[#918] engine: Move shard to degraded mode if metabase open failed

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

internal/logs/logs.go

@@ -571,4 +571,5 @@ const (
 	GetSvcV2FailedToParseNodeExternalAddresses                              = "failed to parse node external addresses"
 	GetSvcV2FailedToGetRangeHashFromNode                                    = "failed to get range hash from node"
 	GetSvcV2FailedToGetRangeHashFromAllOfContainerNodes                     = "failed to get range hash from all of container nodes"
+	FailedToUpdateShardID                                                   = "failed to update shard id"
 )

pkg/local_object_storage/engine/control_test.go

@@ -118,7 +118,7 @@ func TestInitializationFailure(t *testing.T) {
 	})
 }
 
-func testEngineFailInitAndReload(t *testing.T, errOnAdd bool, opts []shard.Option, beforeReload func()) {
+func testEngineFailInitAndReload(t *testing.T, degradedMode bool, opts []shard.Option, beforeReload func()) {
 	var configID string
 
 	e := New()
@@ -126,33 +126,30 @@ func testEngineFailInitAndReload(t *testing.T, errOnAdd bool, opts []shard.Optio
 		require.NoError(t, e.Close(context.Background()))
 	}()
 	_, err := e.AddShard(context.Background(), opts...)
-	if errOnAdd {
-		require.Error(t, err)
-		// This branch is only taken when we cannot update shard ID in the metabase.
-		// The id cannot be encountered during normal operation, but it is ok for tests:
-		// it is only compared for equality with other ids and we have 0 shards here.
-		configID = "id"
-	} else {
-		require.NoError(t, err)
-
-		e.mtx.RLock()
-		var id string
-		for id = range e.shards {
-			break
-		}
-		configID = calculateShardID(e.shards[id].Shard.DumpInfo())
-		e.mtx.RUnlock()
-
-		err = e.Open(context.Background())
-		if err == nil {
-			require.Error(t, e.Init(context.Background()))
-		}
-	}
+	require.NoError(t, err)
 
 	e.mtx.RLock()
-	shardCount := len(e.shards)
+	var id string
+	for id = range e.shards {
+		break
+	}
+	configID = calculateShardID(e.shards[id].Shard.DumpInfo())
 	e.mtx.RUnlock()
-	require.Equal(t, 0, shardCount)
+
+	err = e.Open(context.Background())
+	require.NoError(t, err)
+	if degradedMode {
+		require.NoError(t, e.Init(context.Background()))
+		require.Equal(t, mode.DegradedReadOnly, e.DumpInfo().Shards[0].Mode)
+		return
+	} else {
+		require.Error(t, e.Init(context.Background()))
+
+		e.mtx.RLock()
+		shardCount := len(e.shards)
+		e.mtx.RUnlock()
+		require.Equal(t, 0, shardCount)
+	}
 
 	beforeReload()
 
@@ -161,7 +158,7 @@ func testEngineFailInitAndReload(t *testing.T, errOnAdd bool, opts []shard.Optio
 	}))
 
 	e.mtx.RLock()
-	shardCount = len(e.shards)
+	shardCount := len(e.shards)
 	e.mtx.RUnlock()
 	require.Equal(t, 1, shardCount)
 }

pkg/local_object_storage/engine/shards.go

@@ -124,10 +124,10 @@ func (e *StorageEngine) createShard(ctx context.Context, opts []shard.Option) (*
 	)...)
 
 	if err := sh.UpdateID(ctx); err != nil {
-		return nil, fmt.Errorf("could not update shard ID: %w", err)
+		e.log.Warn(logs.FailedToUpdateShardID, zap.Stringer("shard_id", sh.ID()), zap.String("metabase_path", sh.DumpInfo().MetaBaseInfo.Path), zap.Error(err))
 	}
 
-	return sh, err
+	return sh, nil
 }
 
 func (e *StorageEngine) appendMetrics(id *shard.ID, opts []shard.Option) []shard.Option {

pkg/local_object_storage/shard/id.go

@@ -2,6 +2,7 @@ package shard
 
 import (
 	"context"
+	"fmt"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/util/logger"
 	"github.com/mr-tron/base58"
@@ -30,27 +31,32 @@ func (s *Shard) ID() *ID {
 
 // UpdateID reads shard ID saved in the metabase and updates it if it is missing.
 func (s *Shard) UpdateID(ctx context.Context) (err error) {
+	var metabaseOpened bool
+	var idFromMetabase []byte
 	if err = s.metaBase.Open(ctx, false); err != nil {
-		return err
+		err = fmt.Errorf("failed to open metabase: %w", err)
+	} else {
+		metabaseOpened = true
 	}
-	defer func() {
-		cErr := s.metaBase.Close()
-		if err == nil {
-			err = cErr
-		}
-	}()
-	id, err := s.metaBase.ReadShardID()
-	if err != nil {
-		return err
-	}
-	if len(id) != 0 {
-		s.info.ID = NewIDFromBytes(id)
-
-		if s.cfg.metricsWriter != nil {
-			s.cfg.metricsWriter.SetShardID(s.info.ID.String())
+	if metabaseOpened {
+		defer func() {
+			cErr := s.metaBase.Close()
+			if cErr != nil {
+				err = fmt.Errorf("failed to close metabase: %w", cErr)
+			}
+		}()
+		if idFromMetabase, err = s.metaBase.ReadShardID(); err != nil {
+			err = fmt.Errorf("failed to read shard id from metabase: %w", err)
 		}
 	}
 
+	if len(idFromMetabase) != 0 {
+		s.info.ID = NewIDFromBytes(idFromMetabase)
+	}
+
+	if s.cfg.metricsWriter != nil {
+		s.cfg.metricsWriter.SetShardID(s.info.ID.String())
+	}
 	s.log = &logger.Logger{Logger: s.log.With(zap.Stringer("shard_id", s.info.ID))}
 	s.metaBase.SetLogger(s.log)
 	s.blobStor.SetLogger(s.log)
@@ -63,8 +69,10 @@ func (s *Shard) UpdateID(ctx context.Context) (err error) {
 		s.pilorama.SetParentID(s.info.ID.String())
 	}
 
-	if len(id) != 0 {
-		return nil
+	if len(idFromMetabase) == 0 && metabaseOpened {
+		if err = s.metaBase.WriteShardID(*s.info.ID); err != nil {
+			err = fmt.Errorf("failed to write shard id to metabase: %w", err)
+		}
 	}
-	return s.metaBase.WriteShardID(*s.info.ID)
+	return
 }