✨ Add controller option for setting leader election

[jonstacks]

Background

Creating a controller that is not leader elected is seems to require a bit of indirection. You currently have to create a new type that embeds the Controller interface and adds a NeedLeaderElection method as shown below so that it implements the manager.LeaderElectionRunnable interface.

type MyReconciler struct {
	client.Client
	Log      logr.Logger
	Scheme   *runtime.Scheme
	Recorder record.EventRecorder
}

func (rec *MyReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
	return ctrl.Result{}, nil
}

func (rec *MyReconciler) SetupWithManager(mgr ctrl.Manager) error {
	cont, err := controller.NewUnmanaged("my-controller", mgr, controller.Options{
		Reconciler: rec,
	})
	if err != nil {
		return err
	}
	cont = MyController{cont}
	cont.Watch(&source.Kind{Type: &netv1.Ingress{}}, &handler.EnqueueRequestForObject{}, commonPredicateFilters)
	return mgr.Add(cont)
}

type MyController struct {
	controller.Controller
}

func (c *MyController) NeedLeaderElection() bool {
	return false
}

What

This PR adds a new controller option, LeaderElected, that can be used to disable leader election for the controller, without having to create a new type.

How

It does this by making controller.Controller implement the manager.LeaderElectionRunnable interface.

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[k8s-ci-robot]

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[alvaroaleman]

/ok-to-test

[alvaroaleman]

thanks!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: alvaroaleman, jonstacks

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