Skip to content

4. Implement the controller

4.1. Fetch Memcached instance.

  1. Write the following lines in Reconcile function in controllers/memcached_controller.go and import the necessary package.

    import (
    "k8s.io/apimachinery/pkg/api/errors"
    // ...
)

    func (r *MemcachedReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
    log := log.FromContext(ctx)

    // 1. Fetch the Memcached instance
    memcached := &cachev1alpha1.Memcached{}
    err := r.Get(ctx, req.NamespacedName, memcached)
    if err != nil {
        if errors.IsNotFound(err) {
            log.Info("1. Fetch the Memcached instance. Memcached resource not found. Ignoring since object must be deleted")
            return ctrl.Result{}, nil
        }
        // Error reading the object - requeue the request.
        log.Error(err, "1. Fetch the Memcached instance. Failed to get Mmecached")
        return ctrl.Result{}, err
    }
    log.Info("1. Fetch the Memcached instance. Memchached resource found", "memcached.Name", memcached.Name, "memcached.Namespace", memcached.Namespace)
    return ctrl.Result{}, nil
}

  2. Check

    1. Run the controller. 
      make run # if you haven't installed the CRD, you need to run `make install` before running `make run`
    2. Apply a Memcached (CR). 
      kubectl apply -f config/samples/cache_v1alpha1_memcached.yaml

    3. Check logs.

      1.651712191392899e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}

    4. Delete the CR. 

      kubectl delete -f config/samples/cache_v1alpha1_memcached.yaml

    5. Check logs. 

      1.6517122291298392e+09  INFO    controller.memcached    1. Fetch the Memcached instance. Memcached resource not found. Ignoring since object must be deleted    {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default"}

    6. Stop the controller. ctrl-c

4.2 Check if the deployment already exists, and create one if not exists.

  1. Add necessary packages to import. 

    import (
    ...
    "k8s.io/apimachinery/pkg/types"
    ...

    appsv1 "k8s.io/api/apps/v1"
    corev1 "k8s.io/api/core/v1"
    metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

    ...
)

  2. Add the following logics to Reconcile function.

    // 2. Check if the deployment already exists, if not create a new one
found := &appsv1.Deployment{}
err = r.Get(ctx, types.NamespacedName{Name: memcached.Name, Namespace: memcached.Namespace}, found)
if err != nil && errors.IsNotFound(err) {
        // Define a new deployment
        dep := r.deploymentForMemcached(memcached)
        log.Info("2. Check if the deployment already exists, if not create a new one. Creating a new Deployment", "Deployment.Namespace", dep.Namespace, "Deployment.Name", dep.Name)
        err = r.Create(ctx, dep)
        if err != nil {
                log.Error(err, "2. Check if the deployment already exists, if not create a new one. Failed to create new Deployment", "Deployment.Namespace", dep.Namespace, "Deployment.Name", dep.Name)
                return ctrl.Result{}, err
        }
        // Deployment created successfully - return and requeue
        return ctrl.Result{Requeue: true}, nil
} else if err != nil {
        log.Error(err, "2. Check if the deployment already exists, if not create a new one. Failed to get Deployment")
        return ctrl.Result{}, err
}

  3. Create deploymentForMemcached and labelsForMemcached functions.

    1. Initialize appv1.Deployment
    2. Set the replica size to m.Spec.Size (from Memcached custom resource)
    3. Set owner references ctrl.SetControllerReference(m, dep, r.Scheme)

    deploymentForMemcached

    // deploymentForMemcached returns a memcached Deployment object
func (r *MemcachedReconciler) deploymentForMemcached(m *cachev1alpha1.Memcached) *appsv1.Deployment {
    ls := labelsForMemcached(m.Name)
    replicas := m.Spec.Size

    dep := &appsv1.Deployment{
            ObjectMeta: metav1.ObjectMeta{
                    Name:      m.Name,
                    Namespace: m.Namespace,
            },
            Spec: appsv1.DeploymentSpec{
                    Replicas: &replicas,
                    Selector: &metav1.LabelSelector{
                            MatchLabels: ls,
                    },
                    Template: corev1.PodTemplateSpec{
                            ObjectMeta: metav1.ObjectMeta{
                                    Labels: ls,
                            },
                            Spec: corev1.PodSpec{
                                    Containers: []corev1.Container{{
                                            Image:   "memcached:1.4.36-alpine",
                                            Name:    "memcached",
                                            Command: []string{"memcached", "-m=64", "-o", "modern", "-v"},
                                            Ports: []corev1.ContainerPort{{
                                                    ContainerPort: 11211,
                                                    Name:          "memcached",
                                            }},
                                    }},
                            },
                    },
            },
    }
    // Set Memcached instance as the owner and controller
    ctrl.SetControllerReference(m, dep, r.Scheme)
    return dep
}

    labelsForMemcached

    // labelsForMemcached returns the labels for selecting the resources
// belonging to the given memcached CR name.
func labelsForMemcached(name string) map[string]string {
    return map[string]string{"app": "memcached", "memcached_cr": name}
}

  4. Add necessary RBAC to the reconciler.

    //+kubebuilder:rbac:groups=cache.example.com,resources=memcacheds,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=cache.example.com,resources=memcacheds/status,verbs=get;update;patch
//+kubebuilder:rbac:groups=cache.example.com,resources=memcacheds/finalizers,verbs=update
+ //+kubebuilder:rbac:groups=apps,resources=deployments,verbs=get;list;watch;create;update;patch;delete

func (r *MemcachedReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
    // ...
}

    Run make manifests to update config/rbac/role.yaml.

    diff

    --- a/config/rbac/role.yaml
+++ b/config/rbac/role.yaml
@@ -5,6 +5,18 @@ metadata:
   creationTimestamp: null
   name: manager-role
 rules:
+- apiGroups:
+  - apps
+  resources:
+  - deployments
+  verbs:
+  - create
+  - delete
+  - get
+  - list
+  - patch
+  - update
+  - watch

  5. Add Owns(&appsv1.Deployment{}) to the controller manager.

     // SetupWithManager sets up the controller with the Manager.
 func (r *MemcachedReconciler) SetupWithManager(mgr ctrl.Manager) error {
     return ctrl.NewControllerManagedBy(mgr).
         For(&cachev1alpha1.Memcached{}).
+        Owns(&appsv1.Deployment{}). // To capture changes of the Deployments owned by this controller
         Complete(r)
 }
    • For specifies the first resource to watch.
    • Owns specifies the secondary resource to watch. Only capture changes of the Deployments owned by this controller.

  6. Check

    1. Run the controller. 
      make run
    2. Apply a Memcached (CR). 
      kubectl apply -f config/samples/cache_v1alpha1_memcached.yaml

    3. Check logs.

      1.651716003245384e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651716003245449e+09   INFO    controller.memcached    2. Check if the deployment already exists, if not create a new one. Creating a new Deployment   {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "Deployment.Namespace": "default", "Deployment.Name": "memcached-sample"}
1.651716003421142e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651716003426686e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.65171600352492e+09    INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651716004351556e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.6517160069085371e+09  INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651716020319972e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651716021237856e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651716025396706e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}

      There are 10 lines of logs: 1. When Memcached object is created. 1. Create Deployment. 1. Requeued event 1. Deployment creation event and more events are created accordingly. (Owns)

    4. Check Deployment.

      kubectl get deploy memcached-sample
NAME               READY   UP-TO-DATE   AVAILABLE   AGE
memcached-sample   3/3     3            3           19s

    5. Delete the CR. 

      kubectl delete -f config/samples/cache_v1alpha1_memcached.yaml

    6. Check logs. 

      1.651716313736277e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memcached resource not found. Ignoring since object must be deleted    {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default"}
1.65171631389033e+09    INFO    controller.memcached    1. Fetch the Memcached instance. Memcached resource not found. Ignoring since object must be deleted    {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default"}

    7. Check Deployment. 
      kubectl get deploy
No resources found in default namespace.
    8. Stop the controller. ctrl-c

4.3 Ensure the deployment size is the same as the spec.

  1. Add the following lines to Reconcile function.

    // 3. Ensure the deployment size is the same as the spec
size := memcached.Spec.Size
if *found.Spec.Replicas != size {
        found.Spec.Replicas = &size
        err = r.Update(ctx, found)
        if err != nil {
                log.Error(err, "3. Ensure the deployment size is the same as the spec. Failed to update Deployment", "Deployment.Namespace", found.Namespace, "Deployment.Name", found.Name)
                return ctrl.Result{}, err
        }
        // Spec updated - return and requeue
        log.Info("3. Ensure the deployment size is the same as the spec. Update deployment size", "Deployment.Spec.Replicas", size)
        return ctrl.Result{Requeue: true}, nil
}

  2. Check

    1. Run the controller. 

      make run

    2. Apply a Memcached (CR). 

      kubectl apply -f config/samples/cache_v1alpha1_memcached.yaml

    3. Check Deployment.

      kubectl get deploy memcached-sample
NAME               READY   UP-TO-DATE   AVAILABLE   AGE
memcached-sample   3/3     3            3           19s

    4. Change the size to 2 in config/samples/cache_v1alpha1_memcached.yaml

      kubectl apply -f config/samples/cache_v1alpha1_memcached.yaml

    5. Check logs.

      1.6517166666855512e+09  INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651716666815873e+09   INFO    controller.memcached    3. Ensure the deployment size is the same as the spec. Update deployment size   {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "Deployment.Spec.Replicas": 2}
1.651716666815955e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651716666821547e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.65171666694696e+09    INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.65171666713287e+09    INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}

    6. Check Deployment.

      kubectl get deploy
NAME               READY   UP-TO-DATE   AVAILABLE   AGE
memcached-sample   2/2     2            2           115s

    7. Delete the CR. 

      kubectl delete -f config/samples/cache_v1alpha1_memcached.yaml

    8. Check logs. 

      1.65171673062515e+09    INFO    controller.memcached    1. Fetch the Memcached instance. Memcached resource not found. Ignoring since object must be deleted    {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default"}
1.65171673093264e+09    INFO    controller.memcached    1. Fetch the Memcached instance. Memcached resource not found. Ignoring since object must be deleted    {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default"}

    9. Check Deployment. 
      kubectl get deploy
No resources found in default namespace.
    10. Stop the controller. ctrl-c

4.4 Update the Memcached status with the pod names.

  1. Add "reflect" to import. 

    import (
    "reflect"
    // ...
)

  2. Add the following logic to Reconcile functioin.

    // 4. Update the Memcached status with the pod names
// List the pods for this memcached's deployment
podList := &corev1.PodList{}
listOpts := []client.ListOption{
        client.InNamespace(memcached.Namespace),
        client.MatchingLabels(labelsForMemcached(memcached.Name)),
}
if err = r.List(ctx, podList, listOpts...); err != nil {
        log.Error(err, "4. Update the Memcached status with the pod names. Failed to list pods", "Memcached.Namespace", memcached.Namespace, "Memcached.Name", memcached.Name)
        return ctrl.Result{}, err
}
podNames := getPodNames(podList.Items)
log.Info("4. Update the Memcached status with the pod names. Pod list", "podNames", podNames)
// Update status.Nodes if needed
if !reflect.DeepEqual(podNames, memcached.Status.Nodes) {
        memcached.Status.Nodes = podNames
        err := r.Status().Update(ctx, memcached)
        if err != nil {
                log.Error(err, "4. Update the Memcached status with the pod names. Failed to update Memcached status")
                return ctrl.Result{}, err
        }
}
log.Info("4. Update the Memcached status with the pod names. Update memcached.Status", "memcached.Status.Nodes", memcached.Status.Nodes)

  3. Add getPodNames function.

    // getPodNames returns the pod names of the array of pods passed in
func getPodNames(pods []corev1.Pod) []string {
    var podNames []string
    for _, pod := range pods {
            podNames = append(podNames, pod.Name)
    }
    return podNames
}

  4. Add necessary RBAC. 

      //+kubebuilder:rbac:groups=cache.example.com,resources=memcacheds,verbs=get;list;watch;create;update;patch;delete
  //+kubebuilder:rbac:groups=cache.example.com,resources=memcacheds/status,verbs=get;update;patch
  //+kubebuilder:rbac:groups=cache.example.com,resources=memcacheds/finalizers,verbs=update
  //+kubebuilder:rbac:groups=apps,resources=deployments,verbs=get;list;watch;create;update;patch;delete
+ //+kubebuilder:rbac:groups=core,resources=pods,verbs=get;list;

    Run the following command to update config/rbac/role.yaml:

    make manifests

  5. Check

    1. Run the controller. 

      make run

    2. Apply a Memcached (CR). 

      kubectl apply -f config/samples/cache_v1alpha1_memcached.yaml

    3. Check logs.

      1.6517855025391748e+09  INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.6517855025392709e+09  INFO    controller.memcached    2. Check if the deployment already exists, if not create a new one. Creating a new Deployment   {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "Deployment.Namespace": "default", "Deployment.Name": "memcached-sample"}
1.6517855026461499e+09  INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651785502847106e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Pod list     {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "podNames": []}
1.651785502847143e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Update memcached.Status      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Status.Nodes": []}
1.651785502847202e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651785502847241e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Pod list     {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "podNames": []}
1.651785502848351e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Update memcached.Status      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Status.Nodes": []}
1.651785502891124e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.6517855028911989e+09  INFO    controller.memcached    4. Update the Memcached status with the pod names. Pod list     {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "podNames": []}
1.651785502891249e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Update memcached.Status      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Status.Nodes": []}
1.651785502954266e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.6517855029543822e+09  INFO    controller.memcached    4. Update the Memcached status with the pod names. Pod list     {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "podNames": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}
1.651785503020395e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Update memcached.Status      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Status.Nodes": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}
1.6517855030236201e+09  INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651785503023705e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Pod list     {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "podNames": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}
1.6517855030237281e+09  INFO    controller.memcached    4. Update the Memcached status with the pod names. Update memcached.Status      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Status.Nodes": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}
1.6517855031085582e+09  INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651785503108638e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Pod list     {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "podNames": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}
1.651785503108653e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Update memcached.Status      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Status.Nodes": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}
1.65178550697348e+09    INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651785506973621e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Pod list     {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "podNames": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}
1.6517855069736378e+09  INFO    controller.memcached    4. Update the Memcached status with the pod names. Update memcached.Status      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Status.Nodes": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}
1.651785507024296e+09   INFO    controller.memcached    1. Fetch the Memcached instance. Memchached resource found      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Name": "memcached-sample", "memcached.Namespace": "default"}
1.651785507024448e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Pod list     {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "podNames": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}
1.651785507024466e+09   INFO    controller.memcached    4. Update the Memcached status with the pod names. Update memcached.Status      {"reconciler group": "cache.example.com", "reconciler kind": "Memcached", "name": "memcached-sample", "namespace": "default", "memcached.Status.Nodes": ["memcached-sample-5c8cffd96c-wjqsd", "memcached-sample-5c8cffd96c-5pthm"]}

    4. Check Deployment.

      kubectl get deploy
NAME               READY   UP-TO-DATE   AVAILABLE   AGE
memcached-sample   2/2     2            2           115s

    5. Check status in Memcached object.

      kubectl get Memcached memcached-sample -o jsonpath='{.status}' | jq
{
  "nodes": [
    "memcached-sample-6c765df685-9drvp",
    "memcached-sample-6c765df685-g7nl8"
  ]
}

    6. Delete the CR. 

      kubectl delete -f config/samples/cache_v1alpha1_memcached.yaml

    7. Stop the controller. ctrl-c