feature/exporter: add Drop Counts for oltptracer's event and link

CHANGELOG.md

@@ -13,6 +13,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - Support `OTEL_EXPORTER_ZIPKIN_ENDPOINT` env to specify zipkin collector endpoint (#2490)
 - Log the configuration of TracerProviders, and Tracers for debugging. To enable use a logger with Verbosity (V level) >=1
 - Added environment variables for: `OTEL_BSP_SCHEDULE_DELAY`, `OTEL_BSP_EXPORT_TIMEOUT`, `OTEL_BSP_MAX_QUEUE_SIZE` and `OTEL_BSP_MAX_EXPORT_BATCH_SIZE` (#2515)
+- Add Drop Counts for oltptracer's event and link (#2601)
 
 ### Changed
 

exporters/otlp/otlptrace/internal/tracetransform/span.go

@@ -162,9 +162,10 @@ func links(links []tracesdk.Link) []*tracepb.Span_Link {
 		sid := otLink.SpanContext.SpanID()
 
 		sl = append(sl, &tracepb.Span_Link{
-			TraceId:    tid[:],
-			SpanId:     sid[:],
-			Attributes: KeyValues(otLink.Attributes),
+			TraceId:                tid[:],
+			SpanId:                 sid[:],
+			Attributes:             KeyValues(otLink.Attributes),
+			DroppedAttributesCount: uint32(otLink.DroppedAttributeCount),
 		})
 	}
 	return sl
@@ -191,10 +192,10 @@ func spanEvents(es []tracesdk.Event) []*tracepb.Span_Event {
 		nEvents++
 		events = append(events,
 			&tracepb.Span_Event{
-				Name:         e.Name,
-				TimeUnixNano: uint64(e.Time.UnixNano()),
-				Attributes:   KeyValues(e.Attributes),
-				// TODO (rghetia) : Add Drop Counts when supported.
+				Name:                   e.Name,
+				TimeUnixNano:           uint64(e.Time.UnixNano()),
+				Attributes:             KeyValues(e.Attributes),
+				DroppedAttributesCount: uint32(e.DroppedAttributeCount),
 			},
 		)
 	}