code: def StreamMetrics(self, request_iterator, context):
          LOG.debug("StreamMetrics called")
          collect_args = (next(request_iterator))
          max_metrics_buffer = 0
          max_collect_duration = 0
          cfg = Metric(pb=collect_args.Metrics_Arg.metrics[0])
          try:
              max_metrics_buffer = int(cfg.config["max-metrics-buffer"])
          except Exception as ex:
              LOG.debug("Unable to get schedule parameters: {}".format(ex))
          try:
              max_collect_duration = int(cfg.config["max-collect-duration"])
          except Exception as ex:
              LOG.debug("Unable to get schedule parameters: {}".format(ex))
          if max_metrics_buffer > 0:
              self.max_metrics_buffer = max_metrics_buffer
          if max_collect_duration > 0:
              self.max_collect_duration = max_collect_duration
          thread = threading.Thread(target=self._stream_wrapper, args=(collect_args,),)
          thread.daemon = True
          thread.start()
          metrics = []
          metrics_to_stream = []
          stream_timeout = self.max_collect_duration
          while context.is_active():
              try:
                  t_start = time.time()
                  metrics = self.metrics_queue.get(block=True, timeout=stream_timeout)
                  elapsed = round(time.time() - t_start)
                  stream_timeout -= elapsed
              except queue.Empty:
                  LOG.debug("Max collect duration exceeded. Streaming {} metrics".format(len(metrics_to_stream)))
                  metrics_col = CollectReply(Metrics_Reply=MetricsReply(metrics=[m.pb for m in metrics_to_stream]))
                  metrics_to_stream = []
                  stream_timeout = self.max_collect_duration
                  yield metrics_col
              else:
                  for metric in metrics:
                      metrics_to_stream.append(metric)
                      if len(metrics_to_stream) == self.max_metrics_buffer:
                          LOG.debug("Max metrics buffer reached. Streaming {} metrics".format(len(metrics_to_stream)))
                          metrics_col = CollectReply(
                              Metrics_Reply=MetricsReply(metrics=[m.pb for m in metrics_to_stream]))
                          metrics_to_stream = []
                          stream_timeout = self.max_collect_duration
                          yield metrics_col
                  if self.max_metrics_buffer == 0:
                      LOG.debug("Max metrics buffer set to 0. Streaming {} metrics".format(len(metrics_to_stream)))
                      metrics_col = CollectReply(Metrics_Reply=MetricsReply(metrics=[m.pb for m in metrics_to_stream]))
                      metrics_to_stream = []
                      stream_timeout = self.max_collect_duration
                      yield metrics_col
          self.done_queue.put(True)