[#1658] node: Support object counter metrics

Increment shard's object counter on successful `Put` calls and decrement on
`Delete`.

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

pkg/local_object_storage/engine/metrics.go

@@ -16,6 +16,8 @@ type MetricRegister interface {
 	AddRangeDuration(d time.Duration)
 	AddSearchDuration(d time.Duration)
 	AddListObjectsDuration(d time.Duration)
+
+	AddToObjectCounter(shardID string, delta int)
 }
 
 func elapsed(addFunc func(d time.Duration)) func() {

pkg/local_object_storage/engine/shards.go

@@ -17,6 +17,23 @@ var errShardNotFound = errors.New("shard not found")
 
 type hashedShard shardWrapper
 
+type metricsWithID struct {
+	id string
+	mw MetricRegister
+}
+
+func (m metricsWithID) AddToObjectCounter(delta int) {
+	m.mw.AddToObjectCounter(m.id, delta)
+}
+
+func (m metricsWithID) IncObjectCounter() {
+	m.mw.AddToObjectCounter(m.id, +1)
+}
+
+func (m metricsWithID) DecObjectCounter() {
+	m.mw.AddToObjectCounter(m.id, -1)
+}
+
 // AddShard adds a new shard to the storage engine.
 //
 // Returns any error encountered that did not allow adding a shard.
@@ -35,6 +52,15 @@ func (e *StorageEngine) AddShard(opts ...shard.Option) (*shard.ID, error) {
 		return nil, fmt.Errorf("could not generate shard ID: %w", err)
 	}
 
+	if e.metrics != nil {
+		opts = append(opts, shard.WithMetricsWriter(
+			metricsWithID{
+				id: id.String(),
+				mw: e.metrics,
+			},
+		))
+	}
+
 	sh := shard.New(append(opts,
 		shard.WithID(id),
 		shard.WithExpiredTombstonesCallback(e.processExpiredTombstones),

pkg/local_object_storage/metabase/delete.go

@@ -11,7 +11,6 @@ import (
 	objectSDK "github.com/nspcc-dev/neofs-sdk-go/object"
 	oid "github.com/nspcc-dev/neofs-sdk-go/object/id"
 	"go.etcd.io/bbolt"
-	"go.uber.org/zap"
 )
 
 // DeletePrm groups the parameters of Delete operation.
@@ -20,7 +19,14 @@ type DeletePrm struct {
 }
 
 // DeleteRes groups the resulting values of Delete operation.
-type DeleteRes struct{}
+type DeleteRes struct {
+	removed uint64
+}
+
+// RemovedObjects returns number of removed raw objects.
+func (d DeleteRes) RemovedObjects() uint64 {
+	return d.removed
+}
 
 // SetAddresses is a Delete option to set the addresses of the objects to delete.
 //
@@ -44,8 +50,12 @@ func (db *DB) Delete(prm DeletePrm) (DeleteRes, error) {
 	db.modeMtx.RLock()
 	defer db.modeMtx.RUnlock()
 
-	err := db.boltDB.Update(func(tx *bbolt.Tx) error {
-		return db.deleteGroup(tx, prm.addrs)
+	var rawRemoved uint64
+	var err error
+
+	err = db.boltDB.Update(func(tx *bbolt.Tx) error {
+		rawRemoved, err = db.deleteGroup(tx, prm.addrs)
+		return err
 	})
 	if err == nil {
 		for i := range prm.addrs {
@@ -54,10 +64,10 @@ func (db *DB) Delete(prm DeletePrm) (DeleteRes, error) {
 				storagelog.OpField("metabase DELETE"))
 		}
 	}
-	return DeleteRes{}, err
+	return DeleteRes{removed: rawRemoved}, err
 }
 
-func (db *DB) deleteGroup(tx *bbolt.Tx, addrs []oid.Address) error {
+func (db *DB) deleteGroup(tx *bbolt.Tx, addrs []oid.Address) (uint64, error) {
 	refCounter := make(referenceCounter, len(addrs))
 	currEpoch := db.epochState.CurrentEpoch()
 
@@ -65,7 +75,7 @@ func (db *DB) deleteGroup(tx *bbolt.Tx, addrs []oid.Address) error {
 	for i := range addrs {
 		removed, err := db.delete(tx, addrs[i], refCounter, currEpoch)
 		if err != nil {
-			return err // maybe log and continue?
+			return 0, err // maybe log and continue?
 		}
 
 		if removed {
@@ -75,20 +85,19 @@ func (db *DB) deleteGroup(tx *bbolt.Tx, addrs []oid.Address) error {
 
 	err := db.updateCounter(tx, rawDeleted, false)
 	if err != nil {
-		db.log.Error("could not decrease object counter",
-			zap.Error(err))
+		return 0, fmt.Errorf("could not decrease object counter: %w", err)
 	}
 
 	for _, refNum := range refCounter {
 		if refNum.cur == refNum.all {
 			err := db.deleteObject(tx, refNum.obj, true)
 			if err != nil {
-				return err // maybe log and continue?
+				return rawDeleted, err // maybe log and continue?
 			}
 		}
 	}
 
-	return nil
+	return rawDeleted, nil
 }
 
 func (db *DB) delete(tx *bbolt.Tx, addr oid.Address, refCounter referenceCounter, currEpoch uint64) (bool, error) {

pkg/local_object_storage/metabase/put.go

@@ -14,7 +14,6 @@ import (
 	objectSDK "github.com/nspcc-dev/neofs-sdk-go/object"
 	oid "github.com/nspcc-dev/neofs-sdk-go/object/id"
 	"go.etcd.io/bbolt"
-	"go.uber.org/zap"
 )
 
 type (
@@ -146,8 +145,7 @@ func (db *DB) put(
 	if !isParent {
 		err = db.updateCounter(tx, 1, true)
 		if err != nil {
-			db.log.Error("could not increase object counter: %w",
-				zap.Error(err))
+			return fmt.Errorf("could not increase object counter: %w", err)
 		}
 	}
 

pkg/local_object_storage/shard/delete.go

@@ -65,11 +65,13 @@ func (s *Shard) Delete(prm DeletePrm) (DeleteRes, error) {
 	var delPrm meta.DeletePrm
 	delPrm.SetAddresses(prm.addr...)
 
-	_, err := s.metaBase.Delete(delPrm)
+	res, err := s.metaBase.Delete(delPrm)
 	if err != nil {
 		return DeleteRes{}, err // stop on metabase error ?
 	}
 
+	s.decObjectCounterBy(res.RemovedObjects())
+
 	for i := range prm.addr { // delete small object
 		var delPrm common.DeletePrm
 		delPrm.Address = prm.addr[i]

pkg/local_object_storage/shard/put.go

@@ -73,6 +73,8 @@ func (s *Shard) Put(prm PutPrm) (PutRes, error) {
 			// since the object has been successfully written to BlobStor
 			return PutRes{}, fmt.Errorf("could not put object to metabase: %w", err)
 		}
+
+		s.incObjectCounter()
 	}
 
 	return PutRes{}, nil

pkg/local_object_storage/shard/shard.go

@@ -45,6 +45,17 @@ type ExpiredObjectsCallback func(context.Context, []oid.Address)
 // DeletedLockCallback is a callback handling list of deleted LOCK objects.
 type DeletedLockCallback func(context.Context, []oid.Address)
 
+// MetricsWriter is an interface that must store shard's metrics.
+type MetricsWriter interface {
+	// AddToObjectCounter must update object counter. Negative
+	// parameter must decrease the counter.
+	AddToObjectCounter(delta int)
+	// IncObjectCounter must increment shard's object counter.
+	IncObjectCounter()
+	// DecObjectCounter must decrement shard's object counter.
+	DecObjectCounter()
+}
+
 type cfg struct {
 	m sync.RWMutex
 
@@ -75,6 +86,8 @@ type cfg struct {
 	deletedLockCallBack DeletedLockCallback
 
 	tsSource TombstoneSource
+
+	metricsWriter MetricsWriter
 }
 
 func defaultCfg() *cfg {
@@ -259,6 +272,14 @@ func WithDeletedLockCallback(v DeletedLockCallback) Option {
 	}
 }
 
+// WithMetricsWriter returns option to specify storage of the
+// shard's metrics.
+func WithMetricsWriter(v MetricsWriter) Option {
+	return func(c *cfg) {
+		c.metricsWriter = v
+	}
+}
+
 func (s *Shard) fillInfo() {
 	s.cfg.info.MetaBaseInfo = s.metaBase.DumpInfo()
 	s.cfg.info.BlobStorInfo = s.blobStor.DumpInfo()
@@ -271,3 +292,15 @@ func (s *Shard) fillInfo() {
 		s.cfg.info.PiloramaInfo = s.pilorama.DumpInfo()
 	}
 }
+
+func (s *Shard) incObjectCounter() {
+	if s.cfg.metricsWriter != nil {
+		s.cfg.metricsWriter.IncObjectCounter()
+	}
+}
+
+func (s *Shard) decObjectCounterBy(v uint64) {
+	if s.cfg.metricsWriter != nil {
+		s.cfg.metricsWriter.AddToObjectCounter(-int(v))
+	}
+}