hasura/graphql-engine · error

error in marshalling actions, custom_types from metadata: %w

Error message

error in marshalling actions, custom_types from metadata: %w

What it means

Export fails when the actions metadata struct cannot be re-serialized to YAML. After Build produces the actions object, Export encodes it with the YAML encoder; a marshal failure means the in-memory struct contains data the encoder cannot represent.

Source

Thrown at cli/internal/metadataobject/actions/actions.go:578

	if err != nil {
		return nil, errors.E(op, a.error(err))
	}

	actions := map[string]yaml.Node{}
	if v, ok := metadata[metadataobject.ActionsKey]; ok {
		actions[metadataobject.ActionsKey] = v
	}

	if v, ok := metadata[metadataobject.CustomTypesKey]; ok {
		actions[metadataobject.CustomTypesKey] = v
	}

	ymlByt := new(bytes.Buffer)
	if err := metadataobject.GetEncoder(ymlByt).Encode(actions); err != nil {
		return nil, errors.E(
			op,
			a.error(
				fmt.Errorf("error in marshalling actions, custom_types from metadata: %w", err),
			),
		)
	}

	var common types.Common

	err = yaml.NewDecoder(ymlByt).Decode(&common)
	if err != nil {
		return nil, errors.E(op, a.error(fmt.Errorf("error in unmarshal to common: %w", err)))
	}

	var sdlToReq types.SDLToRequest

	sdlToReq.Types = common.CustomTypes
	sdlToReq.Actions = common.Actions

	sdlToResp, err := a.cliExtensionConfig.ConvertMetadataToSDL(sdlToReq)
	if err != nil {

View on GitHub (pinned to 724551b9ae)

Solutions

1. Inspect the actions metadata input for unusual values (non-string map keys, invalid types) and normalize them
2. Re-load and rebuild metadata from a known-good export
3. Report upstream if the struct itself fails to marshal with valid metadata

files, err := actionsObj.Export(ctx)
if err != nil {
  if strings.Contains(err.Error(), "error in marshalling actions") {
    // inspect/normalize the source metadata, then retry with cleaned metadata
  }
  return err
}

When it happens

Trigger: Calling Export() when the actions struct contains fields that cannot be YAML-encoded, such as unsupported map key types, NaN/Inf floats, or corrupted internal state after a partial build.

Common situations: Metadata loaded from an exotic or hand-edited YAML file that unmarshals into a degenerate struct; upstream schema changes introducing non-serializable fields.

Related errors

• error in marshaling common: %w
• unable to marshal run_sql args in %s: %w
• error in marshalling common: %w
• error in unmarshal to common: %w
• unable to unmarshal run_sql args in %s: %w

AI-assisted analysis of hasura/graphql-engine@724551b9ae (2026-08-28). Data as JSON: /api/errors/8fdedcfd280757a8. Report an issue: GitHub.