regQ(queryBuilder);
    }

    public void queryString(String queryString) {
        checkEsInvalidQuery("queryString", queryString);
        doQueryString(queryString, null);
    }

    public void queryString(String queryString, ConditionOptionCall<QueryStringQueryBuilder> opLambda) {
        checkEsInvalidQuery("queryString", queryString);
        assertObjectNotNull("opLambda", opLambda);

        regQ(queryBuilder);
    }

    public void queryString(String queryString) {
        checkEsInvalidQuery("queryString", queryString);
        doQueryString(queryString, null);
    }

    public void queryString(String queryString, ConditionOptionCall<QueryStringQueryBuilder> opLambda) {
        checkEsInvalidQuery("queryString", queryString);
        assertObjectNotNull("opLambda", opLambda);

        regQ(queryBuilder);
    }

    public void queryString(String queryString) {
        checkEsInvalidQuery("queryString", queryString);
        doQueryString(queryString, null);
    }

    public void queryString(String queryString, ConditionOptionCall<QueryStringQueryBuilder> opLambda) {
        checkEsInvalidQuery("queryString", queryString);
        assertObjectNotNull("opLambda", opLambda);

    }

    protected static void deleteDocuments(final String queryString) {
        List<String> docIds = new ArrayList<>();
        Response response = given().contentType("application/json").param("scroll", "1m").param("q", queryString)
                .get(getEsUrl() + "/" + DOC_INDEX_NAME + "/_search");
        JsonPath jsonPath = JsonPath.from(response.asString());

        final String urlField = fessConfig.getIndexFieldUrl();
        final String queryString = "*" + text + "*";
        context.addFieldLog(urlField, queryString);
        context.addHighlightedQuery(text);
        return QueryBuilders.wildcardQuery(urlField, queryString).boost(boost);
    }

// must be extracted from the header.
var userMetadataKeyPrefixes = []string{
	"x-amz-meta-",
	"x-minio-meta-",
}

// extractMetadataFromReq extracts metadata from HTTP header and HTTP queryString.
func extractMetadataFromReq(ctx context.Context, r *http.Request) (metadata map[string]string, err error) {
	return extractMetadata(ctx, textproto.MIMEHeader(r.Form), textproto.MIMEHeader(r.Header))
}