Improve and Simplify the Getting Started Guide

- Refined the sample code implementation to keep it minimal, helping users better understand the core concepts.
- Streamlined the guide by focusing on the main information and removing extraneous details.
- Ensured that the code and samples in the guide are consistent with the generated project.
- Simplified navigation by hiding the full code, making it easier for users to follow along.
- Replaced the use of the deploy image plugin with direct commands to provide more comprehensive and straightforward information.

Author: camilamacedo86

docs/book/src/getting-started.md

@@ -13,6 +13,7 @@ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */
+// +kubebuilder:docs-gen:collapse=Apache License
 
 package v1alpha1
 
@@ -23,6 +24,8 @@ import (
 // EDIT THIS FILE!  THIS IS SCAFFOLDING FOR YOU TO OWN!
 // NOTE: json tags are required.  Any new fields you add must have json tags for the fields to be serialized.
 
+// +kubebuilder:docs-gen:collapse=Imports
+
 // MemcachedSpec defines the desired state of Memcached
 type MemcachedSpec struct {
 	// INSERT ADDITIONAL SPEC FIELDS - desired state of cluster
@@ -35,9 +38,6 @@ type MemcachedSpec struct {
 	// +kubebuilder:validation:Maximum=3
 	// +kubebuilder:validation:ExclusiveMaximum=false
 	Size int32 `json:"size,omitempty"`
-
-	// Port defines the port that will be used to init the container with the image
-	ContainerPort int32 `json:"containerPort,omitempty"`
 }
 
 // MemcachedStatus defines the observed state of Memcached

docs/book/src/getting-started/testdata/project/api/v1alpha1/memcached_types.go

@@ -39,11 +39,6 @@ spec:
           spec:
             description: MemcachedSpec defines the desired state of Memcached
             properties:
-              containerPort:
-                description: Port defines the port that will be used to init the container
-                  with the image
-                format: int32
-                type: integer
               size:
                 description: |-
                   Size defines the number of Memcached instances

docs/book/src/getting-started/testdata/project/config/crd/bases/cache.example.com_memcacheds.yaml

@@ -7,5 +7,3 @@ spec:
   # of Pods/Instances your Operand must have on cluster
   size: 1
 
-  # TODO(user): edit the following value to ensure the container has the right port to be initialized
-  containerPort: 11211

docs/book/src/getting-started/testdata/project/config/samples/cache_v1alpha1_memcached.yaml

@@ -19,8 +19,7 @@ package controller
 import (
 	"context"
 	"fmt"
-	"os"
-	"strings"
+
 	"time"
 
 	appsv1 "k8s.io/api/apps/v1"
@@ -33,14 +32,12 @@ import (
 	"k8s.io/client-go/tools/record"
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
-	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
+
 	"sigs.k8s.io/controller-runtime/pkg/log"
 
 	cachev1alpha1 "example.com/memcached/api/v1alpha1"
 )
 
-const memcachedFinalizer = "cache.example.com/finalizer"
-
 // Definitions to manage status conditions
 const (
 	// typeAvailableMemcached represents the status of the Deployment reconciliation
@@ -117,79 +114,6 @@ func (r *MemcachedReconciler) Reconcile(ctx context.Context, req ctrl.Request) (
 		}
 	}
 
-	// Let's add a finalizer. Then, we can define some operations which should
-	// occur before the custom resource is deleted.
-	// More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/finalizers
-	if !controllerutil.ContainsFinalizer(memcached, memcachedFinalizer) {
-		log.Info("Adding Finalizer for Memcached")
-		if ok := controllerutil.AddFinalizer(memcached, memcachedFinalizer); !ok {
-			log.Error(err, "Failed to add finalizer into the custom resource")
-			return ctrl.Result{Requeue: true}, nil
-		}
-
-		if err = r.Update(ctx, memcached); err != nil {
-			log.Error(err, "Failed to update custom resource to add finalizer")
-			return ctrl.Result{}, err
-		}
-	}
-
-	// Check if the Memcached instance is marked to be deleted, which is
-	// indicated by the deletion timestamp being set.
-	isMemcachedMarkedToBeDeleted := memcached.GetDeletionTimestamp() != nil
-	if isMemcachedMarkedToBeDeleted {
-		if controllerutil.ContainsFinalizer(memcached, memcachedFinalizer) {
-			log.Info("Performing Finalizer Operations for Memcached before delete CR")
-
-			// Let's add here a status "Downgrade" to reflect that this resource began its process to be terminated.
-			meta.SetStatusCondition(&memcached.Status.Conditions, metav1.Condition{Type: typeDegradedMemcached,
-				Status: metav1.ConditionUnknown, Reason: "Finalizing",
-				Message: fmt.Sprintf("Performing finalizer operations for the custom resource: %s ", memcached.Name)})
-
-			if err := r.Status().Update(ctx, memcached); err != nil {
-				log.Error(err, "Failed to update Memcached status")
-				return ctrl.Result{}, err
-			}
-
-			// Perform all operations required before removing the finalizer and allow
-			// the Kubernetes API to remove the custom resource.
-			r.doFinalizerOperationsForMemcached(memcached)
-
-			// TODO(user): If you add operations to the doFinalizerOperationsForMemcached method
-			// then you need to ensure that all worked fine before deleting and updating the Downgrade status
-			// otherwise, you should requeue here.
-
-			// Re-fetch the memcached Custom Resource before updating the status
-			// so that we have the latest state of the resource on the cluster and we will avoid
-			// raising the error "the object has been modified, please apply
-			// your changes to the latest version and try again" which would re-trigger the reconciliation
-			if err := r.Get(ctx, req.NamespacedName, memcached); err != nil {
-				log.Error(err, "Failed to re-fetch memcached")
-				return ctrl.Result{}, err
-			}
-
-			meta.SetStatusCondition(&memcached.Status.Conditions, metav1.Condition{Type: typeDegradedMemcached,
-				Status: metav1.ConditionTrue, Reason: "Finalizing",
-				Message: fmt.Sprintf("Finalizer operations for custom resource %s name were successfully accomplished", memcached.Name)})
-
-			if err := r.Status().Update(ctx, memcached); err != nil {
-				log.Error(err, "Failed to update Memcached status")
-				return ctrl.Result{}, err
-			}
-
-			log.Info("Removing Finalizer for Memcached after successfully perform the operations")
-			if ok := controllerutil.RemoveFinalizer(memcached, memcachedFinalizer); !ok {
-				log.Error(err, "Failed to remove finalizer for Memcached")
-				return ctrl.Result{Requeue: true}, nil
-			}
-
-			if err := r.Update(ctx, memcached); err != nil {
-				log.Error(err, "Failed to remove finalizer for Memcached")
-				return ctrl.Result{}, err
-			}
-		}
-		return ctrl.Result{}, nil
-	}
-
 	// 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)
@@ -282,37 +206,12 @@ func (r *MemcachedReconciler) Reconcile(ctx context.Context, req ctrl.Request) (
 	return ctrl.Result{}, nil
 }
 
-// finalizeMemcached will perform the required operations before delete the CR.
-func (r *MemcachedReconciler) doFinalizerOperationsForMemcached(cr *cachev1alpha1.Memcached) {
-	// TODO(user): Add the cleanup steps that the operator
-	// needs to do before the CR can be deleted. Examples
-	// of finalizers include performing backups and deleting
-	// resources that are not owned by this CR, like a PVC.
-
-	// Note: It is not recommended to use finalizers with the purpose of deleting resources which are
-	// created and managed in the reconciliation. These ones, such as the Deployment created on this reconcile,
-	// are defined as dependent of the custom resource. See that we use the method ctrl.SetControllerReference.
-	// to set the ownerRef which means that the Deployment will be deleted by the Kubernetes API.
-	// More info: https://kubernetes.io/docs/tasks/administer-cluster/use-cascading-deletion/
-
-	// The following implementation will raise an event
-	r.Recorder.Event(cr, "Warning", "Deleting",
-		fmt.Sprintf("Custom Resource %s is being deleted from the namespace %s",
-			cr.Name,
-			cr.Namespace))
-}
-
 // deploymentForMemcached returns a Memcached Deployment object
 func (r *MemcachedReconciler) deploymentForMemcached(
 	memcached *cachev1alpha1.Memcached) (*appsv1.Deployment, error) {
-	ls := labelsForMemcached(memcached.Name)
-	replicas := memcached.Spec.Size
 
-	// Get the Operand image
-	image, err := imageForMemcached()
-	if err != nil {
-		return nil, err
-	}
+	replicas := memcached.Spec.Size
+	image := "memcached:1.6.26-alpine3.19"
 
 	dep := &appsv1.Deployment{
 		ObjectMeta: metav1.ObjectMeta{
@@ -321,42 +220,9 @@ func (r *MemcachedReconciler) deploymentForMemcached(
 		},
 		Spec: appsv1.DeploymentSpec{
 			Replicas: &replicas,
-			Selector: &metav1.LabelSelector{
-				MatchLabels: ls,
-			},
 			Template: corev1.PodTemplateSpec{
-				ObjectMeta: metav1.ObjectMeta{
-					Labels: ls,
-				},
 				Spec: corev1.PodSpec{
-					// TODO(user): Uncomment the following code to configure the nodeAffinity expression
-					// according to the platforms which are supported by your solution. It is considered
-					// best practice to support multiple architectures. build your manager image using the
-					// makefile target docker-buildx. Also, you can use docker manifest inspect <image>
-					// to check what are the platforms supported.
-					// More info: https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/#node-affinity
-					//Affinity: &corev1.Affinity{
-					//	NodeAffinity: &corev1.NodeAffinity{
-					//		RequiredDuringSchedulingIgnoredDuringExecution: &corev1.NodeSelector{
-					//			NodeSelectorTerms: []corev1.NodeSelectorTerm{
-					//				{
-					//					MatchExpressions: []corev1.NodeSelectorRequirement{
-					//						{
-					//							Key:      "kubernetes.io/arch",
-					//							Operator: "In",
-					//							Values:   []string{"amd64", "arm64", "ppc64le", "s390x"},
-					//						},
-					//						{
-					//							Key:      "kubernetes.io/os",
-					//							Operator: "In",
-					//							Values:   []string{"linux"},
-					//						},
-					//					},
-					//				},
-					//			},
-					//		},
-					//	},
-					//},
+
 					SecurityContext: &corev1.PodSecurityContext{
 						RunAsNonRoot: &[]bool{true}[0],
 						// IMPORTANT: seccomProfile was introduced with Kubernetes 1.19
@@ -383,7 +249,7 @@ func (r *MemcachedReconciler) deploymentForMemcached(
 							},
 						},
 						Ports: []corev1.ContainerPort{{
-							ContainerPort: memcached.Spec.ContainerPort,
+							ContainerPort: 11211,
 							Name:          "memcached",
 						}},
 						Command: []string{"memcached", "-m=64", "-o", "modern", "-v"},
@@ -401,31 +267,6 @@ func (r *MemcachedReconciler) deploymentForMemcached(
 	return dep, nil
 }
 
-// labelsForMemcached returns the labels for selecting the resources
-// More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/common-labels/
-func labelsForMemcached(name string) map[string]string {
-	var imageTag string
-	image, err := imageForMemcached()
-	if err == nil {
-		imageTag = strings.Split(image, ":")[1]
-	}
-	return map[string]string{"app.kubernetes.io/name": "project",
-		"app.kubernetes.io/version":    imageTag,
-		"app.kubernetes.io/managed-by": "MemcachedController",
-	}
-}
-
-// imageForMemcached gets the Operand image which is managed by this controller
-// from the MEMCACHED_IMAGE environment variable defined in the config/manager/manager.yaml
-func imageForMemcached() (string, error) {
-	var imageEnvVar = "MEMCACHED_IMAGE"
-	image, found := os.LookupEnv(imageEnvVar)
-	if !found {
-		return "", fmt.Errorf("Unable to find %s environment variable with the image", imageEnvVar)
-	}
-	return image, nil
-}
-
 // SetupWithManager sets up the controller with the Manager.
 // Note that the Deployment will be also watched in order to ensure its
 // desirable state on the cluster

docs/book/src/getting-started/testdata/project/internal/controller/memcached_controller.go

@@ -75,8 +75,7 @@ var _ = Describe("Memcached controller", func() {
 						Namespace: namespace.Name,
 					},
 					Spec: cachev1alpha1.MemcachedSpec{
-						Size:          1,
-						ContainerPort: 11211,
+						Size: 1,
 					},
 				}