kubernetes/kops · error

marshaling kops-channels pod: %w

Error message

marshaling kops-channels pod: %w

What it means

After the kops-channels pod object is built, k8scodecs.ToVersionedYaml serializes it to a versioned YAML manifest for the ManagedFile task. This error wraps a serialization failure — rare, and indicates the in-memory pod object could not be converted to a versioned API type.

Source

Thrown at pkg/model/components/channels/model.go:74

	Lifecycle    fi.Lifecycle
	AssetBuilder *assets.AssetBuilder
}

var _ fi.CloudupModelBuilder = &ChannelsBuilder{}

func (b *ChannelsBuilder) Build(c *fi.CloudupModelBuilderContext) error {
	channels, err := b.channelList()
	if err != nil {
		return err
	}

	pod, err := b.buildPod(channels)
	if err != nil {
		return fmt.Errorf("building kops-channels pod: %w", err)
	}
	manifest, err := k8scodecs.ToVersionedYaml(pod)
	if err != nil {
		return fmt.Errorf("marshaling kops-channels pod: %w", err)
	}

	c.AddTask(&fitasks.ManagedFile{
		Contents:  fi.NewBytesResource(manifest),
		Lifecycle: b.Lifecycle,
		Location:  new(channelsManifestPath),
		Name:      new("manifests-channels-kops-channels"),
	})
	return nil
}

// channelList returns the bootstrap channel plus cluster.Spec.Addons. The bootstrap URL is
// built via vfs path joining so toolbox_enroll's identity comparison stays byte-identical.
func (b *ChannelsBuilder) channelList() ([]string, error) {
	configBase, err := vfs.Context.BuildVfsPath(b.Cluster.Spec.ConfigStore.Base)
	if err != nil {
		return nil, fmt.Errorf("parsing configStore.base %q: %w", b.Cluster.Spec.ConfigStore.Base, err)
	}

View on GitHub (pinned to 4c8573c808)

Solutions

1. Run `make gomod` / `make kops` to ensure k8s.io/api and apimachinery versions are consistent
2. Check the wrapped inner error for the offending field and remove/fix it in custom builder code
3. Pin the k8s.io/api & codec dependency versions to those in kops go.mod

Example fix

// before: pod object with unmarshalable field
pod.Spec.Containers = append(pod.Spec.Containers, badContainer)
// after: validate fields exist in the k8s API version being coded
pod.Spec.Containers = append(pod.Spec.Containers, validContainer)

if _, err := k8scodecs.ToVersionedYaml(pod); err != nil { return fmt.Errorf("channels pod not serializable: %w", err) }

if err := buildChannels(); err != nil {
	if strings.Contains(err.Error(), "marshaling kops-channels pod") {
		// suspect dependency skew: check k8s.io/api versions
	}
	return err
}

When it happens

Trigger: ToVersionedYaml fails on the constructed v1.Pod, e.g. the pod object contains fields that cannot round-trip through the targeted codec/version.

Common situations: Mixed kops/k8s.io/api library version skew during a custom build; a bug in a patched channels builder injecting invalid fields; vendored dependency drift after `go mod` changes.

Related errors

• error marshaling yaml: %v
• error writing yaml to stdout: %v
• unable to marshal YAML: %v
• unable to marshal YAML: %v
• unable to marshal YAML: %v

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/6f5d4b07f6f7c4d7. Report an issue: GitHub.