[#1658] node: Read metrics from meta on startup

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

pkg/local_object_storage/engine/metrics.go

@@ -17,6 +17,7 @@ type MetricRegister interface {
 	AddSearchDuration(d time.Duration)
 	AddListObjectsDuration(d time.Duration)
 
+	SetObjectCounter(shardID string, v uint64)
 	AddToObjectCounter(shardID string, delta int)
 }
 

pkg/local_object_storage/engine/shards.go

@@ -22,6 +22,10 @@ type metricsWithID struct {
 	mw MetricRegister
 }
 
+func (m metricsWithID) SetObjectCounter(v uint64) {
+	m.mw.SetObjectCounter(m.id, v)
+}
+
 func (m metricsWithID) AddToObjectCounter(delta int) {
 	m.mw.AddToObjectCounter(m.id, delta)
 }

pkg/local_object_storage/shard/control.go

@@ -120,6 +120,8 @@ func (s *Shard) Init() error {
 		}
 	}
 
+	s.updateObjectCounter()
+
 	s.gc = &gc{
 		gcCfg:       s.gcCfg,
 		remover:     s.removeGarbage,

pkg/local_object_storage/shard/shard.go

@@ -47,6 +47,8 @@ type DeletedLockCallback func(context.Context, []oid.Address)
 
 // MetricsWriter is an interface that must store shard's metrics.
 type MetricsWriter interface {
+	// SetObjectCounter must set object counter.
+	SetObjectCounter(v uint64)
 	// AddToObjectCounter must update object counter. Negative
 	// parameter must decrease the counter.
 	AddToObjectCounter(delta int)
@@ -293,6 +295,21 @@ func (s *Shard) fillInfo() {
 	}
 }
 
+func (s *Shard) updateObjectCounter() {
+	if s.cfg.metricsWriter != nil && !s.GetMode().NoMetabase() {
+		c, err := s.metaBase.ObjectCounter()
+		if err != nil {
+			s.log.Warn("meta: object counter read",
+				zap.Error(err),
+			)
+
+			return
+		}
+
+		s.cfg.metricsWriter.SetObjectCounter(c)
+	}
+}
+
 func (s *Shard) incObjectCounter() {
 	if s.cfg.metricsWriter != nil {
 		s.cfg.metricsWriter.IncObjectCounter()

pkg/metrics/object.go

@@ -274,3 +274,7 @@ func (m objectServiceMetrics) AddGetPayload(ln int) {
 func (m objectServiceMetrics) AddToObjectCounter(shardID string, delta int) {
 	m.shardMetrics.With(prometheus.Labels{shardIDLabelKey: shardID}).Add(float64(delta))
 }
+
+func (m objectServiceMetrics) SetObjectCounter(shardID string, v uint64) {
+	m.shardMetrics.With(prometheus.Labels{shardIDLabelKey: shardID}).Set(float64(v))
+}