From 4e4a5900007ee1a34368355a476ffb11ffe777b1 Mon Sep 17 00:00:00 2001
From: Zbynek Roubalik <zroubali@redhat.com>
Date: Wed, 29 Apr 2020 12:23:33 +0200
Subject: [PATCH] adding liveness and readiness probes

Signed-off-by: Zbynek Roubalik <zroubali@redhat.com>
---
 cmd/manager/main.go               | 26 ++++++++++++++++++++------
 deploy/12-operator.yaml           | 10 ++++++++++
 deploy/22-metrics-deployment.yaml | 12 ++++++++++++
 3 files changed, 42 insertions(+), 6 deletions(-)

diff --git a/cmd/manager/main.go b/cmd/manager/main.go
index 460fbf17e9c..ce7a4657361 100644
--- a/cmd/manager/main.go
+++ b/cmd/manager/main.go
@@ -9,10 +9,6 @@ import (
 	"runtime"
 	"strings"
 
-	// Import all Kubernetes client auth plugins (e.g. Azure, GCP, OIDC, etc.)
-	_ "k8s.io/client-go/plugin/pkg/client/auth"
-	"k8s.io/client-go/rest"
-
 	"github.com/kedacore/keda/pkg/apis"
 	"github.com/kedacore/keda/pkg/controller"
 	"github.com/kedacore/keda/version"
@@ -26,8 +22,11 @@ import (
 	"github.com/spf13/pflag"
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/util/intstr"
+	_ "k8s.io/client-go/plugin/pkg/client/auth"
+	"k8s.io/client-go/rest"
 	"sigs.k8s.io/controller-runtime/pkg/cache"
 	"sigs.k8s.io/controller-runtime/pkg/client/config"
+	"sigs.k8s.io/controller-runtime/pkg/healthz"
 	logf "sigs.k8s.io/controller-runtime/pkg/log"
 	"sigs.k8s.io/controller-runtime/pkg/manager"
 	"sigs.k8s.io/controller-runtime/pkg/manager/signals"
@@ -95,8 +94,9 @@ func main() {
 
 	// Set default manager options
 	options := manager.Options{
-		Namespace:          namespace,
-		MetricsBindAddress: fmt.Sprintf("%s:%d", metricsHost, metricsPort),
+		Namespace:              namespace,
+		MetricsBindAddress:     fmt.Sprintf("%s:%d", metricsHost, metricsPort),
+		HealthProbeBindAddress: ":8080",
 	}
 
 	// Add support for MultiNamespace set in WATCH_NAMESPACE (e.g ns1,ns2)
@@ -115,6 +115,20 @@ func main() {
 		os.Exit(1)
 	}
 
+	// Add readiness probe
+	err = mgr.AddReadyzCheck("ready-ping", healthz.Ping)
+	if err != nil {
+		log.Error(err, "Unable to add a readiness check")
+		os.Exit(1)
+	}
+
+	// Add liveness probe
+	err = mgr.AddHealthzCheck("health-ping", healthz.Ping)
+	if err != nil {
+		log.Error(err, "Unable to add a health check")
+		os.Exit(1)
+	}
+
 	log.Info("Registering Components.")
 
 	// Setup Scheme for all resources
diff --git a/deploy/12-operator.yaml b/deploy/12-operator.yaml
index c99d14d411e..1a17e0b2f03 100644
--- a/deploy/12-operator.yaml
+++ b/deploy/12-operator.yaml
@@ -31,6 +31,16 @@ spec:
           - '--zap-level=info'
           - '--zap-time-encoding=epoch'
           imagePullPolicy: Always
+          livenessProbe:
+            httpGet:
+              path: /healthz
+              port: 8080
+            initialDelaySeconds: 25
+          readinessProbe:
+            httpGet:
+              path: /readyz
+              port: 8080
+            initialDelaySeconds: 20
           env:
             - name: WATCH_NAMESPACE
               value: ""
diff --git a/deploy/22-metrics-deployment.yaml b/deploy/22-metrics-deployment.yaml
index a7fed57c54f..cc7c443ce29 100644
--- a/deploy/22-metrics-deployment.yaml
+++ b/deploy/22-metrics-deployment.yaml
@@ -24,6 +24,18 @@ spec:
         - name: keda-metrics-apiserver
           image: docker.io/kedacore/keda-metrics-adapter:2.0.0-alpha1
           imagePullPolicy: Always
+          livenessProbe:
+            httpGet:
+              scheme: HTTPS
+              path: /healthz
+              port: 6443
+            initialDelaySeconds: 5
+          readinessProbe:
+            httpGet:
+              scheme: HTTPS
+              path: /readyz
+              port: 6443
+            initialDelaySeconds: 5
           env:
             - name: WATCH_NAMESPACE
               value: ""