events: fix for G104 (CWE-703)

Reported by gosec.

G104 (CWE-703): Errors unhandled. (Confidence: HIGH, Severity: LOW)

This commit handles the previously ignored errors.

cmd/event-logger/app/options.go

@@ -182,7 +182,10 @@ func (o *Options) Run(stopCh <-chan struct{}) error {
 		return err
 	}
 
-	eventLogger := config.New()
+	eventLogger, err := config.New()
+	if err != nil {
+		return err
+	}
 
 	eventLogger.Run(stopCh)
 

pkg/events/events_logger.go

@@ -17,7 +17,7 @@ import (
 )
 
 // NewEventInformerFuncForNamespace returns function which creates new event informer for a given namespace.
-func NewEventInformerFuncForNamespace(origin, namespace string) kubeinformersinterfaces.NewInformerFunc {
+func NewEventInformerFuncForNamespace(namespace string) kubeinformersinterfaces.NewInformerFunc {
 	return func(clientset kubernetes.Interface, resyncPeriod time.Duration) cache.SharedIndexInformer {
 		watchlist := cache.NewListWatchFromClient(
 			clientset.CoreV1().RESTClient(),
@@ -31,24 +31,30 @@ func NewEventInformerFuncForNamespace(origin, namespace string) kubeinformersint
 			resyncPeriod,
 			cache.Indexers{},
 		)
-		informer.AddEventHandler(cache.ResourceEventHandlerFuncs{
-			AddFunc: func(obj interface{}) {
-				if isV1Event(obj) {
-					v1Event := obj.(*v1.Event)
-					printV1Event(v1Event, origin)
-				}
-			},
-			UpdateFunc: func(_ interface{}, newObject interface{}) {
-				if isV1Event(newObject) {
-					v1Event := newObject.(*v1.Event)
-					printV1Event(v1Event, origin)
-				}
-			},
-		})
+
 		return informer
 	}
 }
 
+func addEventHandler(informer cache.SharedIndexInformer, origin string) error {
+	_, err := informer.AddEventHandler(cache.ResourceEventHandlerFuncs{
+		AddFunc: func(obj interface{}) {
+			if isV1Event(obj) {
+				v1Event := obj.(*v1.Event)
+				printV1Event(v1Event, origin)
+			}
+		},
+		UpdateFunc: func(_ interface{}, newObject interface{}) {
+			if isV1Event(newObject) {
+				v1Event := newObject.(*v1.Event)
+				printV1Event(v1Event, origin)
+			}
+		},
+	})
+
+	return err
+}
+
 func isV1Event(obj interface{}) bool {
 	_, ok := obj.(*v1.Event)
 	return ok

pkg/events/gardener_event_watcher.go

@@ -30,31 +30,35 @@ type GardenerEventWatcher struct {
 }
 
 // New returns new GardenerEventWatcherConfig
-func (e *GardenerEventWatcherConfig) New() *GardenerEventWatcher {
+func (e *GardenerEventWatcherConfig) New() (*GardenerEventWatcher, error) {
 	for indx, namespace := range e.SeedEventWatcherConfig.Namespaces {
-		_ = e.SeedKubeInformerFactories[indx].InformerFor(&v1.Event{},
-			NewEventInformerFuncForNamespace(
-				"seed",
-				namespace,
-			),
+		informer := e.SeedKubeInformerFactories[indx].InformerFor(
+			&v1.Event{},
+			NewEventInformerFuncForNamespace(namespace),
 		)
+		if err := addEventHandler(informer, "seed"); err != nil {
+			return nil, err
+		}
 	}
 
 	if e.ShootEventWatcherConfig.Kubeconfig != "" {
 		for indx, namespace := range e.ShootEventWatcherConfig.Namespaces {
-			_ = e.ShootKubeInformerFactories[indx].InformerFor(&v1.Event{},
-				NewEventInformerFuncForNamespace(
-					"shoot",
-					namespace,
-				),
+			informer := e.ShootKubeInformerFactories[indx].InformerFor(
+				&v1.Event{},
+				NewEventInformerFuncForNamespace(namespace),
 			)
+			if err := addEventHandler(informer, "shoot"); err != nil {
+				return nil, err
+			}
 		}
 	}
 
-	return &GardenerEventWatcher{
+	watcher := &GardenerEventWatcher{
 		SeedKubeInformerFactories:  e.SeedKubeInformerFactories,
 		ShootKubeInformerFactories: e.ShootKubeInformerFactories,
 	}
+
+	return watcher, nil
 }
 
 // Run start the GardenerEventWatcher lifecycle