Add get_or_create for resources

[RonZhang724]

It would be nice to be able call get_or_create on long lasting resources such as NameSpace, ServiceAccount etc.

This will reduce verbosity in some cases. For example this function:

func CreateNamespace(kubeClient kubernetes.Interface, name string) (*v1.Namespace, error) {
	existingNamespace, err := kubeClient.CoreV1().Namespaces().Get(context.TODO(), name, metav1.GetOptions{})
	if err == nil {
		return existingNamespace, nil
	}

	namespace, err := kubeClient.CoreV1().Namespaces().Create(context.TODO(), &v1.Namespace{
		ObjectMeta: metav1.ObjectMeta{
			Name: name,
		},
	},
		metav1.CreateOptions{},
	)
	if err != nil {
		return nil, errors.Wrap(err, fmt.Sprintf("failed to create namespace with name %v", name))
	}
	return namespace, nil
}

Can be reduced to:

func CreateNamespace(kubeClient kubernetes.Interface, name string) (*v1.Namespace, error) {
	namespace, err := kubeClient.CoreV1().Namespaces().getOrCreate(context.TODO(), &v1.Namespace{
		ObjectMeta: metav1.ObjectMeta{
			Name: name,
		},
	},
		metav1.CreateOptions{},
	)
	if err != nil {
		return nil, errors.Wrap(err, fmt.Sprintf("failed to create namespace with name %v", name))
	}
	return namespace, nil
}

[grzesuav]

I think more sense have create_or_update (as in controller-runtime) because in what you propose : what to do if resource exists but differ ?

[k8s-triage-robot]

The Kubernetes project currently lacks enough contributors to adequately respond to all issues and PRs.

This bot triages issues and PRs according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Mark this issue or PR as fresh with /remove-lifecycle stale
• Mark this issue or PR as rotten with /lifecycle rotten
• Close this issue or PR with /close
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle stale

[k8s-triage-robot]

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues and PRs.

This bot triages issues and PRs according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Mark this issue or PR as fresh with /remove-lifecycle rotten
• Close this issue or PR with /close
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle rotten

[k8s-triage-robot]

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues and PRs.

This bot triages issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Reopen this issue with /reopen
• Mark this issue as fresh with /remove-lifecycle rotten
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/close not-planned

[k8s-ci-robot]

@k8s-triage-robot: Closing this issue, marking it as "Not Planned".

In response to this:

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues and PRs.

This bot triages issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Reopen this issue with /reopen
• Mark this issue as fresh with /remove-lifecycle rotten
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/close not-planned

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.