chore(controllers) remove Ingress API selection

Remove Ingress API selection in favor of simply honoring the CLI disable
flag.

Support for Ingress versions other than networking/v1 was removed in
#3867. The API
selection code was only selecting between networking/v1 and nothing.
Future Kubernetes versions are not expected to abruptly remove the older
API versions if they introduce new Ingress versions, so this selection
code should not be necessary in the future.

internal/manager/controllerdef.go

@@ -2,7 +2,6 @@ package manager
 
 import (
 	"context"
-	"fmt"
 	"reflect"
 
 	"k8s.io/apimachinery/pkg/runtime/schema"
@@ -68,14 +67,6 @@ func setupControllers(
 	kongAdminAPIEndpointsNotifier configuration.EndpointsNotifier,
 	adminAPIsDiscoverer configuration.AdminAPIsDiscoverer,
 ) ([]ControllerDef, error) {
-	restMapper := mgr.GetClient().RESTMapper()
-
-	// Choose the best API version of Ingress to inform which ingress controller to enable.
-	ingressConditions, err := NewIngressControllersConditions(c, restMapper)
-	if err != nil {
-		return nil, fmt.Errorf("ingress version picker failed: %w", err)
-	}
-
 	referenceIndexers := ctrlref.NewCacheIndexers()
 
 	controllers := []ControllerDef{
@@ -97,7 +88,7 @@ func setupControllers(
 		// Core API Controllers
 		// ---------------------------------------------------------------------------
 		{
-			Enabled: ingressConditions.IngressClassNetV1Enabled(),
+			Enabled: c.IngressClassNetV1Enabled,
 			Controller: &configuration.NetV1IngressClassReconciler{
 				Client:           mgr.GetClient(),
 				Log:              ctrl.LoggerFrom(ctx).WithName("controllers").WithName("IngressClass").WithName("netv1"),
@@ -107,7 +98,7 @@ func setupControllers(
 			},
 		},
 		{
-			Enabled: ingressConditions.IngressNetV1Enabled(),
+			Enabled: c.IngressNetV1Enabled,
 			Controller: &configuration.NetV1IngressReconciler{
 				Client:                     mgr.GetClient(),
 				Log:                        ctrl.LoggerFrom(ctx).WithName("controllers").WithName("Ingress").WithName("netv1"),