@Override
    public String toString() {
        return new StringJoiner(", ", EsMetricsClientOptionsParser.class.getSimpleName() + "[", "]")
                .add("requestHeaders=" + requestHeaders)
                .add("responseHeaders=" + responseHeaders)
                .add("queryParams=" + queryParams)
                .add("writeTo=" + writeTo)
                .toString();
    }
Options parser for Elasticsearch metrics

@author Marc Savy {@literal <marc@blackparrotlabs.io>}
gateway/engine/es/src/main/java/io/apiman/gateway/engine/es/EsMetricsClientOptionsParser.java