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Predicate authenticate/3
 http:authenticate(+AuthData, +Request, -Fields)[multifile, library(http/http_authenticate)]
Plugin for library(http_dispatch) to perform basic HTTP authentication.

This predicate throws http_reply(authorise(basic, Realm)).

Arguments:
AuthData- must be a term basic(File, Realm)
Request- is the HTTP request
Fields- describes the authenticated user with the option user(User) and with the option user_details(Fields) if the password file contains additional fields after the user and password.
 http:authenticate(+Digest, +Request, -Fields)[multifile, library(http/http_digest)]
Plugin for library(http_dispatch) to perform basic HTTP authentication. Note that we keep the authentication details cached to avoid a `nonce-replay' error in the case that the application tries to verify multiple times.

This predicate throws http_reply(authorise(digest(Digest)))

Arguments:
Digest- is a term digest(File, Realm, Options)
Request- is the HTTP request
Fields- describes the authenticated user with the option user(User) and with the option user_details(Fields) if the password file contains additional fields after the user and password.