kubernetes/kops · error

creating accessor for %v: %w

Error message

creating accessor for %v: %w

What it means

While iterating over the listed items, dumpGVRNamespaces calls meta.Accessor(obj) on each runtime.Object to get its ObjectMeta so it can strip managedFields and mask secrets. If an object does not implement metav1.Object (no GetObjectMeta/Name/Namespace accessor), meta.Accessor returns an error, which is wrapped as "creating accessor for %v: %w" for the whole job's resource list.

Source

Thrown at pkg/dump/resourcedumper.go:234

				err: fmt.Errorf("creating file %q: %w", resPath, err),
			}
			continue
		}

		err = resourceList.EachListItem(func(obj runtime.Object) error {
			o, err := meta.Accessor(obj)
			if err != nil {
				return err
			}
			o.SetManagedFields(nil)
			if err := maskObject(obj); err != nil {
				return err
			}
			return nil
		})
		if err != nil {
			results <- resourceDumpResult{
				err: fmt.Errorf("creating accessor for %v: %w", job, err),
			}
			continue
		}
		contents, err := resourceList.MarshalJSON()
		if err != nil {
			results <- resourceDumpResult{
				err: fmt.Errorf("marshaling to json for %v: %w", job, err),
			}
			continue
		}

		switch d.output {
		case "yaml":
			contents, err = yaml.JSONToYAML(contents)
			if err != nil {
				results <- resourceDumpResult{
					err: fmt.Errorf("marshaling to yaml for %v: %w", job, err),
				}

View on GitHub (pinned to 4c8573c808)

Solutions

1. Identify the GVR/namespace named in the error (%v job) and test `kubectl get --raw /apis/<group>/<version>/<resource>?fieldSelector=metadata.namespace=<ns>` to inspect the served response.
2. Check the API server serving that resource (CRD or aggregated apiserver) for version skew or bugs; upgrade/fix it.
3. Skip the problematic resource via the dumper's ignoredResources path or upgrade kOps to pick up resilience fixes.
4. Re-run the dump; transient corrupted responses may disappear once the API server is healthy.

Example fix

// before
o, err := meta.Accessor(obj)
// after (guard against nil/unexpected items)
if obj == nil || obj.GetObjectKind() == nil {
  return nil // skip malformed item
}
o, err := meta.Accessor(obj)

func hasMeta(obj runtime.Object) (metav1.Object, bool) {
  if obj == nil { return nil, false }
  o, err := meta.Accessor(obj)
  return o, err == nil
}

// Go: errors are values — recover like a catch by unwrapping the cause
if err := runDump(); err != nil {
  if strings.Contains(err.Error(), "creating accessor for") {
    // identify job from message, verify resource with kubectl, skip or retry
  }
  return err
}

When it happens

Trigger: The dynamic client returns list items that cannot be accessed as metav1.Object — typically a nil object, a malformed/unregistered type returned by an aggregated API server or a CRD serving non-standard responses, or an unexpected item type inside UnstructuredList.

Common situations: A custom resource served by a nonconforming aggregated API server; a CRD webhook returning list items without proper ObjectMeta; corrupted responses from an older/damaged Kubernetes version; nil entries in a list produced by a broken controller.

Related errors

• error listing objects: %w
• error listing objects in namespace %s: %w
• building dynamic client: %w
• node identity is required
• did not find owner for node %q

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/5a80e1da39fc83d5. Report an issue: GitHub.