[#52] object/range: Attach received object header to result

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/services/object/range/res.go

@@ -1,5 +1,15 @@
 package rangesvc
 
+import (
+	"github.com/nspcc-dev/neofs-node/pkg/core/object"
+)
+
+type Result struct {
+	head *object.Object
+
+	stream Streamer
+}
+
 type Response struct {
 	chunk []byte
 }
@@ -7,3 +17,11 @@ type Response struct {
 func (r *Response) PayloadChunk() []byte {
 	return r.chunk
 }
+
+func (r *Result) Head() *object.Object {
+	return r.head
+}
+
+func (r *Result) Stream() Streamer {
+	return r.stream
+}

pkg/services/object/range/service.go

@@ -55,7 +55,7 @@ func NewService(opts ...Option) *Service {
 	}
 }
 
-func (s *Service) GetRange(ctx context.Context, prm *Prm) (Streamer, error) {
+func (s *Service) GetRange(ctx context.Context, prm *Prm) (*Result, error) {
 	headResult, err := s.headSvc.Head(ctx, new(headsvc.Prm).
 		WithAddress(prm.addr).
 		OnlyLocal(prm.local),
@@ -83,12 +83,15 @@ func (s *Service) GetRange(ctx context.Context, prm *Prm) (Streamer, error) {
 		return nil, errors.Wrapf(err, "(%T) could not fill range traverser", s)
 	}
 
-	return &streamer{
-		cfg:            s.cfg,
-		once:           new(sync.Once),
-		ctx:            ctx,
-		prm:            prm,
-		rangeTraverser: rngTraverser,
+	return &Result{
+		head: origin,
+		stream: &streamer{
+			cfg:            s.cfg,
+			once:           new(sync.Once),
+			ctx:            ctx,
+			prm:            prm,
+			rangeTraverser: rngTraverser,
+		},
 	}, nil
 }
 

pkg/services/object/range/v2/service.go

@@ -35,12 +35,12 @@ func NewService(opts ...Option) *Service {
 
 // GetRange calls internal service and returns v2 object payload range stream.
 func (s *Service) GetRange(ctx context.Context, req *objectV2.GetRangeRequest) (objectV2.GetRangeObjectStreamer, error) {
-	stream, err := s.svc.GetRange(ctx, toPrm(req))
+	r, err := s.svc.GetRange(ctx, toPrm(req))
 	if err != nil {
 		return nil, errors.Wrapf(err, "(%T) could not get object payload range data", s)
 	}
 
-	return fromResponse(stream), nil
+	return fromResponse(r.Stream()), nil
 }
 
 func WithInternalService(v *rangesvc.Service) Option {