[#50] services/object: Implement GetRange service

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

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

@@ -0,0 +1,25 @@
+package rangesvc
+
+import (
+	"github.com/nspcc-dev/neofs-api-go/pkg/object"
+	objectV2 "github.com/nspcc-dev/neofs-api-go/v2/object"
+	rangesvc "github.com/nspcc-dev/neofs-node/pkg/services/object/range"
+)
+
+func toPrm(req *objectV2.GetRangeRequest) *rangesvc.Prm {
+	body := req.GetBody()
+
+	return new(rangesvc.Prm).
+		WithAddress(
+			object.NewAddressFromV2(body.GetAddress()),
+		).
+		WithRange(object.NewRangeFromV2(body.GetRange())).
+		OnlyLocal(req.GetMetaHeader().GetTTL() == 1) // FIXME: use constant
+}
+
+func fromResponse(stream rangesvc.Streamer) objectV2.GetRangeObjectStreamer {
+	return &streamer{
+		stream: stream,
+		body:   new(objectV2.GetRangeResponseBody),
+	}
+}