public void CheckForceFlushExport(int timeout)
        {
            using var exporter  = new TestActivityExporter();
            using var processor = new BatchExportActivityProcessor(
                      exporter,
                      maxQueueSize: 3,
                      maxExportBatchSize: 3,
                      exporterTimeoutMilliseconds: 30000);

            processor.OnEnd(new Activity("start1"));
            processor.OnEnd(new Activity("start2"));

            Assert.Equal(0, processor.ProcessedCount);

            // waiting to see if time is triggering the exporter
            Thread.Sleep(1_000);
            Assert.Empty(exporter.Exported);

            // forcing flush
            processor.ForceFlush(timeout);

            if (timeout == 0)
            {
                // ForceFlush(0) will trigger flush and return immediately, so let's sleep for a while
                Thread.Sleep(1_000);
            }

            Assert.Equal(2, exporter.Exported.Count);

            Assert.Equal(2, processor.ProcessedCount);
            Assert.Equal(2, processor.ReceivedCount);
            Assert.Equal(0, processor.DroppedCount);
        }
        public void CheckShutdownExport(int timeout)
        {
            using var exporter  = new TestActivityExporter();
            using var processor = new BatchExportActivityProcessor(
                      exporter,
                      maxQueueSize: 3,
                      maxExportBatchSize: 3,
                      exporterTimeoutMilliseconds: 30000);

            processor.OnEnd(new Activity("start"));
            processor.Shutdown(timeout);

            if (timeout == 0)
            {
                // ForceFlush(0) will trigger flush and return immediately, so let's sleep for a while
                Thread.Sleep(1_000);
            }

            Assert.Single(exporter.Exported);

            Assert.Equal(1, processor.ProcessedCount);
            Assert.Equal(1, processor.ReceivedCount);
            Assert.Equal(0, processor.DroppedCount);
        }