In agile toolkit each object can register session variables. This is done to allow you to have multiple objects work indecently and not conflict.
Basic functions are:
$o->memorize( handle ,123);
$o->recall( handle );
$o->forget( handle );
If you intentionally wish to share data, then you can use
$o->api->memorize( my_global_var ,123);
Since you mentioned about User ID, then authorization object handles its own variables. Similarly it uses memorize/recall to manipulate auth data settings, but you can get the information like this:
$user_id = $o->api->auth->get( id );
When $auth->check() is performed, all fields returning by the query are saved. If you wish to add more fields, then perform
$auth->dq->field( extrainfo );
and this field will be selected by DSQL and stored in session too for further retrieval by $auth->get( extrainfo )
To create getUser function, typically you would define this in API:
function getUser(){
return $this->add( Model_User )->loadData($this->auth->get( id ));
}
and use $this->api->getUser()
to retrieve the data.