feat: support disabling generated IPAddressPool

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## v0.40.0
+
+- Metallb addon now has a builder. The builder can disable IPAddressPool
+  creation.
+  [#835](https://github.com/Kong/kubernetes-testing-framework/pull/835)
+
 ## v0.39.1
 
 - Removed a module exclude that made `go install` unhappy.

pkg/clusters/addons/metallb/metallb.go

@@ -58,7 +58,9 @@ var (
 	}
 )
 
-type addon struct{}
+type addon struct {
+	disablePoolCreation bool
+}
 
 func New() clusters.Addon {
 	return &addon{}
@@ -81,7 +83,7 @@ func (a *addon) Deploy(ctx context.Context, cluster clusters.Cluster) error {
 		return fmt.Errorf("the metallb addon is currently only supported on %s clusters", kind.KindClusterType)
 	}
 
-	return deployMetallbForKindCluster(ctx, cluster, kind.DefaultKindDockerNetwork)
+	return a.deployMetallbForKindCluster(ctx, cluster, kind.DefaultKindDockerNetwork)
 }
 
 func (a *addon) Delete(ctx context.Context, cluster clusters.Cluster) error {
@@ -151,7 +153,7 @@ var (
 // -----------------------------------------------------------------------------
 
 // deployMetallbForKindCluster deploys Metallb to the given Kind cluster using the Docker network provided for LoadBalancer IPs.
-func deployMetallbForKindCluster(ctx context.Context, cluster clusters.Cluster, dockerNetwork string) error {
+func (a *addon) deployMetallbForKindCluster(ctx context.Context, cluster clusters.Cluster, dockerNetwork string) error {
 	// ensure the namespace for metallb is created
 	ns := corev1.Namespace{ObjectMeta: metav1.ObjectMeta{Name: DefaultNamespace}}
 	if _, err := cluster.Client().CoreV1().Namespaces().Create(ctx, &ns, metav1.CreateOptions{}); err != nil {
@@ -167,8 +169,10 @@ func deployMetallbForKindCluster(ctx context.Context, cluster clusters.Cluster,
 	}
 
 	// create an ip address pool
-	if err := createIPAddressPool(ctx, cluster, dockerNetwork); err != nil {
-		return err
+	if !a.disablePoolCreation {
+		if err := createIPAddressPool(ctx, cluster, dockerNetwork); err != nil {
+			return err
+		}
 	}
 
 	if err := createL2Advertisement(ctx, cluster); err != nil {
@@ -400,3 +404,33 @@ func metallbDeleteHack(ctx context.Context, kubeconfig *os.File) error {
 		WithStdout(io.Discard).
 		Do(ctx)
 }
+
+// -----------------------------------------------------------------------------
+// Metallb Builder
+// -----------------------------------------------------------------------------
+
+// Builder is a configuration tool for metallb cluster.Addons.
+type Builder struct {
+	disablePoolCreation bool
+}
+
+// NewBuilder provides a new Builder object with default addon settings.
+func NewBuilder() *Builder {
+	builder := &Builder{
+		disablePoolCreation: false,
+	}
+	return builder
+}
+
+// WithPoolDisabled instructs the builder to create addons with pool creation disabled.
+func (b *Builder) WithPoolDisabled() *Builder {
+	b.disablePoolCreation = true
+	return b
+}
+
+// Build generates an addon with the builder's configuration.
+func (b *Builder) Build() *addon {
+	return &addon{
+		disablePoolCreation: b.disablePoolCreation,
+	}
+}