ahmetb/kubectx · error

failed to list namespaces from k8s API: %w

Error message

failed to list namespaces from k8s API: %w

What it means

A paginated CoreV1().Namespaces().List call against the cluster API failed. Causes: RBAC denying namespace list to the authenticated user, API server errors, or the connection dropping mid-pagination (the code loops with Limit 500 + Continue tokens).

Source

Thrown at cmd/kubens/list.go:98

		return []string{"ns1", "ns2"}, nil
	}

	clientset, err := newKubernetesClientSet(kc)
	if err != nil {
		return nil, fmt.Errorf("failed to initialize k8s REST client: %w", err)
	}

	var out []string
	var next string
	for {
		list, err := clientset.CoreV1().Namespaces().List(
			context.Background(),
			metav1.ListOptions{
				Limit:    500,
				Continue: next,
			})
		if err != nil {
			return nil, fmt.Errorf("failed to list namespaces from k8s API: %w", err)
		}
		next = list.Continue
		out = slices.Grow(out, len(list.Items))
		for _, it := range list.Items {
			out = append(out, it.Name)
		}
		if next == "" {
			break
		}
	}
	return out, nil
}

func newKubernetesClientSet(kc *kubeconfig.Kubeconfig) (*kubernetes.Clientset, error) {
	var cfg *rest.Config
	var err error

	if paths := kc.ConfigPaths(); len(paths) > 0 {

View on GitHub (pinned to 12ad6fb22e)

Solutions

  1. Verify RBAC: kubectl auth can-i list namespaces
  2. Retry in case of transient API server unavailability
  3. Check the wrapped API error for Forbidden/Timeout details
Defensive patterns

Strategy: retry

When it happens

Trigger: Thrown at cmd/kubens/list.go:98 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of ahmetb/kubectx@12ad6fb22e (2026-09-02). Data as JSON: /api/errors/a53898903b5ea57f. Report an issue: GitHub.