Controllers creating/watching resources in different namespace than their Custom Resource

Question

I have a controller which Reconciles MyKind Custom Resource in 'foo' namespace. Within the reconcile loop, it creates a deployment MyDeployment in 'bar' namespace. I am wondering how can I setup a watch on the MyDeployment created in 'bar' namespace which is different than namespace ('foo') where the custom resource live.

I tried setting up my manager with the following, but it doesnt seem to work since the deployment I am trying to watch are in different namespace hence the controller is not able to receive any events for the CRUD operation on the deployment.

    return controllerruntime.NewControllerManagedBy(mgr).
        For(&v1alpha1.MyKind{}).
        Owns(&appsv1.Deployment{}).
        Complete(r)
}

Is there any custom watch that I can configure my controller with in order to receive events for the deployment in a different namespace.

Note: I tried handler.EnqueueRequestsFromMapFunc, IIUC it also reconciles for Kinds in the same namespace.

Hi Kapoor, did you found a solution because I have the same with kubebuilder-v3 — Quentin, Apr 19 '22 at 14:11

score 1 · Answer 1 · answered Nov 30 '20 at 20:36

1

You can specify namespaces in the manager options by passing in a ctrl.Options{} object, while creating it.

namespace := "namespace1,namespace2"
options := ctrl.Options{
        .
        .
        .
        Namespace: cache.MultiNamespacedCacheBuilder(strings.Split(namespace, ","))
    }

mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), options)

answered Nov 30 '20 at 20:36

Hazim

1,405
1
11
24

Hello Hazim, thank you for quick answer, The namespaces are not known before starting the Manager, Is there a way that we can do this after the manager is started ? – Kapoor Akul Dec 01 '20 at 10:28
Setting the `Namespace` property to an empty string should make the controller look in all namespaces. You then need to make sure that you deploy it with the correct RBAC, allowing it to read in all namespaces probably – Hazim Dec 01 '20 at 16:05
`Namespace` is of string type. Correct attribute is `NewCache` – Arun Feb 14 '23 at 09:43

score 1 · Answer 2 · answered Oct 11 '22 at 08:35

You can use MultiNamespacedCacheBuilder as the NewCache function when creating manager. This can be set in manager.Options.

For example:

namespace := "ns1,ns1"
options := ctrl.Options{
    .
    .
    .
    NewCache: cache.MultiNamespacedCacheBuilder(strings.Split(namespace, ","))
}

mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), options)

Controllers creating/watching resources in different namespace than their Custom Resource

2 Answers2