[#349] object: Make patcher apply patching for split header

* Change `PatchApplier` interface: `ApplyAttributesPatch` -> `ApplyHeaderPatch`.
  Make `ApplyHeaderPatch` receive `ApplyHeaderPatchPrm` as parameter;
* Fix `patcher`: apply patch for split header;
* Fix `patcher` unit-tests. Add test-case for split header;
* Extend `Patch` struct with `NewSplitHeader`;
* Change `ObjectPatcher` interface for client: `PatchAttributes` -> `PatchHeader`.
  Fix `objectPatcher`.
* Fix object transformer: since object header sets `SplitHeader` if it's passed.

Signed-off-by: Airat Arifullin <a.arifullin@yadro.com>

client/object_patch.go

@@ -26,11 +26,19 @@ import (
 // usage is unsafe.
 type ObjectPatcher interface {
 	// PatchAttributes patches attributes. Attributes can be patched no more than once,
-	// otherwise, the server returns an error.
+	// otherwise, the server returns an error. `PatchAttributes` and `PatchHeader` are mutually
+	// exclusive - only one method can be used.
 	//
 	// Result means success. Failure reason can be received via Close.
 	PatchAttributes(ctx context.Context, newAttrs []object.Attribute, replace bool) bool
 
+	// PatchHeader patches object's header. Header can be patched no more than once,
+	// otherwise, the server returns an error. `PatchAttributes` and `PatchHeader` are mutually
+	// exclusive - only one method can be used.
+	//
+	// Result means success. Failure reason can be received via Close.
+	PatchHeader(ctx context.Context, prm PatchHeaderPrm) bool
+
 	// PatchPayload patches the object's payload.
 	//
 	// PatchPayload receives `payloadReader` and thus the payload of the patch is read and sent by chunks of
@@ -60,6 +68,14 @@ type ObjectPatcher interface {
 	Close(_ context.Context) (*ResObjectPatch, error)
 }
 
+type PatchHeaderPrm struct {
+	NewSplitHeader *object.SplitHeader
+
+	NewAttributes []object.Attribute
+
+	ReplaceAttributes bool
+}
+
 // ResObjectPatch groups resulting values of ObjectPatch operation.
 type ResObjectPatch struct {
 	statusRes
@@ -163,6 +179,15 @@ func (x *objectPatcher) PatchAttributes(_ context.Context, newAttrs []object.Att
 	})
 }
 
+func (x *objectPatcher) PatchHeader(_ context.Context, prm PatchHeaderPrm) bool {
+	return x.patch(&object.Patch{
+		Address:           x.addr,
+		NewAttributes:     prm.NewAttributes,
+		ReplaceAttributes: prm.ReplaceAttributes,
+		NewSplitHeader:    prm.NewSplitHeader,
+	})
+}
+
 func (x *objectPatcher) PatchPayload(_ context.Context, rng *object.Range, payloadReader io.Reader) bool {
 	offset := rng.GetOffset()
 

client/object_patch_test.go

@@ -177,7 +177,7 @@ func TestObjectPatcher(t *testing.T) {
 				maxChunkLen: test.maxChunkLen,
 			}
 
-			success := patcher.PatchAttributes(context.Background(), nil, false)
+			success := patcher.PatchHeader(context.Background(), PatchHeaderPrm{})
 			require.True(t, success)
 
 			success = patcher.PatchPayload(context.Background(), test.rng, bytes.NewReader([]byte(test.patchPayload)))

object/patch.go

@@ -18,6 +18,10 @@ type Patch struct {
 	// filled with NewAttributes. Otherwise, the attributes are just merged.
 	ReplaceAttributes bool
 
+	// A new split header which is set to object's header. If `nil`, then split header patching
+	// is ignored.
+	NewSplitHeader *SplitHeader
+
 	// Payload patch. If this field is not set, then it assumed such Patch patches only
 	// header (see NewAttributes, ReplaceAttributes).
 	PayloadPatch *PayloadPatch
@@ -41,6 +45,8 @@ func (p *Patch) ToV2() *v2object.PatchRequestBody {
 	v2.SetNewAttributes(attrs)
 	v2.SetReplaceAttributes(p.ReplaceAttributes)
 
+	v2.SetNewSplitHeader(p.NewSplitHeader.ToV2())
+
 	v2.SetPatch(p.PayloadPatch.ToV2())
 
 	return v2
@@ -63,6 +69,8 @@ func (p *Patch) FromV2(patch *v2object.PatchRequestBody) {
 
 	p.ReplaceAttributes = patch.GetReplaceAttributes()
 
+	p.NewSplitHeader = NewSplitHeaderFromV2(patch.GetNewSplitHeader())
+
 	if v2patch := patch.GetPatch(); v2patch != nil {
 		p.PayloadPatch = new(PayloadPatch)
 		p.PayloadPatch.FromV2(v2patch)

object/patcher/patcher.go

@@ -11,10 +11,12 @@ import (
 )
 
 var (
-	ErrOffsetExceedsSize       = errors.New("patch offset exceeds object size")
+	ErrOffsetExceedsSize                       = errors.New("patch offset exceeds object size")
-	ErrInvalidPatchOffsetOrder = errors.New("invalid patch offset order")
+	ErrInvalidPatchOffsetOrder                 = errors.New("invalid patch offset order")
-	ErrPayloadPatchIsNil       = errors.New("nil payload patch")
+	ErrPayloadPatchIsNil                       = errors.New("nil payload patch")
-	ErrAttrPatchAlreadyApplied = errors.New("attribute patch already applied")
+	ErrAttrPatchAlreadyApplied                 = errors.New("attribute patch already applied")
+	ErrHeaderPatchAlreadyApplied               = errors.New("header patch already applied")
+	ErrSplitHeaderPatchAppliedWithPayloadPatch = errors.New("split header patch applied with payload patch")
 )
 
 // PatchRes is the result of patch application.
@@ -27,13 +29,24 @@ type PatchApplier interface {
 	// ApplyAttributesPatch applies the patch only for the object's attributes.
 	//
 	// ApplyAttributesPatch can't be invoked few times, otherwise it returns `ErrAttrPatchAlreadyApplied` error.
+	// `ApplyHeaderPatch` and `ApplyAttributesPatch` are mutually exclusive - only one method can be used.
 	//
 	// The call is idempotent for the original header if it's invoked with empty `newAttrs` and
 	// `replaceAttrs = false`.
 	ApplyAttributesPatch(ctx context.Context, newAttrs []objectSDK.Attribute, replaceAttrs bool) error
 
+	// ApplyHeaderPatch applies the patch only for the object's attributes.
+	//
+	// ApplyHeaderPatch can't be invoked few times, otherwise it returns `ErrHeaderPatchAlreadyApplied` error.
+	// `ApplyHeaderPatch` and `ApplyAttributesPatch` are mutually exclusive - only one method can be used.
+	//
+	// The call is idempotent for the original header if it's invoked with `ApplyHeaderPatchPrm` with not set fields.
+	ApplyHeaderPatch(ctx context.Context, prm ApplyHeaderPatchPrm) error
+
 	// ApplyPayloadPatch applies the patch for the object's payload.
 	//
+	// ApplyPayloadPatch returns `ErrSplitHeaderPatchAppliedWithPayloadPatch` when attempting to apply it with a split header patch.
+	//
 	// ApplyPayloadPatch returns `ErrPayloadPatchIsNil` error if patch is nil.
 	ApplyPayloadPatch(ctx context.Context, payloadPatch *objectSDK.PayloadPatch) error
 
@@ -41,6 +54,14 @@ type PatchApplier interface {
 	Close(context.Context) (PatchRes, error)
 }
 
+type ApplyHeaderPatchPrm struct {
+	NewSplitHeader *objectSDK.SplitHeader
+
+	NewAttributes []objectSDK.Attribute
+
+	ReplaceAttributes bool
+}
+
 // RangeProvider is the interface that provides a method to get original object payload
 // by a given range.
 type RangeProvider interface {
@@ -61,7 +82,9 @@ type patcher struct {
 
 	hdr *objectSDK.Object
 
-	attrPatchAlreadyApplied bool
+	hdrPatchAlreadyApplied bool
+
+	splitHeaderPatchAlreadyApplied bool
 
 	readerBuffSize int
 }
@@ -107,10 +130,10 @@ func New(prm Params) PatchApplier {
 
 func (p *patcher) ApplyAttributesPatch(ctx context.Context, newAttrs []objectSDK.Attribute, replaceAttrs bool) error {
 	defer func() {
-		p.attrPatchAlreadyApplied = true
+		p.hdrPatchAlreadyApplied = true
 	}()
 
-	if p.attrPatchAlreadyApplied {
+	if p.hdrPatchAlreadyApplied {
 		return ErrAttrPatchAlreadyApplied
 	}
 
@@ -127,7 +150,38 @@ func (p *patcher) ApplyAttributesPatch(ctx context.Context, newAttrs []objectSDK
 	return nil
 }
 
+func (p *patcher) ApplyHeaderPatch(ctx context.Context, prm ApplyHeaderPatchPrm) error {
+	defer func() {
+		p.hdrPatchAlreadyApplied = true
+	}()
+
+	if p.hdrPatchAlreadyApplied {
+		return ErrHeaderPatchAlreadyApplied
+	}
+
+	if prm.NewSplitHeader != nil {
+		p.hdr.SetSplitHeader(prm.NewSplitHeader)
+
+		p.splitHeaderPatchAlreadyApplied = true
+	}
+
+	if prm.ReplaceAttributes {
+		p.hdr.SetAttributes(prm.NewAttributes...)
+	} else if len(prm.NewAttributes) > 0 {
+		mergedAttrs := mergeAttributes(prm.NewAttributes, p.hdr.Attributes())
+		p.hdr.SetAttributes(mergedAttrs...)
+	}
+
+	if err := p.objectWriter.WriteHeader(ctx, p.hdr); err != nil {
+		return fmt.Errorf("writer header: %w", err)
+	}
+	return nil
+}
+
 func (p *patcher) ApplyPayloadPatch(ctx context.Context, payloadPatch *objectSDK.PayloadPatch) error {
+	if p.splitHeaderPatchAlreadyApplied {
+		return ErrSplitHeaderPatchAppliedWithPayloadPatch
+	}
 	if payloadPatch == nil {
 		return ErrPayloadPatchIsNil
 	}

object/patcher/patcher_test.go

@@ -106,7 +106,11 @@ func TestPatchRevert(t *testing.T) {
 
 	patcher := New(prm)
 
-	err := patcher.ApplyAttributesPatch(context.Background(), modifPatch.NewAttributes, modifPatch.ReplaceAttributes)
+	err := patcher.ApplyHeaderPatch(context.Background(), ApplyHeaderPatchPrm{
+		NewSplitHeader:    modifPatch.NewSplitHeader,
+		NewAttributes:     modifPatch.NewAttributes,
+		ReplaceAttributes: modifPatch.ReplaceAttributes,
+	})
 	require.NoError(t, err)
 
 	err = patcher.ApplyPayloadPatch(context.Background(), modifPatch.PayloadPatch)
@@ -145,7 +149,11 @@ func TestPatchRevert(t *testing.T) {
 
 	patcher = New(prm)
 
-	err = patcher.ApplyAttributesPatch(context.Background(), revertPatch.NewAttributes, revertPatch.ReplaceAttributes)
+	err = patcher.ApplyHeaderPatch(context.Background(), ApplyHeaderPatchPrm{
+		NewSplitHeader:    revertPatch.NewSplitHeader,
+		NewAttributes:     revertPatch.NewAttributes,
+		ReplaceAttributes: revertPatch.ReplaceAttributes,
+	})
 	require.NoError(t, err)
 
 	err = patcher.ApplyPayloadPatch(context.Background(), revertPatch.PayloadPatch)
@@ -157,7 +165,7 @@ func TestPatchRevert(t *testing.T) {
 	require.Equal(t, originalObjectPayload, patchedPatchedObj.Payload())
 }
 
-func TestPatchRepeatAttributePatch(t *testing.T) {
+func TestPatchRepeatHeaderPatch(t *testing.T) {
 	obj, _ := newTestObject()
 
 	modifPatch := &objectSDK.Patch{}
@@ -187,11 +195,142 @@ func TestPatchRepeatAttributePatch(t *testing.T) {
 
 	patcher := New(prm)
 
-	err := patcher.ApplyAttributesPatch(context.Background(), modifPatch.NewAttributes, modifPatch.ReplaceAttributes)
+	err := patcher.ApplyHeaderPatch(context.Background(), ApplyHeaderPatchPrm{
+		NewSplitHeader:    modifPatch.NewSplitHeader,
+		NewAttributes:     modifPatch.NewAttributes,
+		ReplaceAttributes: modifPatch.ReplaceAttributes,
+	})
 	require.NoError(t, err)
 
-	err = patcher.ApplyAttributesPatch(context.Background(), modifPatch.NewAttributes, modifPatch.ReplaceAttributes)
+	err = patcher.ApplyHeaderPatch(context.Background(), ApplyHeaderPatchPrm{
-	require.ErrorIs(t, err, ErrAttrPatchAlreadyApplied)
+		NewSplitHeader:    modifPatch.NewSplitHeader,
+		NewAttributes:     modifPatch.NewAttributes,
+		ReplaceAttributes: modifPatch.ReplaceAttributes,
+	})
+	require.ErrorIs(t, err, ErrHeaderPatchAlreadyApplied)
+}
+
+func TestPatchSplitHeader(t *testing.T) {
+	obj, _ := newTestObject()
+
+	const (
+		splitIDStr = "a59c9f87-14bc-4a61-95d1-7eb10f036163"
+		parentStr  = "9cRjAaPqUt5zaDAjBkSCqFfPdkE8dHJ7mtRupRjPWp6E"
+		previosStr = "6WaTd9HobT4Z52NnKWHAtjqtQu2Ww5xZwNdT4ptshkKE"
+	)
+
+	splitID := objectSDK.NewSplitID()
+	require.NoError(t, splitID.Parse(splitIDStr))
+
+	var par, prev oid.ID
+	require.NoError(t, par.DecodeString(parentStr))
+	require.NoError(t, prev.DecodeString(previosStr))
+
+	splitHdr := objectSDK.NewSplitHeader()
+	splitHdr.SetSplitID(splitID)
+	splitHdr.SetParentID(par)
+	splitHdr.SetPreviousID(prev)
+
+	originalObjectPayload := []byte("*******************")
+
+	obj.SetPayload(originalObjectPayload)
+	obj.SetPayloadSize(uint64(len(originalObjectPayload)))
+
+	rangeProvider := &mockRangeProvider{
+		originalObjectPayload: originalObjectPayload,
+	}
+
+	t.Run("no payload patch", func(t *testing.T) {
+		patchedObj, _ := newTestObject()
+
+		wr := &mockPatchedObjectWriter{
+			obj: patchedObj,
+		}
+
+		modifPatch := &objectSDK.Patch{
+			NewSplitHeader: splitHdr,
+		}
+
+		prm := Params{
+			Header: obj.CutPayload(),
+
+			RangeProvider: rangeProvider,
+
+			ObjectWriter: wr,
+		}
+
+		patcher := New(prm)
+
+		err := patcher.ApplyHeaderPatch(context.Background(), ApplyHeaderPatchPrm{
+			NewSplitHeader:    modifPatch.NewSplitHeader,
+			NewAttributes:     modifPatch.NewAttributes,
+			ReplaceAttributes: modifPatch.ReplaceAttributes,
+		})
+		require.NoError(t, err)
+
+		splitHdrFromPatchedObj := patchedObj.SplitHeader()
+		require.NotNil(t, splitHdrFromPatchedObj)
+
+		patchObjParID, isSet := splitHdrFromPatchedObj.ParentID()
+		require.True(t, isSet)
+		require.True(t, patchObjParID.Equals(par))
+
+		patchObjPrevID, isSet := splitHdrFromPatchedObj.PreviousID()
+		require.True(t, isSet)
+		require.True(t, patchObjPrevID.Equals(prev))
+
+		require.Equal(t, splitHdrFromPatchedObj.SplitID().String(), splitID.String())
+	})
+
+	t.Run("with payload patch", func(t *testing.T) {
+		patchedObj, _ := newTestObject()
+
+		wr := &mockPatchedObjectWriter{
+			obj: patchedObj,
+		}
+
+		modifPatch := &objectSDK.Patch{
+			NewSplitHeader: splitHdr,
+			PayloadPatch: &objectSDK.PayloadPatch{
+				Range: rangeWithOffestWithLength(10, 0),
+				Chunk: []byte(""),
+			},
+		}
+
+		prm := Params{
+			Header: obj.CutPayload(),
+
+			RangeProvider: rangeProvider,
+
+			ObjectWriter: wr,
+		}
+
+		patcher := New(prm)
+
+		err := patcher.ApplyHeaderPatch(context.Background(), ApplyHeaderPatchPrm{
+			NewSplitHeader:    modifPatch.NewSplitHeader,
+			NewAttributes:     modifPatch.NewAttributes,
+			ReplaceAttributes: modifPatch.ReplaceAttributes,
+		})
+		require.NoError(t, err)
+
+		splitHdrFromPatchedObj := patchedObj.SplitHeader()
+		require.NotNil(t, splitHdrFromPatchedObj)
+
+		patchObjParID, isSet := splitHdrFromPatchedObj.ParentID()
+		require.True(t, isSet)
+		require.True(t, patchObjParID.Equals(par))
+
+		patchObjPrevID, isSet := splitHdrFromPatchedObj.PreviousID()
+		require.True(t, isSet)
+		require.True(t, patchObjPrevID.Equals(prev))
+
+		require.Equal(t, splitHdrFromPatchedObj.SplitID().String(), splitID.String())
+
+		err = patcher.ApplyPayloadPatch(context.Background(), modifPatch.PayloadPatch)
+		require.Error(t, err, ErrSplitHeaderPatchAppliedWithPayloadPatch)
+	})
+
 }
 
 func TestPatchEmptyPayloadPatch(t *testing.T) {
@@ -224,7 +363,11 @@ func TestPatchEmptyPayloadPatch(t *testing.T) {
 
 	patcher := New(prm)
 
-	err := patcher.ApplyAttributesPatch(context.Background(), modifPatch.NewAttributes, modifPatch.ReplaceAttributes)
+	err := patcher.ApplyHeaderPatch(context.Background(), ApplyHeaderPatchPrm{
+		NewSplitHeader:    modifPatch.NewSplitHeader,
+		NewAttributes:     modifPatch.NewAttributes,
+		ReplaceAttributes: modifPatch.ReplaceAttributes,
+	})
 	require.NoError(t, err)
 
 	err = patcher.ApplyPayloadPatch(context.Background(), nil)
@@ -599,7 +742,11 @@ func TestPatch(t *testing.T) {
 
 			for i, patch := range test.patches {
 				if i == 0 {
-					_ = patcher.ApplyAttributesPatch(context.Background(), patch.NewAttributes, patch.ReplaceAttributes)
+					_ = patcher.ApplyHeaderPatch(context.Background(), ApplyHeaderPatchPrm{
+						NewSplitHeader:    patch.NewSplitHeader,
+						NewAttributes:     patch.NewAttributes,
+						ReplaceAttributes: patch.ReplaceAttributes,
+					})
 				}
 
 				if patch.PayloadPatch == nil {

object/transformer/transformer.go

@@ -116,9 +116,14 @@ func fromObject(obj *object.Object) *object.Object {
 	res.SetAttributes(obj.Attributes()...)
 	res.SetType(obj.Type())
 
-	// obj.SetSplitID creates splitHeader but we don't need to do it in case
+	// There are two ways to specify split information:
-	// of small objects, so we should make nil check.
+	// 1. Using explicit SplitHeader. Thus, we only propagate whole split information
-	if obj.SplitID() != nil {
+	//    if it's already set in the source object (use-case: Patch method).
+	// 2. Using SplitID - will automatically generate a SplitHeader, but this is not requiered for
+	//    small objects.
+	if obj.SplitHeader() != nil {
+		res.SetSplitHeader(obj.SplitHeader())
+	} else if obj.SplitID() != nil {
 		res.SetSplitID(obj.SplitID())
 	}