// Helper method to create mock ClusterHealthResponse
    private ClusterHealthResponse createMockHealthResponse(String clusterName, ClusterHealthStatus status) {
        return new ClusterHealthResponse() {
            @Override
            public String getClusterName() {
                return clusterName;
            }

            @Override
            public ClusterHealthStatus getStatus() {

            final ClusterHealthResponse response =
                    esClient.admin().cluster().prepareHealth().execute().actionGet(fessConfig.getIndexHealthTimeout());
            engineObj.clusterName = response.getClusterName();
            engineObj.numberOfNodes = response.getNumberOfNodes();
            engineObj.numberOfDataNodes = response.getNumberOfDataNodes();