user_db.pl -- User administration

Core user administration. The user administration is based on the following:

• A persistent fact user/2
• A dynamic fact logged_in/4
• Session management

See also

- preferences.pl implements user preferences

- openid.pl implements OpenID server and client

 set_user_database(+File) is det

Load user/2 from File. Changes are fully synchronous.

 user_add(+Name, +Properties) is det

Add a new user with given properties.

 user_del(+Name)

Delete named user from user-database.

 set_user_property(+Name, +Property) is det

Replace Property for user Name.

 openid_add_server(+Server, +Options)

Register an OpenID server.

 openid_del_server(+Server)

Delete registration of an OpenID server.

 openid_set_property(+Server, +Property) is det

Replace Property for OpenID Server

 openid_current_server(?Server) is nondet

 openid_server_properties(+Server, -Properties) is semidet

Try find properties for the given server. Note that we generally refer to a server using its domain. The actual server may be a path on the server or a machine in the domain.

 openid_server_property(+Server, +Property) is semidet

openid_server_property(+Server, -Property) is nondet

True if OpenID Server has Property.

See also

- openid_server_properties/2.

 current_user(?User)

True if User is a registered user.

 user_property(?User, ?Property) is nondet

user_property(+User, +Property) is semidet

True if Property is a defined property on User. In addition to properties explicitely stored with users, we define:

session(SessionID)

connection(LoginTime, Idle)

url(URL)

Generates reference to our own OpenID server for local login

openid(OpenID)

Refers to the official OpenID (possibly delegated)

openid_server(Server)

Refers to the OpenID server that validated the login

 validate_password(+User, +Password)

Validate the password for the given user and password.

 password_hash(+Password, ?Hash)

Generate a hash from a password or test a password against a hash. Uses crypt/2. The default hashing is Unix-compatible MD5.

 logged_on(-User) is semidet

True if User is the name of the currently logged in user.

 logged_on(-User, +Default) is det

Get the current user or unify User with Default. Typically, Default is anonymous.

 ensure_logged_on(-User)

Make sure we are logged in and return the current user. See openid_user/3 for details.

 authorized(+Action) is det

validate the current user is allowed to perform Action. Throws a permission error if this is not the case. Never fails.

Errors

- permission_error(http_location, access, Path)

 check_permission(+User, +Operation)

Validate that user is allowed to perform Operation.

Errors

- permission_error(http_location, access, Path)

 deny_all_users(+Term)

Deny some action to all users. See above.

 login(+User:atom) is det

Accept user as a user that has logged on into the current session.

 logout(+User) is det

Logout the specified user

Undocumented predicates

The following predicates are exported, but not or incorrectly documented.

 login(Arg1, Arg2)