GoogleContainerTools/skaffold · error

unable to re-marshal YAML without dotted keys: %w

Error message

unable to re-marshal YAML without dotted keys: %w

What it means

During parsing, Skaffold re-marshals the YAML after removing anchors/dotted keys so downstream decoders see normalized YAML. If that re-marshal step fails, ParseConfig returns this wrapped error. It indicates the YAML round-trip could not be serialized, usually due to unsupported constructs produced by the decode step.

Source

Thrown at pkg/skaffold/schema/versions.go:239

	if config, err := ParseConfig(file); err == nil && config != nil {
		return true
	}
	return false
}

// ParseConfig reads a configuration file.
func ParseConfig(filename string) ([]util.VersionedConfig, error) {
	buf, err := misc.ReadConfiguration(filename)
	if err != nil {
		return nil, fmt.Errorf("read skaffold config: %w", err)
	}
	factories, err := configFactoryFromAPIVersion(buf)
	if err != nil {
		return nil, err
	}
	buf, err = removeYamlAnchors(buf)
	if err != nil {
		return nil, fmt.Errorf("unable to re-marshal YAML without dotted keys: %w", err)
	}
	return parseConfig(buf, factories)
}

// ParseConfigAndUpgrade reads a configuration file and upgrades it to a given version.
func ParseConfigAndUpgrade(filename string) ([]util.VersionedConfig, error) {
	configs, err := ParseConfig(filename)
	if err != nil {
		return nil, err
	}

	return UpgradeTo(configs, latest.Version)
}

// configFactoryFromAPIVersion checks that all configs in the input stream have the same API version, and returns a function to create a config with that API version.
func configFactoryFromAPIVersion(buf []byte) ([]func() util.VersionedConfig, error) {
	// This is to quickly check that it's possibly a skaffold.yaml,
	// without parsing the whole file.

View on GitHub (pinned to a1189de023)

Solutions

1. Simplify the YAML in skaffold.yaml: remove dotted keys and non-standard constructs
2. Replace YAML anchors/merge keys with explicit values to avoid the rewrite path
3. Bisect by halving the config file to find the offending document/section
4. Inspect the wrapped cause (%w) for the marshal error detail

Example fix

# before (dotted key)
.x-custom: value
apiVersion: skaffold/v4beta7
# after
apiVersion: skaffold/v4beta7

configs, err := schema.ParseConfig(cfgPath)
if err != nil {
	var reErr *fmt.Errorf
	if strings.Contains(err.Error(), "re-marshal YAML without dotted keys") {
		// simplify YAML: remove dotted keys/anchors, then retry once
	}
	return err
}

When it happens

Trigger: Calling ParseConfig on a file whose YAML, after removeYamlAnchors processing, cannot be re-marshaled — e.g. exotic key types or constructs the marshal step cannot represent.

Common situations: Highly unusual YAML in skaffold.yaml (odd key types, corrupt encoding); a bug/edge case in the anchor-removal pipeline triggered by unusual document structure.

Related errors

• parsing api version: %w
• unable to parse YAML: %w
• read skaffold config: %w
• `apply` requires at least one manifest argument
• `exec` requires exactly one action to execute

AI-assisted analysis of GoogleContainerTools/skaffold@a1189de023 (2026-09-05). Data as JSON: /api/errors/e8c46302c4288ae8. Report an issue: GitHub.