✨ Add liveness/readiness probes

cmd/example-provider/main.go

@@ -26,6 +26,7 @@ import (
 	"sigs.k8s.io/cluster-api/controllers"
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/controller"
+	"sigs.k8s.io/controller-runtime/pkg/healthz"
 )
 
 func main() {
@@ -34,17 +35,21 @@ func main() {
 	flag.BoolVar(&enableLeaderElection, "enable-leader-election", false,
 		"Enable leader election for controller manager. Enabling this will ensure there is only one active controller manager.")
 	var metricsAddr string
+	var healthAddr string
 	flag.StringVar(&metricsAddr, "metrics-addr", ":8080",
 		"The address the metric endpoint binds to.")
+	flag.StringVar(&healthAddr, "health-addr", ":9440",
+		"The address the health endpoint binds to.")
 	flag.Parse()
 
 	cfg := ctrl.GetConfigOrDie()
 
 	// Setup a Manager
 	mgr, err := ctrl.NewManager(cfg, ctrl.Options{
-		Scheme:             scheme.Scheme,
-		LeaderElection:     enableLeaderElection,
-		MetricsBindAddress: metricsAddr,
+		Scheme:                 scheme.Scheme,
+		LeaderElection:         enableLeaderElection,
+		MetricsBindAddress:     metricsAddr,
+		HealthProbeBindAddress: healthAddr,
 	})
 	if err != nil {
 		klog.Fatalf("Failed to set up controller manager: %v", err)
@@ -67,6 +72,14 @@ func main() {
 		os.Exit(1)
 	}
 
+	if err := mgr.AddReadyzCheck("ping", healthz.Ping); err != nil {
+		klog.Fatalf("unable to create health check: %v", err)
+	}
+
+	if err := mgr.AddHealthzCheck("ping", healthz.Ping); err != nil {
+		klog.Fatalf("unable to create health check: %v", err)
+	}
+
 	if err := mgr.Start(ctrl.SetupSignalHandler()); err != nil {
 		klog.Fatalf("Failed to run manager: %v", err)
 	}

config/manager/manager.yaml

@@ -29,6 +29,18 @@ spec:
         - --enable-leader-election
         image: controller:latest
         name: manager
+        ports:
+        - containerPort: 9440
+          name: healthz
+          protocol: TCP
+        readinessProbe:
+          httpGet:
+            path: /readyz
+            port: healthz
+        livenessProbe:
+          httpGet:
+            path: /healthz
+            port: healthz
       terminationGracePeriodSeconds: 10
       tolerations:
         - effect: NoSchedule

main.go

@@ -35,6 +35,7 @@ import (
 	clusterv1alpha2 "sigs.k8s.io/cluster-api/api/v1alpha2"
 	clusterv1alpha3 "sigs.k8s.io/cluster-api/api/v1alpha3"
 	"sigs.k8s.io/cluster-api/controllers"
+	"sigs.k8s.io/controller-runtime/pkg/healthz"
 	// +kubebuilder:scaffold:imports
 )
 
@@ -65,6 +66,7 @@ func main() {
 		machinePoolConcurrency       int
 		syncPeriod                   time.Duration
 		webhookPort                  int
+		healthAddr                   string
 	)
 
 	flag.StringVar(&metricsAddr, "metrics-addr", ":8080",
@@ -100,6 +102,9 @@ func main() {
 	flag.IntVar(&webhookPort, "webhook-port", 9443,
 		"Webhook Server port (set to 0 to disable)")
 
+	flag.StringVar(&healthAddr, "health-addr", ":9440",
+		"The address the health endpoint binds to.")
+
 	flag.Parse()
 
 	ctrl.SetLogger(klogr.New())
@@ -112,14 +117,15 @@ func main() {
 	}
 
 	mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{
-		Scheme:             scheme,
-		MetricsBindAddress: metricsAddr,
-		LeaderElection:     enableLeaderElection,
-		LeaderElectionID:   "controller-leader-election-capi",
-		Namespace:          watchNamespace,
-		SyncPeriod:         &syncPeriod,
-		NewClient:          newClientFunc,
-		Port:               webhookPort,
+		Scheme:                 scheme,
+		MetricsBindAddress:     metricsAddr,
+		LeaderElection:         enableLeaderElection,
+		LeaderElectionID:       "controller-leader-election-capi",
+		Namespace:              watchNamespace,
+		SyncPeriod:             &syncPeriod,
+		NewClient:              newClientFunc,
+		Port:                   webhookPort,
+		HealthProbeBindAddress: healthAddr,
 	})
 	if err != nil {
 		setupLog.Error(err, "unable to start manager")
@@ -225,6 +231,16 @@ func main() {
 		}
 	}
 
+	if err := mgr.AddReadyzCheck("ping", healthz.Ping); err != nil {
+		setupLog.Error(err, "unable to create ready check")
+		os.Exit(1)
+	}
+
+	if err := mgr.AddHealthzCheck("ping", healthz.Ping); err != nil {
+		setupLog.Error(err, "unable to create health check")
+		os.Exit(1)
+	}
+
 	// +kubebuilder:scaffold:builder
 	setupLog.Info("starting manager")
 	if err := mgr.Start(ctrl.SetupSignalHandler()); err != nil {