feature: add load balancer name to IngressClassParams (#4290)

* chore: fix prefixlistsids typo in readme

* feat: add loadBalancerName to IngressClassParams

* feat: add loadBalancerName to IngressClassParams

Author: 1ms-ms

apis/elbv2/v1beta1/ingressclassparams_types.go

@@ -117,6 +117,10 @@ type IPAMConfiguration struct {
 // IngressClassParamsSpec defines the desired state of IngressClassParams
 // +kubebuilder:validation:XValidation:rule="!(has(self.prefixListsIDs) && has(self.PrefixListsIDs))", message="cannot specify both 'prefixListsIDs' and 'PrefixListsIDs' fields"
 type IngressClassParamsSpec struct {
+	// LoadBalancerName defines the name of the load balancer that will be created with this IngressClassParams.
+	// +optional
+	LoadBalancerName string `json:"loadBalancerName,omitempty"`
+
 	// CertificateArn specifies the ARN of the certificates for all Ingresses that belong to IngressClass with this IngressClassParams.
 	// +optional
 	CertificateArn []string `json:"certificateArn,omitempty"`

config/crd/bases/elbv2.k8s.aws_ingressclassparams.yaml

@@ -149,6 +149,10 @@ spec:
                   - value
                   type: object
                 type: array
+              loadBalancerName:
+                description: LoadBalancerName defines the name of the load balancer
+                  that will be created with this IngressClassParams.
+                type: string
               minimumLoadBalancerCapacity:
                 description: MinimumLoadBalancerCapacity define the capacity reservation
                   for LoadBalancers for all Ingress that belong to IngressClass with

docs/guide/ingress/ingress_class.md

@@ -76,6 +76,15 @@ You can use IngressClassParams to enforce settings for a set of Ingresses.
       - key: org
         value: my-org
     ```
+    - with loadBalancerName
+    ```
+    apiVersion: elbv2.k8s.aws/v1beta1
+    kind: IngressClassParams
+    metadata:
+      name: awesome-class
+    spec:
+      loadBalancerName: name-1
+    ```
     - with namespaceSelector
     ```
     apiVersion: elbv2.k8s.aws/v1beta1
@@ -214,6 +223,14 @@ You can use IngressClassParams to enforce settings for a set of Ingresses.
 
 ### IngressClassParams specification
 
+#### spec.loadBalancerName
+`loadBalancerName` is an optional setting.
+
+Cluster administrators can use the `loadBalancerName` field to specify name of the load balancer that will be provisioned by the controller.
+
+1. If `loadBalancerName` is set, one load balancer per `IngressClass` will be provisioned. LBC will ignore the `alb.ingress.kubernetes.io/load-balancer-name` annotation.
+2. If `loadBalancerName` is not set, Ingresses with this IngressClass can continue to use `alb.ingress.kubernetes.io/load-balancer-name annotation` to specify name of the load balancer.
+
 #### spec.namespaceSelector
 `namespaceSelector` is an optional setting that follows general Kubernetes
 [label selector](https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#label-selectors)

helm/aws-load-balancer-controller/crds/crds.yaml

@@ -148,6 +148,10 @@ spec:
                   - value
                   type: object
                 type: array
+              loadBalancerName:
+                description: LoadBalancerName defines the name of the load balancer
+                  that will be created with this IngressClassParams.
+                type: string
               minimumLoadBalancerCapacity:
                 description: MinimumLoadBalancerCapacity define the capacity reservation
                   for LoadBalancers for all Ingress that belong to IngressClass with

pkg/ingress/model_build_load_balancer.go

@@ -99,6 +99,11 @@ var invalidLoadBalancerNamePattern = regexp.MustCompile("[[:^alnum:]]")
 func (t *defaultModelBuildTask) buildLoadBalancerName(_ context.Context, scheme elbv2model.LoadBalancerScheme) (string, error) {
 	explicitNames := sets.String{}
 	for _, member := range t.ingGroup.Members {
+		if member.IngClassConfig.IngClassParams != nil && member.IngClassConfig.IngClassParams.Spec.LoadBalancerName != "" {
+			loadBalancerName := member.IngClassConfig.IngClassParams.Spec.LoadBalancerName
+			explicitNames.Insert(loadBalancerName)
+			continue
+		}
 		rawName := ""
 		if exists := t.annotationParser.ParseStringAnnotation(annotations.IngressSuffixLoadBalancerName, &rawName, member.Ing.Annotations); !exists {
 			continue

pkg/ingress/model_build_load_balancer_test.go

@@ -573,6 +573,35 @@ func Test_defaultModelBuildTask_buildLoadBalancerName(t *testing.T) {
 			},
 			want: "foo",
 		},
+		{
+			name: "name IngressClassParams",
+			fields: fields{
+				ingGroup: Group{
+					ID: GroupID{Namespace: "awesome-ns", Name: "ing-1"},
+					Members: []ClassifiedIngress{
+						{
+							Ing: &networking.Ingress{
+								ObjectMeta: metav1.ObjectMeta{
+									Namespace: "awesome-ns",
+									Name:      "ing-1",
+									Annotations: map[string]string{
+										"alb.ingress.kubernetes.io/load-balancer-name": "name-2",
+									},
+								},
+							},
+							IngClassConfig: ClassConfiguration{
+								IngClassParams: &v1beta1.IngressClassParams{
+									Spec: v1beta1.IngressClassParamsSpec{
+										LoadBalancerName: "name-1",
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			want: "name-1",
+		},
 		{
 			name: "trim name annotation",
 			fields: fields{