add.go

// SPDX-FileCopyrightText: SAP SE or an SAP affiliate company and Gardener contributors
//
// SPDX-License-Identifier: Apache-2.0

package migration

import (
	"k8s.io/utils/ptr"
	"sigs.k8s.io/controller-runtime/pkg/builder"
	"sigs.k8s.io/controller-runtime/pkg/controller"
	"sigs.k8s.io/controller-runtime/pkg/event"
	"sigs.k8s.io/controller-runtime/pkg/manager"
	"sigs.k8s.io/controller-runtime/pkg/predicate"

	gardencorev1beta1 "github.com/gardener/gardener/pkg/apis/core/v1beta1"
	v1beta1helper "github.com/gardener/gardener/pkg/apis/core/v1beta1/helper"
)

// ControllerName is the name of this controller.
const ControllerName = "shoot-migration"

// AddToManager adds Reconciler to the given manager.
func (r *Reconciler) AddToManager(mgr manager.Manager) error {
	if r.Client == nil {
		r.Client = mgr.GetClient()
	}

	return builder.
		ControllerManagedBy(mgr).
		Named(ControllerName).
		For(&gardencorev1beta1.Shoot{}, builder.WithPredicates(r.ShootPredicate())).
		WithOptions(controller.Options{
			MaxConcurrentReconciles: ptr.Deref(r.Config.ConcurrentSyncs, 0),
		}).
		Complete(r)
}

// ShootPredicate reacts on Shoot events that indicate that the control plane needs to be prepared for migration.
func (r *Reconciler) ShootPredicate() predicate.Predicate {
	requireConstraintRemoval := func(shoot *gardencorev1beta1.Shoot) bool {
		return v1beta1helper.GetCondition(shoot.Status.Constraints, gardencorev1beta1.ShootReadyForMigration) != nil && !v1beta1helper.ShootHasOperationType(shoot.Status.LastOperation, gardencorev1beta1.LastOperationTypeMigrate)
	}

	return predicate.Funcs{
		CreateFunc: func(e event.CreateEvent) bool {
			shoot, ok := e.Object.(*gardencorev1beta1.Shoot)
			if !ok {
				return false
			}

			return v1beta1helper.ShouldPrepareShootForMigration(shoot) || requireConstraintRemoval(shoot)
		},
		UpdateFunc: func(e event.UpdateEvent) bool {
			newShoot, ok := e.ObjectNew.(*gardencorev1beta1.Shoot)
			if !ok {
				return false
			}

			oldShoot, ok := e.ObjectOld.(*gardencorev1beta1.Shoot)
			if !ok {
				return false
			}

			return ptr.Deref(oldShoot.Spec.SeedName, "") != ptr.Deref(newShoot.Spec.SeedName, "") || requireConstraintRemoval(newShoot)
		},
		DeleteFunc: func(_ event.DeleteEvent) bool {
			return false
		},
		GenericFunc: func(_ event.GenericEvent) bool {
			return false
		},
	}
}