feat: hot reload tls

Author: husnialhamdani

api/rediscluster/v1beta2/rediscluster_types.go

@@ -121,7 +121,8 @@ type RedisClusterStatus struct {
 	// +kubebuilder:default=0
 	ReadyLeaderReplicas int32 `json:"readyLeaderReplicas,omitempty"`
 	// +kubebuilder:default=0
-	ReadyFollowerReplicas int32 `json:"readyFollowerReplicas,omitempty"`
+	ReadyFollowerReplicas int32  `json:"readyFollowerReplicas,omitempty"`
+	TLSLastVersion        string `json:"tlsLastVersion,omitempty"`
 }
 
 type RedisClusterState string

config/crd/bases/redis.redis.opstreelabs.in_redisclusters.yaml

@@ -7858,6 +7858,8 @@ spec:
                 type: string
               state:
                 type: string
+              tlsLastVersion:
+                type: string
             type: object
         required:
         - spec

internal/cmd/manager/cmd.go

@@ -239,12 +239,13 @@ func setupControllers(mgr ctrl.Manager, k8sClient kubernetes.Interface, maxConcu
 		return err
 	}
 	if err := (&redisclustercontroller.Reconciler{
-		Client:      mgr.GetClient(),
-		K8sClient:   k8sClient,
-		Healer:      healer,
-		Checker:     redis.NewChecker(k8sClient),
-		Recorder:    mgr.GetEventRecorderFor("rediscluster-controller"),
-		StatefulSet: k8sutils.NewStatefulSetService(k8sClient),
+		Client:          mgr.GetClient(),
+		K8sClient:       k8sClient,
+		Healer:          healer,
+		Checker:         redis.NewChecker(k8sClient),
+		Recorder:        mgr.GetEventRecorderFor("rediscluster-controller"),
+		StatefulSet:     k8sutils.NewStatefulSetService(k8sClient),
+		ResourceWatcher: intctrlutil.NewResourceWatcher(),
 	}).SetupWithManager(mgr, controller.Options{MaxConcurrentReconciles: maxConcurrentReconciles}); err != nil {
 		setupLog.Error(err, "unable to create controller", "controller", "RedisCluster")
 		return err

internal/controller/rediscluster/rediscluster_controller.go

@@ -19,7 +19,10 @@ package rediscluster
 import (
 	"context"
 	"fmt"
+	"k8s.io/apimachinery/pkg/types"
 	"reflect"
+	"sigs.k8s.io/controller-runtime/pkg/handler"
+	"strconv"
 	"time"
 
 	rcvb2 "github.com/OT-CONTAINER-KIT/redis-operator/api/rediscluster/v1beta2"
@@ -49,10 +52,11 @@ const (
 type Reconciler struct {
 	client.Client
 	k8sutils.StatefulSet
-	Healer    redis.Healer
-	Checker   redis.Checker
-	K8sClient kubernetes.Interface
-	Recorder  record.EventRecorder
+	Healer          redis.Healer
+	Checker         redis.Checker
+	K8sClient       kubernetes.Interface
+	Recorder        record.EventRecorder
+	ResourceWatcher *intctrlutil.ResourceWatcher
 }
 
 func (r *Reconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
@@ -84,6 +88,21 @@ func (r *Reconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Resu
 		return intctrlutil.RequeueE(ctx, err, "failed to add finalizer")
 	}
 
+	// hotreload tls
+	if instance.Spec.TLS != nil {
+		r.ResourceWatcher.Watch(
+			ctx,
+			types.NamespacedName{
+				Namespace: instance.Namespace,
+				Name:      instance.Spec.TLS.Secret.SecretName,
+			},
+			types.NamespacedName{
+				Namespace: instance.Namespace,
+				Name:      instance.Name,
+			},
+		)
+	}
+
 	// Check if the cluster is downscaled
 	if leaderCount := r.GetStatefulSetReplicas(ctx, instance.Namespace, instance.Name+"-leader"); leaderReplicas < leaderCount {
 		if !r.IsStatefulSetReady(ctx, instance.Namespace, instance.Name+"-leader") || !r.IsStatefulSetReady(ctx, instance.Namespace, instance.Name+"-follower") {
@@ -201,6 +220,14 @@ func (r *Reconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Resu
 		return intctrlutil.Reconciled()
 	}
 
+	if instance.Spec.TLS != nil {
+		err := r.reloadTLS(ctx, instance, int(leaderReplicas), int(followerReplicas))
+		if err != nil {
+			log.FromContext(ctx).Error(err, "hotReloadTLS failed, will retry later")
+			return intctrlutil.RequeueAfter(ctx, 30*time.Second, "Retry hotReloadTLS")
+		}
+	}
+
 	// Mark the cluster status as bootstrapping if all the leader and follower nodes are ready
 	if instance.Status.ReadyLeaderReplicas != leaderReplicas || instance.Status.ReadyFollowerReplicas != followerReplicas {
 		requeue, err := r.updateStatus(ctx, instance, rcvb2.RedisClusterStatus{
@@ -349,6 +376,24 @@ func (r *Reconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Resu
 	return intctrlutil.RequeueAfter(ctx, time.Second*10, "")
 }
 
+func (r *Reconciler) reloadTLS(ctx context.Context, rc *rcvb2.RedisCluster, leaderReplicas, followerReplicas int) error {
+	log.FromContext(ctx).Info("hotReloadTLS: reloading TLS configuration")
+	for i := 0; i < followerReplicas; i++ {
+		err := k8sutils.HotReloadTLS(ctx, r.K8sClient, rc, rc.Name+"-follower-"+strconv.Itoa(i))
+		if err != nil {
+			return fmt.Errorf("RedisCluster controller -> failed reloading tls in follower: %w", err)
+		}
+	}
+	for j := 0; j < leaderReplicas; j++ {
+		err := k8sutils.HotReloadTLS(ctx, r.K8sClient, rc, rc.Name+"-leader-"+strconv.Itoa(j))
+		if err != nil {
+			return fmt.Errorf("RedisCluster controller -> failed reloading tls in leader: %w", err)
+		}
+	}
+	log.FromContext(ctx).Info("hotReloadTLS: reloaded TLS configuration has been completed")
+	return nil
+}
+
 func (r *Reconciler) updateStatus(ctx context.Context, rc *rcvb2.RedisCluster, status rcvb2.RedisClusterStatus) (requeue bool, err error) {
 	if reflect.DeepEqual(rc.Status, status) {
 		return false, nil
@@ -380,5 +425,7 @@ func (r *Reconciler) SetupWithManager(mgr ctrl.Manager, opts controller.Options)
 		For(&rcvb2.RedisCluster{}).
 		Owns(&appsv1.StatefulSet{}).
 		WithOptions(opts).
+		Watches(&rcvb2.RedisCluster{}, &handler.EnqueueRequestForObject{}).
+		Watches(&corev1.Secret{}, r.ResourceWatcher).
 		Complete(r)
 }

internal/k8sutils/redis.go

@@ -289,6 +289,22 @@ func createRedisReplicationCommand(ctx context.Context, client kubernetes.Interf
 	return cmd
 }
 
+func HotReloadTLS(ctx context.Context, client kubernetes.Interface, cr *rcvb2.RedisCluster, podName string) error {
+	redisClient := configureRedisClient(ctx, client, cr, podName)
+	commands := []struct{ k, v string }{
+		{"tls-cert-file", "/tls/tls.crt"},
+		{"tls-key-file", "/tls/tls.key"},
+		{"tls-ca-cert-file", "/tls/ca.crt"},
+	}
+	for _, cmd := range commands {
+		if err := redisClient.ConfigSet(ctx, cmd.k, cmd.v).Err(); err != nil {
+			log.FromContext(ctx).Error(err, "hotReloadTLS: Failed to set tls config", "cmd", cmd, "on pod", podName)
+			return err
+		}
+	}
+	return nil
+}
+
 // ExecuteRedisReplicationCommand will execute the replication command
 func ExecuteRedisReplicationCommand(ctx context.Context, client kubernetes.Interface, cr *rcvb2.RedisCluster) {
 	var podIP string