Documentation

A ServerError that asks the client to authenticate via Basic Authentication, should be invoked by an application whenever appropriate. The argument is the realm.

A type holding the configuration for Basic Authentication. It is defined as a type family with no arguments, so that it can be instantiated to whatever type you need to authenticate your users (use type instance BasicAuthCfg = ...).

Note that the instantiation is application-wide, i.e. there can be only one instance. As a consequence, it should not be instantiated in a library.

Basic Authentication expects an element of type BasicAuthCfg to be in the Context; that element is then passed automatically to the instance of FromBasicAuthData together with the authentication data obtained from the client.

If you do not need a configuration for Basic Authentication, you can use just BasicAuthCfg = (), and recall to also add () to the Context. A basic but more interesting example is to take as BasicAuthCfg a list of authorised username/password pairs:

deriving instance Eq BasicAuthData
type instance BasicAuthCfg = [BasicAuthData]
instance FromBasicAuthData User where
  fromBasicAuthData authData authCfg =
    if elem authData authCfg then ...