hyperledger/fabric · error

failed to marshal chaincode package metadata into JSON

Error message

failed to marshal chaincode package metadata into JSON

What it means

Wrapping error in toJSON: json.Marshal failed on the PackageMetadata struct (path/type/label) while assembling a chaincode package. This is highly unusual since the struct is plain strings; it indicates an environment/JSON package anomaly rather than user input, and the failure aborts packaging of the .tar.gz metadata file.

Source

Thrown at internal/peer/lifecycle/chaincode/package.go:231

}

// PackageMetadata holds the path and type for a chaincode package
type PackageMetadata struct {
	Path  string `json:"path"`
	Type  string `json:"type"`
	Label string `json:"label"`
}

func toJSON(path, ccType, label string) ([]byte, error) {
	metadata := &PackageMetadata{
		Path:  path,
		Type:  ccType,
		Label: label,
	}

	metadataBytes, err := json.Marshal(metadata)
	if err != nil {
		return nil, errors.Wrap(err, "failed to marshal chaincode package metadata into JSON")
	}

	return metadataBytes, nil
}

View on GitHub (pinned to 2736b63f8f)

Solutions

1. Inspect the wrapped error for the specific marshal failure
2. Verify the path/type/label strings contain valid UTF-8 (invalid bytes can fail JSON encoding)
3. Retry the package lifecycle chaincode package command; if persistent, report as an environment bug

When it happens

Trigger: Thrown at internal/peer/lifecycle/chaincode/package.go:231 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/83b2b47e1b3fab2d. Report an issue: GitHub.