[#789] shard: Add option to refill metabase on initialization

Add `WithRefillMetabase` option constructor which allows to set flag to
refill metabase.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/local_object_storage/shard/control.go

@@ -32,16 +32,24 @@ func (s *Shard) Open() error {
 
 // Init initializes all Shard's components.
 func (s *Shard) Init() error {
-	components := []interface{ Init() error }{
-		s.blobStor, s.metaBase,
+	var fMetabase func() error
+
+	if s.needRefillMetabase() {
+		fMetabase = s.refillMetabase
+	} else {
+		fMetabase = s.metaBase.Init
+	}
+
+	components := []func() error{
+		s.blobStor.Init, fMetabase,
 	}
 
 	if s.hasWriteCache() {
-		components = append(components, s.writeCache)
+		components = append(components, s.writeCache.Init)
 	}
 
 	for _, component := range components {
-		if err := component.Init(); err != nil {
+		if err := component(); err != nil {
 			return fmt.Errorf("could not initialize %T: %w", component, err)
 		}
 	}

pkg/local_object_storage/shard/shard.go

@@ -36,6 +36,8 @@ type Option func(*cfg)
 type ExpiredObjectsCallback func(context.Context, []*object.Address)
 
 type cfg struct {
+	refillMetabase bool
+
 	rmBatchSize int
 
 	useWriteCache bool
@@ -139,6 +141,11 @@ func (s Shard) hasWriteCache() bool {
 	return s.cfg.useWriteCache
 }
 
+// needRefillMetabase returns true if metabase is needed to be refilled.
+func (s Shard) needRefillMetabase() bool {
+	return s.cfg.refillMetabase
+}
+
 // WithRemoverBatchSize returns option to set batch size
 // of single removal operation.
 func WithRemoverBatchSize(sz int) Option {
@@ -178,3 +185,10 @@ func WithExpiredObjectsCallback(cb ExpiredObjectsCallback) Option {
 		c.expiredTombstonesCallback = cb
 	}
 }
+
+// WithRefillMetabase returns option to set flag to refill the Metabase on Shard's initialization step.
+func WithRefillMetabase(v bool) Option {
+	return func(c *cfg) {
+		c.refillMetabase = v
+	}
+}