private List<MetricsValues> getMatcherMetricsValues(MatcherSetResult parseResult,  Duration duration) throws IOException {
        String metricName = parseResult.getMetricName();
        List<KeyValue> matchLabels = parseResult.getLabelMap().entrySet().stream().map(entry -> {
            KeyValue keyValue = new KeyValue();
            keyValue.setKey(entry.getKey());
            keyValue.setValue(entry.getValue());
            return keyValue;
        }).collect(Collectors.toList());

        return getMetricsQueryService().readLabeledMetricsValuesWithoutEntity(metricName, matchLabels, duration);
    }
OAP adopt time step by start/end,
reserve step/timeout param to keep consistent with API protocol.
oap-server/server-query-plugin/promql-plugin/src/main/java/org/apache/skywalking/oap/query/promql/handler/PromQLApiHandler.java