Make heartbeatPeriod const into a flag.

cmd/options/options.go

@@ -83,6 +83,9 @@ type NodeProblemDetectorOptions struct {
 
 	// NodeName is the node name used to communicate with Kubernetes ApiServer.
 	NodeName string
+
+	// K8sExporterHeartbeatPeriod is the period at which the k8s exporter does forcibly sync with apiserver.
+	K8sExporterHeartbeatPeriod time.Duration
 }
 
 func NewNodeProblemDetectorOptions() *NodeProblemDetectorOptions {
@@ -120,6 +123,8 @@ func (npdo *NodeProblemDetectorOptions) AddFlags(fs *pflag.FlagSet) {
 	fs.StringVar(&npdo.PrometheusServerAddress, "prometheus-address",
 		"127.0.0.1", "The address to bind the Prometheus scrape endpoint.")
 
+	fs.DurationVar(&npdo.K8sExporterHeartbeatPeriod, "k8s-exporter-heartbeat-period", 1*time.Minute, "The period at which k8s-exporter does forcibly sync with apiserver.")
+
 	for _, exporterName := range exporters.GetExporterNames() {
 		exporterHandler := exporters.GetExporterHandlerOrDie(exporterName)
 		exporterHandler.Options.SetFlags(fs)

pkg/exporters/k8sexporter/condition/manager.go

@@ -36,8 +36,6 @@ const (
 	updatePeriod = 1 * time.Second
 	// resyncPeriod is the period at which condition manager does resync, only updates when needed.
 	resyncPeriod = 10 * time.Second
-	// heartbeatPeriod is the period at which condition manager does forcibly sync with apiserver.
-	heartbeatPeriod = 1 * time.Minute
 )
 
 // ConditionManager synchronizes node conditions with the apiserver with problem client.
@@ -75,15 +73,18 @@ type conditionManager struct {
 	client       problemclient.Client
 	updates      map[string]types.Condition
 	conditions   map[string]types.Condition
+	// heartbeatPeriod is the period at which condition manager does forcibly sync with apiserver.
+	heartbeatPeriod time.Duration
 }
 
 // NewConditionManager creates a condition manager.
-func NewConditionManager(client problemclient.Client, clock clock.Clock) ConditionManager {
+func NewConditionManager(client problemclient.Client, clock clock.Clock, heartbeatPeriod time.Duration) ConditionManager {
 	return &conditionManager{
-		client:     client,
-		clock:      clock,
-		updates:    make(map[string]types.Condition),
-		conditions: make(map[string]types.Condition),
+		client:          client,
+		clock:           clock,
+		updates:         make(map[string]types.Condition),
+		conditions:      make(map[string]types.Condition),
+		heartbeatPeriod: heartbeatPeriod,
 	}
 }
 
@@ -145,7 +146,7 @@ func (c *conditionManager) needResync() bool {
 
 // needHeartbeat checks whether a forcible heartbeat is needed.
 func (c *conditionManager) needHeartbeat() bool {
-	return c.clock.Now().Sub(c.latestTry) >= heartbeatPeriod
+	return c.clock.Now().Sub(c.latestTry) >= c.heartbeatPeriod
 }
 
 // sync synchronizes node conditions with the apiserver.

pkg/exporters/k8sexporter/condition/manager_test.go

@@ -31,10 +31,12 @@ import (
 	"k8s.io/apimachinery/pkg/util/clock"
 )
 
+const heartbeatPeriod = 1 * time.Minute
+
 func newTestManager() (*conditionManager, *problemclient.FakeProblemClient, *clock.FakeClock) {
 	fakeClient := problemclient.NewFakeProblemClient()
 	fakeClock := clock.NewFakeClock(time.Now())
-	manager := NewConditionManager(fakeClient, fakeClock)
+	manager := NewConditionManager(fakeClient, fakeClock, heartbeatPeriod)
 	return manager.(*conditionManager), fakeClient, fakeClock
 }
 

pkg/exporters/k8sexporter/k8s_exporter.go

@@ -58,7 +58,7 @@ func NewExporterOrDie(npdo *options.NodeProblemDetectorOptions) types.Exporter {
 
 	ke := k8sExporter{
 		client:           c,
-		conditionManager: condition.NewConditionManager(c, clock.RealClock{}),
+		conditionManager: condition.NewConditionManager(c, clock.RealClock{}, npdo.K8sExporterHeartbeatPeriod),
 	}
 
 	ke.startHTTPReporting(npdo)