private void waitForHealthyCluster() throws Exception {
        Map<String, String> params = new HashMap<>();
        params.put("wait_for_status", this.clusterHealthColor);
        params.put("timeout", "30s");

        elasticSearchAdminClient.performRequest("GET", "/_cluster/health", params);
    }
Waits for the ES cluster to become green.

@throws Exception If there is an issue connecting with the ES cluster.
es6-persistence/src/main/java/com/netflix/conductor/es6/dao/index/ElasticSearchRestDAOV6.java