FeignException class

The error a Feign client method throws when its call fails.

It carries what is known about the failure: the status of the response (-1 when there was none), the request, and the response body and headers. An error status is thrown as a subclass, so callers catch the cases they handle: FeignNotFound for a 404, FeignClientException for any 4xx, FeignServerException for any 5xx (see FeignException.errorStatus). A call that got no answer throws a RetryableException; a body that does not fit the return type a DecodeException. An ErrorDecoder bean can throw exceptions of your own instead.

// A missing book is not an error for the shop; anything else is.
try {
  await catalog.find('978-0');
} on FeignNotFound {
  return null;
} on FeignException catch (error) {
  log.warning('${error.status}: ${error.responseBody}');
}

Spring (Java):

try { catalog.find("978-0"); }
catch (FeignException.NotFound e) { return null; }

Implemented types

Exception

Constructors

FeignException(int status, String message, {HttpRequest? request, String? responseBody, HttpHeaders? responseHeaders, Object? cause}): A failure with status (-1 without a response) and message.

Properties

cause → Object?: The error that caused this one, such as an HttpTransportException for a failed connection; null when none.
final
hashCode → int: The hash code for this object.
no setterinherited
message → String: What happened, in Feign's form: [404 Not Found] during [GET] to [<url>] [<method key>].
final
request → HttpRequest?: The request that failed, when known.
final
responseBody → String?: The response body as text, often an error message or a problem document from the server; null without a response.
final
responseHeaders → HttpHeaders?: The response headers; null without a response.
final
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
status → int: The status of the response; -1 when no response was received.
final

Methods

noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
toString() → String: The class, the message and a preview of the responseBody, as Feign's message has: the whole body under 400 bytes, else its first 200 characters and its size (... (5120 bytes)). responseBody keeps all of it.
override

Operators

operator ==(Object other) → bool: The equality operator.
inherited

Static Methods

errorStatus(String methodKey, HttpResponse response) → FeignException: The exception for the error response of the method methodKey (CatalogClient#find(String)): the subclass for its status (such as FeignNotFound), else a FeignClientException for another 4xx, a FeignServerException for another 5xx, or a plain FeignException for any other status. An ErrorDecoder of your own may call it for the statuses it leaves alone.