func (f *sharedInformerFactory) ForResource(resource schema.GroupVersionResource) (GenericInformer, error) {
	switch resource {
	case v1alpha1.SchemeGroupVersion.WithResource("iamidentitymappings"):
		return &genericInformer{resource: resource.GroupResource(), informer: f.Iamauthenticator().V1alpha1().IAMIdentityMappings().Informer()}, nil
	}
	return nil, fmt.Errorf("no informer found for %v", resource)
}
ForResource gives generic access to a shared informer of the matching type
TODO extend this to unknown resources with a client pool
package externalversions
import (
	"fmt"
	schema "k8s.io/apimachinery/pkg/runtime/schema"
	cache "k8s.io/client-go/tools/cache"
	v1alpha1 "sigs.k8s.io/aws-iam-authenticator/pkg/mapper/crd/apis/iamauthenticator/v1alpha1"
)
type GenericInformer interface {
	Informer() cache.SharedIndexInformer
	Lister() cache.GenericLister
}
type genericInformer struct {
	informer cache.SharedIndexInformer
	resource schema.GroupResource
}
func (f *genericInformer) Informer() cache.SharedIndexInformer {
	return f.informer
}
func (f *genericInformer) Lister() cache.GenericLister {
	return cache.NewGenericLister(f.Informer().GetIndexer(), f.resource)
}