fixes

Signed-off-by: Won Jun Jang <wjang@uber.com>

Author: black-adder

model/converter/json/from_domain.go

@@ -97,28 +97,28 @@ func (fd fromDomain) convertReferences(span *model.Span, preserveParentID bool)
 		length++
 	}
 	out := make([]json.Reference, 0, length)
-	var parentRef json.Reference
-	if span.ParentSpanID != 0 && !preserveParentID {
-		// TODO this (wrongly) assumes that the reference type is always ChildOf
-		parentRef = json.Reference{
-			RefType: json.ChildOf,
-			TraceID: json.TraceID(span.TraceID.String()),
-			SpanID:  json.SpanID(span.ParentSpanID.String()),
-		}
-		out = append(out, parentRef)
-	}
+	var parentRefAdded bool
 	for _, ref := range span.References {
-		// TODO if the parentRef was wrongly added as a ChildOf ref above, this could
-		// potentially add a FollowsFrom ref and still keep the ChildOf ref
 		newRef := json.Reference{
 			RefType: fd.convertRefType(ref.RefType),
 			TraceID: json.TraceID(ref.TraceID.String()),
 			SpanID:  json.SpanID(ref.SpanID.String()),
 		}
-		if newRef != parentRef {
-			out = append(out, newRef)
+		out = append(out, newRef)
+		if newRef.TraceID == json.TraceID(span.TraceID.String()) &&
+			newRef.SpanID == json.SpanID(span.ParentSpanID.String()) {
+			// Check if the parent reference already exists
+			parentRefAdded = true
 		}
 	}
+	if span.ParentSpanID != 0 && !preserveParentID && !parentRefAdded {
+		// TODO this (wrongly) assumes that the reference type is always ChildOf
+		out = append(out, json.Reference{
+			RefType: json.ChildOf,
+			TraceID: json.TraceID(span.TraceID.String()),
+			SpanID:  json.SpanID(span.ParentSpanID.String()),
+		})
+	}
 	return out
 }