var errorMessages = { 'LIMIT_PART_COUNT': 'Too many parts', 'LIMIT_FILE_SIZE': 'File too large', 'LIMIT_FILE_COUNT': 'Too many files', 'LIMIT_FIELD_KEY': 'Field name too long', 'LIMIT_FIELD_VALUE': 'Field value too long', 'LIMIT_FIELD_COUNT': 'Too many fields', 'LIMIT_UNEXPECTED_FILE': 'Unexpected field' } function makeError (code, optionalField) { var err = new Error(errorMessages[code]) err.code = code if (optionalField) err.field = optionalField return err } module.exports = makeError