Fix prometheus init data race

components/prometheus/collector/collection.go

@@ -1,37 +1,41 @@
 package collector
 
 import (
+	"github.com/iotaledger/hive.go/ds/shrinkingmap"
 	"github.com/iotaledger/hive.go/runtime/options"
 )
 
 type Collection struct {
 	CollectionName string
-	metrics        map[string]*Metric
+	metrics        *shrinkingmap.ShrinkingMap[string, *Metric]
 }
 
 func NewCollection(name string, opts ...options.Option[Collection]) *Collection {
 	return options.Apply(&Collection{
 		CollectionName: name,
-		metrics:        make(map[string]*Metric),
-	}, opts, func(c *Collection) {
-		for _, m := range c.metrics {
-			m.Namespace = c.CollectionName
-			m.initPromMetric()
-		}
+		metrics:        shrinkingmap.New[string, *Metric](),
+	}, opts, func(collection *Collection) {
+		collection.metrics.ForEach(func(_ string, metric *Metric) bool {
+			metric.Namespace = collection.CollectionName
+			metric.initPromMetric()
+
+			return true
+		})
 	})
 }
 
 func (c *Collection) GetMetric(metricName string) *Metric {
-	if metric, exists := c.metrics[metricName]; exists {
-		return metric
+	metric, exists := c.metrics.Get(metricName)
+	if !exists {
+		return nil
 	}
 
-	return nil
+	return metric
 }
 
 func (c *Collection) addMetric(metric *Metric) {
 	if metric != nil {
-		c.metrics[metric.Name] = metric
+		c.metrics.Set(metric.Name, metric)
 	}
 }
 

components/prometheus/collector/collector.go

@@ -2,43 +2,49 @@ package collector
 
 import (
 	"github.com/prometheus/client_golang/prometheus"
+
+	"github.com/iotaledger/hive.go/ds/shrinkingmap"
 )
 
 // Collector is responsible for creation and collection of metrics for the prometheus.
 type Collector struct {
 	Registry    *prometheus.Registry
-	collections map[string]*Collection
+	collections *shrinkingmap.ShrinkingMap[string, *Collection]
 }
 
 // New creates an instance of Manager and creates a new prometheus registry for the protocol metrics collection.
 func New() *Collector {
 	return &Collector{
 		Registry:    prometheus.NewRegistry(),
-		collections: make(map[string]*Collection),
+		collections: shrinkingmap.New[string, *Collection](),
 	}
 }
 
-func (c *Collector) RegisterCollection(coll *Collection) {
-	c.collections[coll.CollectionName] = coll
-	for _, m := range coll.metrics {
-		c.Registry.MustRegister(m.promMetric)
-		if m.initValueFunc != nil {
-			metricValue, labelValues := m.initValueFunc()
-			m.update(metricValue, labelValues...)
+func (c *Collector) RegisterCollection(collection *Collection) {
+	c.collections.Set(collection.CollectionName, collection)
+	collection.metrics.ForEach(func(_ string, metric *Metric) bool {
+		c.Registry.MustRegister(metric.promMetric)
+		if metric.initValueFunc != nil {
+			metricValue, labelValues := metric.initValueFunc()
+			metric.update(metricValue, labelValues...)
 		}
-		if m.initFunc != nil {
-			m.initFunc()
+		if metric.initFunc != nil {
+			metric.initFunc()
 		}
-	}
+
+		return true
+	})
 }
 
 // Collect collects all metrics from the registered collections.
 func (c *Collector) Collect() {
-	for _, collection := range c.collections {
-		for _, metric := range collection.metrics {
+	c.collections.ForEach(func(_ string, collection *Collection) bool {
+		collection.metrics.ForEach(func(_ string, metric *Metric) bool {
 			metric.collect()
-		}
-	}
+			return true
+		})
+		return true
+	})
 }
 
 // Update updates the value of the existing metric defined by the subsystem and metricName.
@@ -78,11 +84,13 @@ func (c *Collector) ResetMetric(namespace string, metricName string) {
 }
 
 func (c *Collector) Shutdown() {
-	for _, collection := range c.collections {
-		for _, metric := range collection.metrics {
+	c.collections.ForEach(func(_ string, collection *Collection) bool {
+		collection.metrics.ForEach(func(_ string, metric *Metric) bool {
 			metric.shutdown()
-		}
-	}
+			return true
+		})
+		return true
+	})
 }
 
 func (c *Collector) getMetric(subsystem string, metricName string) *Metric {
@@ -95,9 +103,10 @@ func (c *Collector) getMetric(subsystem string, metricName string) *Metric {
 }
 
 func (c *Collector) getCollection(subsystem string) *Collection {
-	if collection, exists := c.collections[subsystem]; exists {
-		return collection
+	collection, exists := c.collections.Get(subsystem)
+	if !exists {
+		return nil
 	}
 
-	return nil
+	return collection
 }

components/prometheus/component.go

@@ -29,11 +29,12 @@ import (
 
 func init() {
 	Component = &app.Component{
-		Name:     "Prometheus",
-		DepsFunc: func(cDeps dependencies) { deps = cDeps },
-		Params:   params,
-		Provide:  provide,
-		Run:      run,
+		Name:      "Prometheus",
+		DepsFunc:  func(cDeps dependencies) { deps = cDeps },
+		Params:    params,
+		Provide:   provide,
+		Configure: configure,
+		Run:       run,
 		IsEnabled: func(_ *dig.Container) bool {
 			return ParamsMetrics.Enabled
 		},
@@ -56,17 +57,32 @@ type dependencies struct {
 	Collector *collector.Collector
 }
 
-func run() error {
-	Component.LogInfo("Starting Prometheus exporter ...")
+func provide(c *dig.Container) error {
+	return c.Provide(collector.New)
+}
 
+func configure() error {
 	if ParamsMetrics.GoMetrics {
 		deps.Collector.Registry.MustRegister(collectors.NewGoCollector())
 	}
 	if ParamsMetrics.ProcessMetrics {
 		deps.Collector.Registry.MustRegister(collectors.NewProcessCollector(collectors.ProcessCollectorOpts{}))
 	}
 
-	registerMetrics()
+	deps.Collector.RegisterCollection(TangleMetrics)
+	deps.Collector.RegisterCollection(ConflictMetrics)
+	deps.Collector.RegisterCollection(InfoMetrics)
+	deps.Collector.RegisterCollection(DBMetrics)
+	deps.Collector.RegisterCollection(CommitmentsMetrics)
+	deps.Collector.RegisterCollection(SlotMetrics)
+	deps.Collector.RegisterCollection(AccountMetrics)
+	deps.Collector.RegisterCollection(SchedulerMetrics)
+
+	return nil
+}
+
+func run() error {
+	Component.LogInfo("Starting Prometheus exporter ...")
 
 	return Component.Daemon().BackgroundWorker("Prometheus exporter", func(ctx context.Context) {
 		Component.LogInfo("Starting Prometheus exporter ... done")
@@ -118,18 +134,3 @@ func run() error {
 		Component.LogInfo("Stopping Prometheus exporter ... done")
 	}, daemon.PriorityMetrics)
 }
-
-func provide(c *dig.Container) error {
-	return c.Provide(collector.New)
-}
-
-func registerMetrics() {
-	deps.Collector.RegisterCollection(TangleMetrics)
-	deps.Collector.RegisterCollection(ConflictMetrics)
-	deps.Collector.RegisterCollection(InfoMetrics)
-	deps.Collector.RegisterCollection(DBMetrics)
-	deps.Collector.RegisterCollection(CommitmentsMetrics)
-	deps.Collector.RegisterCollection(SlotMetrics)
-	deps.Collector.RegisterCollection(AccountMetrics)
-	deps.Collector.RegisterCollection(SchedulerMetrics)
-}