Errors

Undici exposes a variety of error objects that you can use to enhance your error handling. You can find all the error objects inside the errors key.

import { errors } from 'undici'

Error	Error Codes	Description
UndiciError	UND_ERR	all errors below are extended from UndiciError.
ConnectTimeoutError	UND_ERR_CONNECT_TIMEOUT	socket is destroyed due to connect timeout.
HeadersTimeoutError	UND_ERR_HEADERS_TIMEOUT	socket is destroyed due to headers timeout.
HeadersOverflowError	UND_ERR_HEADERS_OVERFLOW	socket is destroyed due to headers' max size being exceeded.
BodyTimeoutError	UND_ERR_BODY_TIMEOUT	socket is destroyed due to body timeout.
ResponseStatusCodeError	UND_ERR_RESPONSE_STATUS_CODE	an error is thrown when throwOnError is true for status codes >= 400.
InvalidArgumentError	UND_ERR_INVALID_ARG	passed an invalid argument.
InvalidReturnValueError	UND_ERR_INVALID_RETURN_VALUE	returned an invalid value.
RequestAbortedError	UND_ERR_ABORTED	the request has been aborted by the user
ClientDestroyedError	UND_ERR_DESTROYED	trying to use a destroyed client.
ClientClosedError	UND_ERR_CLOSED	trying to use a closed client.
SocketError	UND_ERR_SOCKET	there is an error with the socket.
NotSupportedError	UND_ERR_NOT_SUPPORTED	encountered unsupported functionality.
RequestContentLengthMismatchError	UND_ERR_REQ_CONTENT_LENGTH_MISMATCH	request body does not match content-length header
ResponseContentLengthMismatchError	UND_ERR_RES_CONTENT_LENGTH_MISMATCH	response body does not match content-length header
InformationalError	UND_ERR_INFO	expected error with reason
ResponseExceededMaxSizeError	UND_ERR_RES_EXCEEDED_MAX_SIZE	response body exceed the max size allowed
SecureProxyConnectionError	UND_ERR_PRX_TLS	tls connection to a proxy failed

SocketError

The SocketError has a .socket property which holds socket metadata:

interface SocketInfo {
  localAddress?: string
  localPort?: number
  remoteAddress?: string
  remotePort?: number
  remoteFamily?: string
  timeout?: number
  bytesWritten?: number
  bytesRead?: number
}

Be aware that in some cases the .socket property can be null.