metrics/ir: neofs_ir_state_health metric

Expose health status via Prometheus.

Signed-off-by: Andrey Butusov <[email protected]>

CHANGELOG.md

@@ -5,6 +5,8 @@ Changelog for NeoFS Node
 
 ### Added
 - More effective FSTree writer for HDDs, new configuration options for it (#2814)
+- New health status `CREATE_SERVER` in inner ring (#2934)
+- Expose health status of inner ring via Prometheus (#2934)
 
 ### Fixed
 

pkg/innerring/state.go

@@ -201,6 +201,9 @@ func (s *Server) ResetEpochTimer(h uint32) error {
 
 func (s *Server) setHealthStatus(hs control.HealthStatus) {
 	s.healthStatus.Store(hs)
+	if s.metrics != nil {
+		s.metrics.SetHealthCheck(int32(hs))
+	}
 }
 
 // HealthStatus returns the current health status of the IR application.

pkg/metrics/innerring.go

@@ -8,7 +8,8 @@ const innerRingNameSpace = "neofs_ir"
 
 // InnerRingServiceMetrics contains metrics collected by inner ring.
 type InnerRingServiceMetrics struct {
-	epoch prometheus.Gauge
+	epoch       prometheus.Gauge
+	healthCheck prometheus.Gauge
 }
 
 // NewInnerRingMetrics returns new instance of metrics collectors for inner ring.
@@ -23,12 +24,25 @@ func NewInnerRingMetrics(version string) InnerRingServiceMetrics {
 	})
 	prometheus.MustRegister(epoch)
 
+	healthCheck := prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace: innerRingNameSpace,
+		Subsystem: stateSubsystem,
+		Name:      "health",
+		Help:      "Current ir state",
+	})
+	prometheus.MustRegister(healthCheck)
+
 	return InnerRingServiceMetrics{
-		epoch: epoch,
+		epoch:       epoch,
+		healthCheck: healthCheck,
 	}
 }
 
 // SetEpoch updates epoch metrics.
 func (m InnerRingServiceMetrics) SetEpoch(epoch uint64) {
 	m.epoch.Set(float64(epoch))
 }
+
+func (m InnerRingServiceMetrics) SetHealthCheck(healthCheck int32) {
+	m.healthCheck.Set(float64(healthCheck))
+}