[#1502] shard: Add `IsLocked` method

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>

pkg/local_object_storage/shard/lock.go

@@ -3,6 +3,7 @@ package shard
 import (
 	"fmt"
 
+	meta "github.com/nspcc-dev/neofs-node/pkg/local_object_storage/metabase"
 	cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
 	oid "github.com/nspcc-dev/neofs-sdk-go/object/id"
 )
@@ -28,3 +29,22 @@ func (s *Shard) Lock(idCnr cid.ID, locker oid.ID, locked []oid.ID) error {
 
 	return nil
 }
+
+// IsLocked checks object locking relation of the provided object. Not found object is
+// considered as not locked. Requires healthy metabase, returns ErrDegradedMode otherwise.
+func (s *Shard) IsLocked(addr oid.Address) (bool, error) {
+	m := s.GetMode()
+	if m.NoMetabase() {
+		return false, ErrDegradedMode
+	}
+
+	var prm meta.IsLockedPrm
+	prm.SetAddress(addr)
+
+	res, err := s.metaBase.IsLocked(prm)
+	if err != nil {
+		return false, err
+	}
+
+	return res.Locked(), nil
+}

pkg/local_object_storage/shard/lock_test.go

@@ -16,6 +16,7 @@ import (
 	cidtest "github.com/nspcc-dev/neofs-sdk-go/container/id/test"
 	"github.com/nspcc-dev/neofs-sdk-go/object"
 	oid "github.com/nspcc-dev/neofs-sdk-go/object/id"
+	oidtest "github.com/nspcc-dev/neofs-sdk-go/object/id/test"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/zap"
 )
@@ -138,5 +139,39 @@ func TestShard_Lock(t *testing.T) {
 		_, err = sh.Get(getPrm)
 		require.ErrorAs(t, err, new(apistatus.ObjectNotFound))
 	})
-
+}
+
+func TestShard_IsLocked(t *testing.T) {
+	sh := newShard(t, false)
+
+	cnr := cidtest.ID()
+	obj := generateObjectWithCID(t, cnr)
+	cnrID, _ := obj.ContainerID()
+	objID, _ := obj.ID()
+
+	lockID := oidtest.ID()
+
+	// put the object
+
+	var putPrm shard.PutPrm
+	putPrm.SetObject(obj)
+
+	_, err := sh.Put(putPrm)
+	require.NoError(t, err)
+
+	// not locked object is not locked
+
+	locked, err := sh.IsLocked(objectcore.AddressOf(obj))
+	require.NoError(t, err)
+
+	require.False(t, locked)
+
+	// locked object is locked
+
+	require.NoError(t, sh.Lock(cnrID, lockID, []oid.ID{objID}))
+
+	locked, err = sh.IsLocked(objectcore.AddressOf(obj))
+	require.NoError(t, err)
+
+	require.True(t, locked)
 }