHealth> clusterHealth() {
        return operations.cluster().health();
    }
}

@RestController
@RequestMapping("system")
public class SystemController {

    private final ElasticsearchOperations operations;

    public SystemController(ElasticsearchOperations operations) {
        this.operations = operations;
    }

    @GetMapping("/cluster/health")
    public ClusterHealth clusterHealth() {
        return operations.cluster().health();
    }
}