From 270365c864e0509c38995f84e5277ebbd4b51f1f Mon Sep 17 00:00:00 2001
From: Carlos Panato <ctadeu@gmail.com>
Date: Wed, 29 Jan 2020 10:14:12 +0100
Subject: [PATCH] Health: Add liveness and readiness probes

---
 config/manager/manager.yaml | 12 ++++++++++++
 main.go                     | 31 +++++++++++++++++++++++++------
 2 files changed, 37 insertions(+), 6 deletions(-)

diff --git a/config/manager/manager.yaml b/config/manager/manager.yaml
index 8a8bf5d888c..9b2e668500c 100644
--- a/config/manager/manager.yaml
+++ b/config/manager/manager.yaml
@@ -28,4 +28,16 @@ spec:
         image: controller:latest
         imagePullPolicy: Always
         name: manager
+        ports:
+        - containerPort: 9440
+          name: healthz
+          protocol: TCP
+        readinessProbe:
+          httpGet:
+            path: /readyz
+            port: healthz
+        livenessProbe:
+          httpGet:
+            path: /healthz
+            port: healthz
       terminationGracePeriodSeconds: 10
diff --git a/main.go b/main.go
index ec678d3c01f..61db300b401 100644
--- a/main.go
+++ b/main.go
@@ -34,6 +34,7 @@ import (
 	"sigs.k8s.io/cluster-api/util/record"
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/controller"
+	"sigs.k8s.io/controller-runtime/pkg/healthz"
 	// +kubebuilder:scaffold:imports
 )
 
@@ -61,6 +62,7 @@ func main() {
 		azureClusterConcurrency int
 		azureMachineConcurrency int
 		syncPeriod              time.Duration
+		healthAddr              string
 	)
 
 	flag.StringVar(
@@ -109,6 +111,12 @@ func main() {
 		"The minimum interval at which watched resources are reconciled (e.g. 15m)",
 	)
 
+	flag.StringVar(&healthAddr,
+		"health-addr",
+		":9440",
+		"The address the health endpoint binds to.",
+	)
+
 	flag.Parse()
 
 	if watchNamespace != "" {
@@ -125,12 +133,13 @@ func main() {
 	ctrl.SetLogger(klogr.New())
 
 	mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{
-		Scheme:             scheme,
-		MetricsBindAddress: metricsAddr,
-		LeaderElection:     enableLeaderElection,
-		LeaderElectionID:   "controller-leader-election-capz",
-		SyncPeriod:         &syncPeriod,
-		Namespace:          watchNamespace,
+		Scheme:                 scheme,
+		MetricsBindAddress:     metricsAddr,
+		LeaderElection:         enableLeaderElection,
+		LeaderElectionID:       "controller-leader-election-capz",
+		SyncPeriod:             &syncPeriod,
+		Namespace:              watchNamespace,
+		HealthProbeBindAddress: healthAddr,
 	})
 	if err != nil {
 		setupLog.Error(err, "unable to start manager")
@@ -156,6 +165,16 @@ func main() {
 	}
 	// +kubebuilder:scaffold:builder
 
+	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)
+	}
+
 	setupLog.Info("starting manager")
 	if err := mgr.Start(ctrl.SetupSignalHandler()); err != nil {
 		setupLog.Error(err, "problem running manager")