The WWW-Authenticate challege returned to the clien tin a 401 response for invalid requests
An error header, consisting of the challenge and possibly an error and error_description attribute (this depends on the authentication scheme).
Return a function representing an error response
The response for failed authentication attempts.
The response for failed authentication attempts. Intended to be overridden by authentication schemes that have differing requirements.
Represents the scheme used for decoding access tokens from a given requests.