[#1869] shard: Allow to reload metabase on SIGHUP

Signed-off-by: Evgenii Stratonikov <evgeniy@morphbits.ru>

CHANGELOG.md

@@ -12,6 +12,8 @@ Changelog for NeoFS Node
 - `--force` flag to `neofs-cli control set-status` command (#1916)
 
 ### Changed
+- Path to a metabase can now be reloaded with a SIGHUP.
+
 ### Fixed
 - `writecache.max_object_size` is now correctly handled (#1925)
 - Correctly handle setting ONLINE netmap status after maintenance (#1922)

pkg/local_object_storage/engine/control.go

@@ -235,10 +235,16 @@ func (rCfg *ReConfiguration) AddShard(id string, opts []shard.Option) {
 
 // Reload reloads StorageEngine's configuration in runtime.
 func (e *StorageEngine) Reload(rcfg ReConfiguration) error {
+	type reloadInfo struct {
+		sh   *shard.Shard
+		opts []shard.Option
+	}
+
 	e.mtx.RLock()
 
 	var shardsToRemove []string // shards IDs
-	var shardsToAdd []string    // meta paths
+	var shardsToAdd []string    // shard config identifiers (blobstor paths concatenation)
+	var shardsToReload []reloadInfo
 
 	// mark removed shards for removal
 	for id, sh := range e.shards {
@@ -248,27 +254,36 @@ func (e *StorageEngine) Reload(rcfg ReConfiguration) error {
 		}
 	}
 
-	// mark new shards for addition
+loop:
 	for newID := range rcfg.shards {
-		addShard := true
 		for _, sh := range e.shards {
 			// This calculation should be kept in sync with node
 			// configuration parsing during SIGHUP.
 			if newID == calculateShardID(sh.DumpInfo()) {
-				addShard = false
+				shardsToReload = append(shardsToReload, reloadInfo{
-				break
+					sh:   sh.Shard,
+					opts: rcfg.shards[newID],
+				})
+				continue loop
 			}
 		}
 
-		if addShard {
+		shardsToAdd = append(shardsToAdd, newID)
-			shardsToAdd = append(shardsToAdd, newID)
-		}
 	}
 
 	e.mtx.RUnlock()
 
 	e.removeShards(shardsToRemove...)
 
+	for _, p := range shardsToReload {
+		err := p.sh.Reload(p.opts...)
+		if err != nil {
+			e.log.Error("could not reload a shard",
+				zap.Stringer("shard id", p.sh.ID()),
+				zap.Error(err))
+		}
+	}
+
 	for _, newID := range shardsToAdd {
 		sh, err := e.createShard(rcfg.shards[newID])
 		if err != nil {

pkg/local_object_storage/metabase/control.go

@@ -1,14 +1,19 @@
 package meta
 
 import (
+	"errors"
 	"fmt"
 	"path/filepath"
 
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/shard/mode"
 	"github.com/nspcc-dev/neofs-node/pkg/util"
 	"go.etcd.io/bbolt"
 	"go.uber.org/zap"
 )
 
+// ErrDegradedMode is returned when metabase is in a degraded mode.
+var ErrDegradedMode = errors.New("metabase is in a degraded mode")
+
 // Open boltDB instance for metabase.
 func (db *DB) Open(readOnly bool) error {
 	err := util.MkdirAllX(filepath.Dir(db.info.Path), db.info.Permission)
@@ -24,6 +29,12 @@ func (db *DB) Open(readOnly bool) error {
 	}
 	db.boltOptions.ReadOnly = readOnly
 
+	return db.openBolt()
+}
+
+func (db *DB) openBolt() error {
+	var err error
+
 	db.boltDB, err = bbolt.Open(db.info.Path, db.info.Permission, db.boltOptions)
 	if err != nil {
 		return fmt.Errorf("can't open boltDB database: %w", err)
@@ -144,3 +155,36 @@ func (db *DB) Close() error {
 	}
 	return nil
 }
+
+// Reload reloads part of the configuration.
+// It returns true iff database was reopened.
+// If a config option is invalid, it logs an error and returns nil.
+// If there was a problem with applying new configuration, an error is returned.
+//
+// If a metabase was couldn't be reopened because of an error, ErrDegradedMode is returned.
+func (db *DB) Reload(opts ...Option) (bool, error) {
+	var c cfg
+	for i := range opts {
+		opts[i](&c)
+	}
+
+	db.modeMtx.Lock()
+	defer db.modeMtx.Unlock()
+
+	if c.info.Path != "" && filepath.Clean(db.info.Path) != filepath.Clean(c.info.Path) {
+		if err := db.Close(); err != nil {
+			return false, err
+		}
+
+		db.mode = mode.Degraded
+		db.info.Path = c.info.Path
+		if err := db.openBolt(); err != nil {
+			return false, fmt.Errorf("%w: %v", ErrDegradedMode, err)
+		}
+
+		db.mode = mode.ReadWrite
+		return true, nil
+	}
+
+	return false, nil
+}

pkg/local_object_storage/shard/control.go

@@ -265,3 +265,34 @@ func (s *Shard) Close() error {
 
 	return nil
 }
+
+// Reload reloads configuration portions that are necessary.
+// If a config option is invalid, it logs an error and returns nil.
+// If there was a problem with applying new configuration, an error is returned.
+func (s *Shard) Reload(opts ...Option) error {
+	// Do not use defaultCfg here missing options need not be reloaded.
+	var c cfg
+	for i := range opts {
+		opts[i](&c)
+	}
+
+	s.m.Lock()
+	defer s.m.Unlock()
+
+	ok, err := s.metaBase.Reload(c.metaOpts...)
+	if err != nil {
+		if errors.Is(err, meta.ErrDegradedMode) {
+			_ = s.setMode(mode.DegradedReadOnly)
+		}
+		return err
+	}
+	if ok {
+		if c.refillMetabase {
+			return s.refillMetabase()
+		} else {
+			return s.metaBase.Init()
+		}
+	}
+
+	return nil
+}

pkg/local_object_storage/shard/control_test.go

@@ -31,6 +31,11 @@ func (s epochState) CurrentEpoch() uint64 {
 	return 0
 }
 
+type objAddr struct {
+	obj  *objectSDK.Object
+	addr oid.Address
+}
+
 func TestShardOpen(t *testing.T) {
 	dir := t.TempDir()
 	metaPath := filepath.Join(dir, "meta")
@@ -164,11 +169,6 @@ func TestRefillMetabase(t *testing.T) {
 
 	const objNum = 5
 
-	type objAddr struct {
-		obj  *objectSDK.Object
-		addr oid.Address
-	}
-
 	mObjs := make(map[string]objAddr)
 	locked := make([]oid.ID, 1, 2)
 	locked[0] = oidtest.ID()

pkg/local_object_storage/shard/mode.go

@@ -21,6 +21,10 @@ func (s *Shard) SetMode(m mode.Mode) error {
 	s.m.Lock()
 	defer s.m.Unlock()
 
+	return s.setMode(m)
+}
+
+func (s *Shard) setMode(m mode.Mode) error {
 	components := []interface{ SetMode(mode.Mode) error }{
 		s.metaBase, s.blobStor,
 	}

pkg/local_object_storage/shard/reload_test.go

@@ -0,0 +1,143 @@
+package shard
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	objectCore "github.com/nspcc-dev/neofs-node/pkg/core/object"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/fstree"
+	meta "github.com/nspcc-dev/neofs-node/pkg/local_object_storage/metabase"
+	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/pilorama"
+	"github.com/nspcc-dev/neofs-node/pkg/util/logger"
+	checksumtest "github.com/nspcc-dev/neofs-sdk-go/checksum/test"
+	cidtest "github.com/nspcc-dev/neofs-sdk-go/container/id/test"
+	objectSDK "github.com/nspcc-dev/neofs-sdk-go/object"
+	oidtest "github.com/nspcc-dev/neofs-sdk-go/object/id/test"
+	sessiontest "github.com/nspcc-dev/neofs-sdk-go/session/test"
+	usertest "github.com/nspcc-dev/neofs-sdk-go/user/test"
+	"github.com/nspcc-dev/neofs-sdk-go/version"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/zap/zaptest"
+)
+
+func TestShardReload(t *testing.T) {
+	p := t.Name()
+	defer os.RemoveAll(p)
+
+	l := &logger.Logger{Logger: zaptest.NewLogger(t)}
+	blobOpts := []blobstor.Option{
+		blobstor.WithLogger(l),
+		blobstor.WithStorages([]blobstor.SubStorage{
+			{
+				Storage: fstree.New(
+					fstree.WithPath(filepath.Join(p, "blob")),
+					fstree.WithDepth(1)),
+			},
+		}),
+	}
+
+	metaOpts := []meta.Option{
+		meta.WithPath(filepath.Join(p, "meta")),
+		meta.WithEpochState(epochState{})}
+
+	opts := []Option{
+		WithLogger(l),
+		WithBlobStorOptions(blobOpts...),
+		WithMetaBaseOptions(metaOpts...),
+		WithPiloramaOptions(
+			pilorama.WithPath(filepath.Join(p, "pilorama")))}
+
+	sh := New(opts...)
+	require.NoError(t, sh.Open())
+	require.NoError(t, sh.Init())
+
+	objects := make([]objAddr, 5)
+	for i := range objects {
+		objects[i].obj = newObject()
+		objects[i].addr = objectCore.AddressOf(objects[i].obj)
+		require.NoError(t, putObject(sh, objects[i].obj))
+	}
+
+	checkHasObjects := func(t *testing.T, exists bool) {
+		for i := range objects {
+			var prm ExistsPrm
+			prm.SetAddress(objects[i].addr)
+
+			res, err := sh.Exists(prm)
+			require.NoError(t, err)
+			require.Equal(t, exists, res.Exists(), "object #%d is missing", i)
+		}
+	}
+
+	checkHasObjects(t, true)
+
+	t.Run("same config, no-op", func(t *testing.T) {
+		require.NoError(t, sh.Reload(opts...))
+		checkHasObjects(t, true)
+	})
+
+	t.Run("open meta at new path", func(t *testing.T) {
+		newShardOpts := func(metaPath string, resync bool) []Option {
+			metaOpts := []meta.Option{meta.WithPath(metaPath), meta.WithEpochState(epochState{})}
+			return append(opts, WithMetaBaseOptions(metaOpts...), WithRefillMetabase(resync))
+		}
+
+		newOpts := newShardOpts(filepath.Join(p, "meta1"), false)
+		require.NoError(t, sh.Reload(newOpts...))
+
+		checkHasObjects(t, false) // new path, but no resync
+
+		t.Run("can put objects", func(t *testing.T) {
+			obj := newObject()
+			require.NoError(t, putObject(sh, obj))
+			objects = append(objects, objAddr{obj: obj, addr: objectCore.AddressOf(obj)})
+		})
+
+		newOpts = newShardOpts(filepath.Join(p, "meta2"), true)
+		require.NoError(t, sh.Reload(newOpts...))
+
+		checkHasObjects(t, true) // all objects are restored, including the new one
+
+		t.Run("reload failed", func(t *testing.T) {
+			badPath := filepath.Join(p, "meta3")
+			require.NoError(t, os.WriteFile(badPath, []byte{1}, 0))
+
+			newOpts = newShardOpts(badPath, true)
+			require.Error(t, sh.Reload(newOpts...))
+
+			// Cleanup is done, no panic.
+			obj := newObject()
+			require.ErrorIs(t, putObject(sh, obj), ErrReadOnlyMode)
+
+			// Old objects are still accessible.
+			checkHasObjects(t, true)
+		})
+	})
+}
+
+func putObject(sh *Shard, obj *objectSDK.Object) error {
+	var prm PutPrm
+	prm.SetObject(obj)
+
+	_, err := sh.Put(prm)
+	return err
+}
+
+func newObject() *objectSDK.Object {
+	x := objectSDK.New()
+	ver := version.Current()
+
+	x.SetID(oidtest.ID())
+	x.SetSessionToken(sessiontest.Object())
+	x.SetPayload([]byte{1, 2, 3})
+	x.SetPayloadSize(3)
+	x.SetOwnerID(usertest.ID())
+	x.SetContainerID(cidtest.ID())
+	x.SetType(objectSDK.TypeRegular)
+	x.SetVersion(&ver)
+	x.SetPayloadChecksum(checksumtest.Checksum())
+	x.SetPayloadHomomorphicHash(checksumtest.Checksum())
+	return x
+}