@Override
  public SettableFuture<ConfigTaskResult> showModels(final String modelName) {
    final SettableFuture<ConfigTaskResult> future = SettableFuture.create();
    try (final ConfigNodeClient client =
        CONFIG_NODE_CLIENT_MANAGER.borrowClient(ConfigNodeInfo.CONFIG_REGION_ID)) {
      final TShowModelReq req = new TShowModelReq();
      if (modelName != null) {
        req.setModelId(modelName);
      }
      final TShowModelResp showModelResp = client.showModel(req);
      if (showModelResp.getStatus().getCode() != TSStatusCode.SUCCESS_STATUS.getStatusCode()) {
        future.setException(
            new IoTDBException(showModelResp.getStatus().message, showModelResp.getStatus().code));
        return future;
      }
      // convert model info list and buildTsBlock
      ShowModelsTask.buildTsBlock(showModelResp.getModelInfoList(), future);
    } catch (final ClientManagerException | TException e) {
      future.setException(e);
    }
    return future;
  }
FIXME Consolidate this clientManager with the upper one.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/execution/config/executor/ClusterConfigTaskExecutor.java