Merge pull request #29 from zalando/fix_empty_grpc_response_in_pb

Fix empty grpc response in lightstep_pb + set span.custom_kind only when span kind is unspecified

Author: silentz

internal/lightstep_pb/grpc/server.go

@@ -3,9 +3,11 @@ package grpc
 import (
 	"context"
 	"errors"
+	"net"
+	"sync"
+
 	"go.opentelemetry.io/collector/component/componentstatus"
 	"go.opentelemetry.io/collector/config/configgrpc"
-	"sync"
 
 	lightstepCommon "github.com/zalando/otelcol-lightstep-receiver/internal/lightstep_common"
 	"github.com/zalando/otelcol-lightstep-receiver/internal/lightstep_pb"
@@ -19,7 +21,6 @@ import (
 	"go.opentelemetry.io/collector/receiver/receiverhelper"
 	"go.uber.org/zap"
 	"google.golang.org/grpc"
-	"net"
 )
 
 const transport = "pbgrpc"
@@ -99,7 +100,9 @@ func (s *ServerGRPC) Report(ctx context.Context, rq *pb.ReportRequest) (*pb.Repo
 	lr := lightstep_pb.NewLightstepRequest(rq, s.telemetry, transport)
 	if projectTraces, err = lr.ToOtel(ctx); err != nil {
 		s.telemetry.IncrementFailed(transport, 1)
-		return nil, err
+		return &pb.ReportResponse{
+			Errors: []string{err.Error()},
+		}, err
 	}
 	s.telemetry.IncrementProcessed(transport, 1)
 	s.telemetry.IncrementClientDropSpans(projectTraces.ServiceName, projectTraces.ClientSpansDropped)
@@ -113,5 +116,13 @@ func (s *ServerGRPC) Report(ctx context.Context, rq *pb.ReportRequest) (*pb.Repo
 	err = s.nextTraces.ConsumeTraces(ctx, projectTraces.Traces)
 	s.obsreport.EndTracesOp(ctx, "protobuf-grpc", spanCount, err)
 
-	return nil, err
+	if err != nil {
+		return &pb.ReportResponse{
+			Errors: []string{err.Error()},
+		}, err
+	}
+
+	return &pb.ReportResponse{
+		Errors: nil,
+	}, nil
 }

internal/lightstep_pb/transform_test.go

@@ -94,7 +94,7 @@ func TestTransformation(t *testing.T) {
 						},
 						{
 							Key:   "span.kind",
-							Value: &pb.KeyValue_StringValue{StringValue: []byte("client")},
+							Value: &pb.KeyValue_StringValue{StringValue: []byte("special_span_kind")},
 						},
 					},
 					Logs: []*pb.Log{
@@ -134,7 +134,7 @@ func TestTransformation(t *testing.T) {
 	is.Equal(span.ParentSpanID().String(), "24be8e394663fb1e")
 	is.Equal(span.StartTimestamp().AsTime().UnixNano(), int64(1718207928350615000))
 	is.Equal(span.EndTimestamp().AsTime().UnixNano(), int64(1718207928350715000))
-	is.Equal(span.Kind(), ptrace.SpanKindClient)
+	is.Equal(span.Kind(), ptrace.SpanKindUnspecified)
 
 	var (
 		ok bool
@@ -163,7 +163,7 @@ func TestTransformation(t *testing.T) {
 
 	v, ok = span.Attributes().Get("span.custom_kind")
 	is.True(ok)
-	is.Equal(v.Str(), "client")
+	is.Equal(v.Str(), "special_span_kind")
 
 	is.Equal(span.Events().Len(), 1)
 	is.Equal(span.Events().At(0).Name(), "event-name")

internal/lightstep_thrift/transform.go

@@ -103,8 +103,10 @@ func (tr *Request) ToOtel(ctx context.Context) (*lightstepCommon.ProjectTraces,
 
 		if spanKind, ok := attr.Get("span.kind"); ok {
 			otelSpanKind, stringSpanKind := lightstepCommon.ParseSpanKindAttributeValue(spanKind)
-			attr.PutStr("span.custom_kind", stringSpanKind)
 			s.SetKind(otelSpanKind)
+			if otelSpanKind == ptrace.SpanKindUnspecified {
+				attr.PutStr("span.custom_kind", stringSpanKind)
+			}
 		}
 
 		for _, log := range span.LogRecords {