From ec21040542a314217a142dac08050d84469a3147 Mon Sep 17 00:00:00 2001
From: Leonard Lyubich <leonard@nspcc.ru>
Date: Fri, 18 Dec 2020 13:39:44 +0300
Subject: [PATCH] [#264] transformer: Finalize parent header once

In previous implementation parent object header finalized twice in size
limiter + formatter. On the one hand, this added redundant action, on the
other hand, it could provoke a difference in the headers of the linking and
the last part. Change formatter to finalize parent header if it does not
container the signature. Change size limiter to reuse parent header after
last child finalization in linking child.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
---
 .../object_manager/transformer/fmt.go         | 13 +++++++----
 .../object_manager/transformer/transformer.go |  7 +++---
 .../object_manager/transformer/types.go       | 23 +++++++++++++++++++
 3 files changed, 36 insertions(+), 7 deletions(-)

diff --git a/pkg/services/object_manager/transformer/fmt.go b/pkg/services/object_manager/transformer/fmt.go
index c44e9f95e..a470ef057 100644
--- a/pkg/services/object_manager/transformer/fmt.go
+++ b/pkg/services/object_manager/transformer/fmt.go
@@ -69,9 +69,12 @@ func (f *formatter) Close() (*AccessIdentifiers, error) {
 	f.obj.SetSessionToken(f.prm.SessionToken)
 	f.obj.SetCreationEpoch(curEpoch)
 
-	var parID *objectSDK.ID
+	var (
+		parID  *objectSDK.ID
+		parHdr *objectSDK.Object
+	)
 
-	if par := f.obj.Parent(); par != nil {
+	if par := f.obj.Parent(); par != nil && par.Signature() == nil {
 		rawPar := objectSDK.NewRawFromV2(par.ToV2())
 
 		rawPar.SetSessionToken(f.prm.SessionToken)
@@ -82,8 +85,9 @@ func (f *formatter) Close() (*AccessIdentifiers, error) {
 		}
 
 		parID = rawPar.ID()
+		parHdr = rawPar.Object()
 
-		f.obj.SetParent(rawPar.Object())
+		f.obj.SetParent(parHdr)
 	}
 
 	if err := objectSDK.SetIDWithSignature(f.prm.Key, f.obj.SDK()); err != nil {
@@ -100,5 +104,6 @@ func (f *formatter) Close() (*AccessIdentifiers, error) {
 
 	return new(AccessIdentifiers).
 		WithSelfID(f.obj.ID()).
-		WithParentID(parID), nil
+		WithParentID(parID).
+		WithParent(parHdr), nil
 }
diff --git a/pkg/services/object_manager/transformer/transformer.go b/pkg/services/object_manager/transformer/transformer.go
index d2ec5e068..cf036aa82 100644
--- a/pkg/services/object_manager/transformer/transformer.go
+++ b/pkg/services/object_manager/transformer/transformer.go
@@ -196,7 +196,7 @@ func (s *payloadSizeLimiter) release(close bool) (*AccessIdentifiers, error) {
 
 	if withParent {
 		// generate and release linking object
-		s.initializeLinking()
+		s.initializeLinking(ids.Parent())
 		s.initializeCurrent()
 
 		if _, err := s.release(false); err != nil {
@@ -214,9 +214,9 @@ func writeHashes(hashers []*payloadChecksumHasher) {
 	}
 }
 
-func (s *payloadSizeLimiter) initializeLinking() {
+func (s *payloadSizeLimiter) initializeLinking(parHdr *objectSDK.Object) {
 	s.current = fromObject(s.current)
-	s.current.SetParent(s.parent.Object().SDK())
+	s.current.SetParent(parHdr)
 	s.current.SetChildren(s.previous...)
 	s.current.SetSplitID(s.splitID)
 }
@@ -279,6 +279,7 @@ func (s *payloadSizeLimiter) detachParent() {
 	s.parent = s.current
 	s.current = fromObject(s.parent)
 	s.parent.ResetRelations()
+	s.parent.SetSignature(nil)
 	s.parentHashers = s.currentHashers
 
 	// return source attributes
diff --git a/pkg/services/object_manager/transformer/types.go b/pkg/services/object_manager/transformer/types.go
index 14a6d719a..42c537f09 100644
--- a/pkg/services/object_manager/transformer/types.go
+++ b/pkg/services/object_manager/transformer/types.go
@@ -12,6 +12,8 @@ import (
 // Consists of the ID of the stored object and the ID of the parent object.
 type AccessIdentifiers struct {
 	par, self *objectSDK.ID
+
+	parHdr *objectSDK.Object
 }
 
 // ObjectTarget is an interface of the object writer.
@@ -88,3 +90,24 @@ func (a *AccessIdentifiers) WithParentID(v *objectSDK.ID) *AccessIdentifiers {
 
 	return res
 }
+
+// Parent return identifier of the parent of the written object.
+func (a *AccessIdentifiers) Parent() *objectSDK.Object {
+	if a != nil {
+		return a.parHdr
+	}
+
+	return nil
+}
+
+// WithParentID returns AccessIdentifiers with passed parent identifier.
+func (a *AccessIdentifiers) WithParent(v *objectSDK.Object) *AccessIdentifiers {
+	res := a
+	if res == nil {
+		res = new(AccessIdentifiers)
+	}
+
+	res.parHdr = v
+
+	return res
+}