protected function casUser()
 {
     $cas_host = \Config::get('app.cas_host');
     $cas_context = \Config::get('app.cas_context');
     $cas_port = \Config::get('app.cas_port');
     \phpCAS::setDebug();
     \phpCAS::client(CAS_VERSION_2_0, $cas_host, $cas_port, $cas_context);
     \phpCAS::setNoCasServerValidation();
     if (\phpCAS::isAuthenticated()) {
         $attributes = array('id' => \phpCAS::getUser(), 'name' => \phpCAS::getUser());
         return new GenericUser($attributes);
     } else {
         \phpCAS::setServerURL(\Config::get('app.url'));
         \phpCAS::forceAuthentication();
     }
     return null;
 }