public Optional<List<SampleFamily>> metricsContainer() {
        // noinspection unchecked
        return Optional.ofNullable((List<SampleFamily>) getProperty(KEY_METRICS_CONTAINER));
    }
Set the metrics container to store all metrics generated from the pipeline,
if no container is set, all generated metrics will be sent to MAL engine for further processing,
if metrics container is set, all metrics are only stored in the container, and won't be sent to MAL.

@param container the metrics container
oap-server/analyzer/log-analyzer/src/main/java/org/apache/skywalking/oap/log/analyzer/dsl/Binding.java