[#238] shard: Support raw flag in Head method

Signed-off-by: Alex Vanin <alexey@nspcc.ru>

pkg/local_object_storage/shard/head.go

@@ -9,6 +9,7 @@ import (
 // HeadPrm groups the parameters of Head operation.
 type HeadPrm struct {
 	addr *objectSDK.Address
+	raw  bool
 }
 
 // HeadRes groups resulting values of Head operation.
@@ -27,6 +28,17 @@ func (p *HeadPrm) WithAddress(addr *objectSDK.Address) *HeadPrm {
 	return p
 }
 
+// WithRaw is a Head option to set raw flag value. If flag is unset, then Head
+// returns header of virtual object, otherwise it returns SplitInfo of virtual
+// object.
+func (p *HeadPrm) WithRaw(raw bool) *HeadPrm {
+	if p != nil {
+		p.raw = raw
+	}
+
+	return p
+}
+
 // Object returns the requested object header.
 func (r *HeadRes) Object() *object.Object {
 	return r.obj
@@ -36,9 +48,13 @@ func (r *HeadRes) Object() *object.Object {
 //
 // Returns any error encountered.
 func (s *Shard) Head(prm *HeadPrm) (*HeadRes, error) {
-	head, err := meta.Get(s.metaBase, prm.addr)
+	headParams := new(meta.GetPrm).
+		WithAddress(prm.addr).
+		WithRaw(prm.raw)
+
+	head, err := s.metaBase.Get(headParams)
 
 	return &HeadRes{
-		obj: head,
+		obj: head.Header(),
 	}, err
 }

pkg/local_object_storage/shard/head_test.go

@@ -1,8 +1,10 @@
 package shard_test
 
 import (
+	"errors"
 	"testing"
 
+	objectSDK "github.com/nspcc-dev/neofs-api-go/pkg/object"
 	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/shard"
 	"github.com/stretchr/testify/require"
 )
@@ -26,19 +28,55 @@ func TestShard_Head(t *testing.T) {
 }
 
 func testShardHead(t *testing.T, sh *shard.Shard) {
+	putPrm := new(shard.PutPrm)
+	headPrm := new(shard.HeadPrm)
+
+	t.Run("regular object", func(t *testing.T) {
 		obj := generateRawObject(t)
 		addAttribute(obj, "foo", "bar")
 
-	putPrm := new(shard.PutPrm)
 		putPrm.WithObject(obj.Object())
 
 		_, err := sh.Put(putPrm)
 		require.NoError(t, err)
 
-	headPrm := new(shard.HeadPrm)
 		headPrm.WithAddress(obj.Object().Address())
 
 		res, err := sh.Head(headPrm)
 		require.NoError(t, err)
 		require.Equal(t, obj.Object(), res.Object())
+	})
+
+	t.Run("virtual object", func(t *testing.T) {
+		cid := generateCID()
+		splitID := objectSDK.NewSplitID()
+
+		parent := generateRawObjectWithCID(t, cid)
+		addAttribute(parent, "foo", "bar")
+
+		child := generateRawObjectWithCID(t, cid)
+		child.SetParent(parent.Object().SDK())
+		child.SetParentID(parent.ID())
+		child.SetSplitID(splitID)
+
+		putPrm.WithObject(child.Object())
+
+		_, err := sh.Put(putPrm)
+		require.NoError(t, err)
+
+		headPrm.WithAddress(parent.Object().Address())
+		headPrm.WithRaw(true)
+
+		var siErr *objectSDK.SplitInfoError
+
+		_, err = sh.Head(headPrm)
+		require.True(t, errors.As(err, &siErr))
+
+		headPrm.WithAddress(parent.Object().Address())
+		headPrm.WithRaw(false)
+
+		head, err := sh.Head(headPrm)
+		require.NoError(t, err)
+		require.Equal(t, parent.Object(), head.Object())
+	})
 }