[receiver/skywalking]: fix parentSpanId lost when crossing segments

receiver/skywalkingreceiver/skywalkingproto_to_traces.go

@@ -117,9 +117,15 @@ func swSpanToSpan(traceID string, segmentID string, span *agentV3.SpanObject, de
  // so use segmentId to convert to an unique otel-span
  dest.SetSpanID(segmentIDToSpanID(segmentID, uint32(span.GetSpanId())))
 
- // parent spanid = -1, means(root span) no parent span in skywalking,so just make otlp's parent span id empty.
+ // parent spanid = -1, means(root span) no parent span in current skywalking segment, so it is necessary to search for the parent segment.
  if span.ParentSpanId != -1 {
  dest.SetParentSpanID(segmentIDToSpanID(segmentID, uint32(span.GetParentSpanId())))
+ } else {
+ // TODO: SegmentReference references usually have only one element, but in batch consumer case, such as in MQ or async batch process, it could be multiple.
+ // We only handle one element for now.
+ if len(span.Refs) == 1 {
+ dest.SetParentSpanID(segmentIDToSpanID(span.Refs[0].GetParentTraceSegmentId(), uint32(span.Refs[0].GetParentSpanId())))
+ }
  }
 
  dest.SetName(span.OperationName)

receiver/skywalkingreceiver/skywalkingproto_to_traces_test.go

@@ -309,6 +309,41 @@ func Test_segmentIdToSpanId_Unique(t *testing.T) {
  assert.NotEqual(t, results[0], results[1])
 }
 
+func Test_swSpanToSpan_ParentSpanId(t *testing.T) {
+ type args struct {
+ span *agentV3.SpanObject
+ }
+ tests := []struct {
+ name string
+ args args
+ want pcommon.SpanID
+ }{
+ {
+ name: "mock-sw-span-with-parent-segment",
+ args: args{span: &agentV3.SpanObject{
+ ParentSpanId: -1,
+ Refs: []*agentV3.SegmentReference{{
+ ParentTraceSegmentId: "4f2f27748b8e44ecaf18fe0347194e86.33.16560607369950066",
+ ParentSpanId: 123,
+ }}}},
+ want: [8]byte{233, 196, 85, 168, 37, 66, 48, 106},
+ },
+ {
+ name: "mock-sw-span-without-parent-segment",
+ args: args{span: &agentV3.SpanObject{Refs: []*agentV3.SegmentReference{{
+ ParentSpanId: -1,
+ }}}},
+ },
+ }
+ for _, tt := range tests {
+ t.Run(tt.name, func(t *testing.T) {
+ dest := ptrace.NewSpan()
+ swSpanToSpan("de5980b8-fce3-4a37-aab9-b4ac3af7eedd", "", tt.args.span, dest)
+ assert.Equal(t, tt.want, dest.ParentSpanID())
+ })
+ }
+}
+
 func generateTracesOneEmptyResourceSpans() ptrace.Span {
  td := ptrace.NewTraces()
  resourceSpan := td.ResourceSpans().AppendEmpty()