Why Reconcile function is called many times in controller_test.go ?

[LittleWat]

Hello. I am new to kubebuilder.

Now I am implementing a controller_test that verifies the mock function called Once using testify.

But the Reconcile function is called many times even though I return &ctrl.Result{Requeue: false} in Reconcile function.

Is it possible to call Reconcile function once in test codes...?

[camilamacedo86]

Hi @LittleWat,

By using the Operators, it’s possible not only to provide all expected resources but also to manage them dynamically, programmatically, and at runtime. To illustrate this idea, imagine if someone accidentally changed a configuration or removed a resource by mistake; in this case, the Operator could fix it without any human intervention.

Therefore, the goal is to always ensure a desired state on the cluster via idempotent solutions, and because of this, we "watch" the required resources on the cluster and when something changes we reconcile.

TL'DR: I recommend you check the common suggestions doc under the best practices section on the SDK website, see: https://sdk.operatorframework.io/docs/best-practices/common-recommendation/. for further info

Regards your question:

Now I am implementing a controller_test that verifies the mock function called Once using testify.

Not sure how you are doing this implementation but a good example can be found in the scaffold done by the new plugin deploy.image/v1-alpha, see: https://github.com/kubernetes-sigs/kubebuilder/blob/master/testdata/project-v3-with-deploy-image/controllers/busybox_controller_test.go#L36-L125

But the Reconcile function is called many times even though I return &ctrl.Result{Requeue: false} in Reconcile function.

Again not sure how you are doing that. If it is called more than once or it is returning errors which will make the reconciliation begin again or the resources which are watched have been changed and then are calling the reconciliation again.

Also, see the blog: https://dev4devs.com/2020/08/16/how-to-getting-started-develop-go-operators-from-scratch-with-sdk-1-0/ it has good info about getting started and describes the returns for the reconcile.

[LittleWat]

Thank you for your quick and detailed answer!!!
This helps me a lot.

https://github.com/kubernetes-sigs/kubebuilder/blob/master/testdata/project-v3-with-deploy-image/controllers/busybox_controller_test.go#L36-L125

Ah, I misunderstood that I had to create k8sManager like below and that Reconcile function should be called from the manager.

	k8sManager, err := ctrl.NewManager(cfg, ctrl.Options{
		Scheme: scheme.Scheme,
	})
	Expect(err).ToNot(HaveOccurred())

But it was not necessary. Just calling Reconcile function satisfies what I wanted to do!

[camilamacedo86]

That is necessary to pass the API Schemas to the mock manager.

[LittleWat]

Yes, I misunderstood that kubebuilder tests always need the step to create a manager and set up a reconsiler with the manager like the sample code below:

https://book.kubebuilder.io/cronjob-tutorial/writing-tests.html

    k8sManager, err := ctrl.NewManager(cfg, ctrl.Options{
        Scheme: scheme.Scheme,
    })
    Expect(err).ToNot(HaveOccurred())

    err = (&CronJobReconciler{
        Client: k8sManager.GetClient(),
        Scheme: k8sManager.GetScheme(),
    }).SetupWithManager(k8sManager)
    Expect(err).ToNot(HaveOccurred())

Anyway, I could have solved this issue, and really appreciate your help! 🙇

[camilamacedo86]

Closing since it is answered.

[LittleWat]

thank you!