refactor(policy-server): get rid of useless labels

Use standard naming convention for our labels (use DNS name as part of
key). Also, remove non-standard labels when possible and just use the
common Kubernetes labels we are now using.

Signed-off-by: Flavio Castelli <[email protected]>

Author: flavio

api/policies/v1/policyserver_types.go

@@ -187,10 +187,6 @@ func (ps *PolicyServer) NameWithPrefix() string {
 	return "policy-server-" + ps.Name
 }
 
-func (ps *PolicyServer) AppLabel() string {
-	return "kubewarden-" + ps.NameWithPrefix()
-}
-
 // CommonLabels returns the common labels to be used with the resources
 // associated to a Policy Server. The labels defined follow
 // Kubernetes guidelines: https://kubernetes.io/docs/concepts/overview/working-with-objects/common-labels/#labels

internal/constants/constants.go

@@ -30,10 +30,8 @@ const (
 	PolicyServerVerificationConfigContainerPath = "/verification"
 
 	// Labels.
-	AppLabelKey                     = "app"
-	PolicyServerLabelKey            = "kubewarden/policy-server"
+	PolicyServerLabelKey            = "kubewarden.io/policy-server"
 	ComponentPolicyServerLabelValue = "policy-server"
-	NameLabelKey                    = "app.kubernetes.io/name"
 	InstanceLabelKey                = "app.kubernetes.io/instance"
 	ComponentLabelKey               = "app.kubernetes.io/component"
 	PartOfLabelKey                  = "app.kubernetes.io/part-of"

internal/controller/policyserver_controller_deployment.go

@@ -295,7 +295,6 @@ func configureLabelsAndAnnotations(policyServerDeployment *appsv1.Deployment, po
 	if policyServerDeployment.Labels == nil {
 		policyServerDeployment.Labels = make(map[string]string)
 	}
-	policyServerDeployment.Labels[constants.AppLabelKey] = policyServer.AppLabel()
 	policyServerDeployment.Labels[constants.PolicyServerLabelKey] = policyServer.Name
 
 	for key, value := range policyServer.CommonLabels() {
@@ -378,19 +377,21 @@ func buildPolicyServerDeploymentSpec(
 	podSecurityContext *corev1.PodSecurityContext,
 ) appsv1.DeploymentSpec {
 	templateLabels := map[string]string{
-		constants.AppLabelKey: policyServer.AppLabel(),
 		constants.PolicyServerDeploymentPodSpecConfigVersionLabel: configMapVersion,
 		constants.PolicyServerLabelKey:                            policyServer.Name,
 	}
-	for key, value := range policyServer.CommonLabels() {
+
+	commonLabels := policyServer.CommonLabels()
+	for key, value := range commonLabels {
 		templateLabels[key] = value
 	}
 
 	return appsv1.DeploymentSpec{
 		Replicas: &policyServer.Spec.Replicas,
 		Selector: &metav1.LabelSelector{
 			MatchLabels: map[string]string{
-				constants.AppLabelKey: policyServer.AppLabel(),
+				constants.PartOfLabelKey:   commonLabels[constants.PartOfLabelKey],
+				constants.InstanceLabelKey: commonLabels[constants.InstanceLabelKey],
 			},
 		},
 		Strategy: appsv1.DeploymentStrategy{

internal/controller/policyserver_controller_pdb.go

@@ -37,11 +37,12 @@ func deletePodDisruptionBudget(ctx context.Context, policyServer *policiesv1.Pol
 }
 
 func reconcilePodDisruptionBudget(ctx context.Context, policyServer *policiesv1.PolicyServer, k8s client.Client, namespace string) error {
+	commonLabels := policyServer.CommonLabels()
 	pdb := &k8spoliciesv1.PodDisruptionBudget{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      policyServer.NameWithPrefix(),
 			Namespace: namespace,
-			Labels:    policyServer.CommonLabels(),
+			Labels:    commonLabels,
 		},
 	}
 	_, err := controllerutil.CreateOrPatch(ctx, k8s, pdb, func() error {
@@ -53,7 +54,8 @@ func reconcilePodDisruptionBudget(ctx context.Context, policyServer *policiesv1.
 
 		pdb.Spec.Selector = &metav1.LabelSelector{
 			MatchLabels: map[string]string{
-				constants.AppLabelKey:          policyServer.AppLabel(),
+				constants.InstanceLabelKey:     commonLabels[constants.InstanceLabelKey],
+				constants.PartOfLabelKey:       commonLabels[constants.PartOfLabelKey],
 				constants.PolicyServerLabelKey: policyServer.GetName(),
 			},
 		}

internal/controller/policyserver_controller_service.go

@@ -51,11 +51,12 @@ func (r *PolicyServerReconciler) reconcilePolicyServerService(ctx context.Contex
 }
 
 func (r *PolicyServerReconciler) updateService(svc *corev1.Service, policyServer *policiesv1.PolicyServer) error {
+	commonLabels := policyServer.CommonLabels()
+
 	svc.Name = policyServer.NameWithPrefix()
 	svc.Namespace = r.DeploymentsNamespace
-	svc.Labels = map[string]string{
-		constants.AppLabelKey: policyServer.AppLabel(),
-	}
+	svc.Labels = commonLabels
+
 	svc.Spec = corev1.ServiceSpec{
 		Ports: []corev1.ServicePort{
 			{
@@ -75,7 +76,8 @@ func (r *PolicyServerReconciler) updateService(svc *corev1.Service, policyServer
 			},
 		},
 		Selector: map[string]string{
-			constants.AppLabelKey: policyServer.AppLabel(),
+			constants.InstanceLabelKey: commonLabels[constants.InstanceLabelKey],
+			constants.PartOfLabelKey:   commonLabels[constants.PartOfLabelKey],
 		},
 	}
 	if r.MetricsEnabled {

internal/controller/utils_test.go

@@ -193,7 +193,8 @@ func policyServerPodDisruptionBudgetMatcher(policyServer *policiesv1.PolicyServe
 				"MinAvailable":   minAvailableMatcher,
 				"Selector": PointTo(MatchAllFields(Fields{
 					"MatchLabels": MatchAllKeys(Keys{
-						constants.AppLabelKey:          Equal(policyServer.AppLabel()),
+						constants.InstanceLabelKey:     Equal(policyServer.CommonLabels()[constants.InstanceLabelKey]),
+						constants.PartOfLabelKey:       Equal(policyServer.CommonLabels()[constants.PartOfLabelKey]),
 						constants.PolicyServerLabelKey: Equal(policyServer.GetName()),
 					}),
 					"MatchExpressions": Ignore(),