From c064760f5d1b534f943e43df3c29e24a2b972ad4 Mon Sep 17 00:00:00 2001
From: Leonard Lyubich <leonard@nspcc.ru>
Date: Thu, 10 Dec 2020 11:56:18 +0300
Subject: [PATCH] [#226] sdk/object: Implement Tombstone type with field access
 and encoding

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
---
 pkg/object/tombstone.go      | 118 +++++++++++++++++++++++++++++++++++
 pkg/object/tombstone_test.go |  65 +++++++++++++++++++
 2 files changed, 183 insertions(+)
 create mode 100644 pkg/object/tombstone.go
 create mode 100644 pkg/object/tombstone_test.go

diff --git a/pkg/object/tombstone.go b/pkg/object/tombstone.go
new file mode 100644
index 0000000..85fb569
--- /dev/null
+++ b/pkg/object/tombstone.go
@@ -0,0 +1,118 @@
+package object
+
+import (
+	"github.com/nspcc-dev/neofs-api-go/v2/refs"
+	"github.com/nspcc-dev/neofs-api-go/v2/tombstone"
+)
+
+// Tombstone represents v2-compatible tombstone structure.
+type Tombstone tombstone.Tombstone
+
+// NewTombstoneFromV2 wraps v2 Tombstone message to Tombstone.
+func NewTombstoneFromV2(tV2 *tombstone.Tombstone) *Tombstone {
+	return (*Tombstone)(tV2)
+}
+
+// NewTombstone creates and initializes blank Tombstone.
+func NewTombstone() *Tombstone {
+	return NewTombstoneFromV2(new(tombstone.Tombstone))
+}
+
+// ExpirationEpoch return number of tombstone expiration epoch.
+func (t *Tombstone) ExpirationEpoch() uint64 {
+	return (*tombstone.Tombstone)(t).
+		GetExpirationEpoch()
+}
+
+// SetExpirationEpoch sets number of tombstone expiration epoch.
+func (t *Tombstone) SetExpirationEpoch(v uint64) {
+	(*tombstone.Tombstone)(t).
+		SetExpirationEpoch(v)
+}
+
+// SplitID returns identifier of object split hierarchy.
+func (t *Tombstone) SplitID() *SplitID {
+	return NewSplitIDFromV2(
+		(*tombstone.Tombstone)(t).
+			GetSplitID(),
+	)
+}
+
+// SetSplitID sets identifier of object split hierarchy.
+func (t *Tombstone) SetSplitID(v *SplitID) {
+	(*tombstone.Tombstone)(t).
+		SetSplitID(v.ToV2())
+}
+
+// SplitID returns identifier of object split hierarchy.
+func (t *Tombstone) Members() []*ID {
+	msV2 := (*tombstone.Tombstone)(t).
+		GetMembers()
+
+	if msV2 == nil {
+		return nil
+	}
+
+	ms := make([]*ID, 0, len(msV2))
+
+	for i := range msV2 {
+		ms = append(ms, NewIDFromV2(msV2[i]))
+	}
+
+	return ms
+}
+
+// SplitID returns identifier of object split hierarchy.
+func (t *Tombstone) SetMembers(v []*ID) {
+	var ms []*refs.ObjectID
+
+	if v != nil {
+		ms = (*tombstone.Tombstone)(t).
+			GetMembers()
+
+		if ln := len(v); cap(ms) >= ln {
+			ms = ms[:0]
+		} else {
+			ms = make([]*refs.ObjectID, 0, ln)
+		}
+
+		for i := range v {
+			ms = append(ms, v[i].ToV2())
+		}
+	}
+
+	(*tombstone.Tombstone)(t).
+		SetMembers(ms)
+}
+
+// Marshal marshals Tombstone into a protobuf binary form.
+//
+// Buffer is allocated when the argument is empty.
+// Otherwise, the first buffer is used.
+func (t *Tombstone) Marshal(b ...[]byte) ([]byte, error) {
+	var buf []byte
+	if len(b) > 0 {
+		buf = b[0]
+	}
+
+	return (*tombstone.Tombstone)(t).
+		StableMarshal(buf)
+}
+
+// Unmarshal unmarshals protobuf binary representation of Tombstone.
+func (t *Tombstone) Unmarshal(data []byte) error {
+	return (*tombstone.Tombstone)(t).
+		Unmarshal(data)
+}
+
+// MarshalJSON encodes Tombstone to protobuf JSON format.
+func (t *Tombstone) MarshalJSON() ([]byte, error) {
+	return (*tombstone.Tombstone)(t).
+		MarshalJSON()
+}
+
+// UnmarshalJSON decodes Tombstone from protobuf JSON format.
+func (t *Tombstone) UnmarshalJSON(data []byte) error {
+	return (*tombstone.Tombstone)(t).
+		UnmarshalJSON(data)
+}
diff --git a/pkg/object/tombstone_test.go b/pkg/object/tombstone_test.go
new file mode 100644
index 0000000..21103ba
--- /dev/null
+++ b/pkg/object/tombstone_test.go
@@ -0,0 +1,65 @@
+package object
+
+import (
+	"crypto/rand"
+	"crypto/sha256"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func generateIDList(sz int) []*ID {
+	res := make([]*ID, sz)
+	cs := [sha256.Size]byte{}
+
+	for i := 0; i < sz; i++ {
+		res[i] = NewID()
+		rand.Read(cs[:])
+		res[i].SetSHA256(cs)
+	}
+
+	return res
+}
+
+func TestTombstone(t *testing.T) {
+	ts := NewTombstone()
+
+	exp := uint64(13)
+	ts.SetExpirationEpoch(exp)
+	require.Equal(t, exp, ts.ExpirationEpoch())
+
+	splitID := NewSplitID()
+	ts.SetSplitID(splitID)
+	require.Equal(t, splitID, ts.SplitID())
+
+	members := generateIDList(3)
+	ts.SetMembers(members)
+	require.Equal(t, members, ts.Members())
+}
+
+func TestTombstoneEncoding(t *testing.T) {
+	ts := NewTombstone()
+	ts.SetExpirationEpoch(13)
+	ts.SetSplitID(NewSplitID())
+	ts.SetMembers(generateIDList(5))
+
+	t.Run("binary", func(t *testing.T) {
+		data, err := ts.Marshal()
+		require.NoError(t, err)
+
+		ts2 := NewTombstone()
+		require.NoError(t, ts2.Unmarshal(data))
+
+		require.Equal(t, ts, ts2)
+	})
+
+	t.Run("json", func(t *testing.T) {
+		data, err := ts.MarshalJSON()
+		require.NoError(t, err)
+
+		ts2 := NewTombstone()
+		require.NoError(t, ts2.UnmarshalJSON(data))
+
+		require.Equal(t, ts, ts2)
+	})
+}