Errors

Every failure throws, or rejects with, a JavaScript Error whose code names it.

OT_<CODE>: a failure of the core. code is OT_ followed by the core’s stable code, message is the core’s human-readable text, and legacyMessage is the message of the matching Python exception; an OT_ error without one, such as an SRP refusal, repeats message there.
ERR_INVALID_ARG_VALUE: an argument the binding rejects before the core sees it, such as an unknown client name or a wrongly typed patch; it has no legacyMessage.

errors.mjs


import { loadTdata } from 'opentele2'
 
try {
  await loadTdata('tdata', 'wrong passcode')
} catch (error) {
  if (error.code === 'OT_TDATA_BAD_DECRYPT_KEY') console.log('wrong or missing passcode')
  else if (error.code === 'OT_TFILE_NOT_FOUND') console.log(error.legacyMessage) // Could not open key_data
  else throw error
}

code values are stable across releases; message may change, so match on code. Each row below names the exception the Python package raises for the same failure.

Core codes

`code`	Raised when
`OT_TFILE_NOT_FOUND`	A required tdata file or `.session` file does not exist. Python: `TFileNotFound`.
`OT_TDATA_INVALID_MAGIC`	A tdata file does not start with `TDF$`, or the MTP data holds an unknown block. Python: `TDataInvalidMagic`.
`OT_TDATA_INVALID_CHECKSUM`	A tdata file’s MD5 checksum does not match its contents. Python: `TDataInvalidCheckSum`.
`OT_TDATA_BAD_DECRYPT_KEY`	Decryption does not match its key: the passcode is missing or wrong. Python: `TDataBadDecryptKey`.
`OT_TDATA_WRONG_PASSCODE`	The local passcode does not unlock the folder. Python: `TDataWrongPasscode`.
`OT_TDATA_BAD_ENCRYPTED_DATA_SIZE`	Encrypted data has a size AES-IGE cannot take. Python: `TDataBadEncryptedDataSize`.
`OT_TDATA_BAD_DECRYPTED_DATA_SIZE`	Decrypted data declares a size that does not fit. Python: `TDataBadDecryptedDataSize`.
`OT_TDATA_BAD_CONFIG_DATA`	An MTP config, endpoint or session row does not parse, or the main DC has no endpoint. Python: `TDataBadConfigData`.
`OT_QDATASTREAM_FAILED`	A Qt data stream read failed, or a `.session` file has another layout or version. Python: `QDataStreamFailed`.
`OT_TDATA_READ_MAP_DATA_FAILED`	An account’s `maps` file cannot be read. Python: `TDataReadMapDataFailed`.
`OT_TDATA_READ_MAP_DATA_INCORRECT_PASSCODE`	An account’s map was read with a wrong passcode. Python: `TDataReadMapDataIncorrectPasscode`.
`OT_TDATA_AUTH_KEY_NOT_FOUND`	No auth key for the main DC, or no row or key in a `.session` file. Python: `TDataAuthKeyNotFound`.
`OT_MAX_ACCOUNT_LIMIT`	A folder would hold more accounts than it may. Python: `MaxAccountLimit`.
`OT_TDATA_SAVE_FAILED`	Saving failed: no accounts, duplicate indices or an empty key file name. Python: `TDataSaveFailed`.
`OT_TDATA_KEY_DATA_INVALID`	The key file is malformed or its passcode wrap parameters are unusable. Python: `TDataKeyDataInvalid`.
`OT_BAD_LENGTH`	A buffer, key or IV has the wrong length. Python: `ValueError`.
`OT_INVALID_INPUT`	An argument is outside what the operation accepts. Python: `ValueError`.
`OT_IO`	A file operation failed, or data is not what it should be (gzip, session JSON). Python: `OSError`.

Flow and SRP codes

The client flows of opentele2/mtcute and srpCheck fail with these; the name of a flow error is its Python exception class.

`code`	Raised when
`OT_NO_PASSWORD_PROVIDED`	A QR login met 2FA without a password. Python: `NoPasswordProvided`.
`OT_PASSWORD_INCORRECT`	`auth.checkPassword` failed with `PASSWORD_HASH_INVALID`. Python: `PasswordIncorrect`.
`OT_AUTH_TOKEN_ALREADY_ACCEPTED`	The QR login token was accepted already. Python: `AuthTokenAlreadyAcceptedError`.
`OT_AUTH_TOKEN_EXPIRED`	The QR login token expired. Python: `AuthTokenExpiredError`.
`OT_AUTH_TOKEN_INVALID`	The QR login token is invalid. Python: `AuthTokenInvalidError`.
`OT_QR_LOGIN_TIMEOUT`	No QR login attempt logged in. Python: `TimeoutError`.
`OT_FRESH_RESET_FORBIDDEN`	A session cannot be terminated within 24 hours of login. Python: `FreshResetAuthorisationForbiddenError`.
`OT_HASH_INVALID`	`terminateSession` was given an unknown hash. Python: `HashInvalidError`.
`OT_UNSUPPORTED_PASSWORD_ALGORITHM`	The 2FA password uses an algorithm other than `SRP_ALGORITHM`. Python: `ValueError`.
`OT_SIGN_UP_REQUIRED`	The server asked to sign up instead of logging in. Python: `SignUpRequired`.
`OT_USER_ID_UNRESOLVED`	The self user of a client cannot be resolved. Python: `TelethonUnauthorized`.
`OT_SESSIONS_UNAVAILABLE`	The account’s sessions cannot be fetched. Python: `OpenTeleException`.
`OT_SRP_BAD_PRIME_OR_GENERATOR`	The 2FA `p` or `g` is not acceptable. Python: `ValueError`.
`OT_SRP_BAD_B`	The server’s `srpB` is out of range or missing. Python: `ValueError`.
`OT_SRP_NO_GOOD_RANDOM`	Every random draw for the SRP exponent was unusable. Python: `ValueError`.
`OT_SRP_RANDOM_UNAVAILABLE`	The OS random source failed during the SRP check. Python: `ValueError`.

index.d.ts


function flowErrorClasses(): Record<string, string>

flowErrorClasses() returns the Python class name of every flow and SRP code above, by OT_ code.