Joomla logout with message - joomla

Question

I'm trying to modify the
'Token Interceptor' system plugin
by joomunited.com
The original plugin redirects on encountering an invalid token error using register_shutdown_function.
I'm trying to get it to:
Log the user out if they are logged in
Redirect to the login page with the invalid token message
Code:
$app = JFactory::getApplication();
if (!JFactory::getUser()->guest)
{
$app->logout();
}
$app->redirect('/index.php', JText::_('JINVALID_TOKEN'), 'warning');
I can successfully log the user out and redirect to the login page but the error message is not being displayed.
How can I retain the message after logging the user out?
i've also tried:
$app->enqueueMessage(JText::_('JINVALID_TOKEN'), 'warning');
but that didn't work either...

Answer 1

The solution I came up with was a variation of Alonzo Turner's 2nd post here.
The plugin redirects to the login page with a parameter passed in the url. The onAfterInitialise event then looks for this parameter and displays a message if it's found.
class PlgSystemTokeninterceptor extends JPlugin
{
public function __construct(&$subject, $config = array())
{
parent::__construct($subject, $config);
$app = JFactory::getApplication();
if (($app->isSite() && $this->params->get('use_frontend')) || ($app->isAdmin() && $this->params->get('use_backend')))
{
register_shutdown_function(array($this,'redirectToLogin'));
}
}
public function redirectToLogin()
{
$content = ob_get_contents();
if($content == JText::_('JINVALID_TOKEN') || $content == 'Invalid Token')
{
$app = JFactory::getApplication();
if (!JFactory::getUser()->guest)
{
$app->logout();
}
$app->redirect(JURI::base().'index.php?invalid_token=true');
return false;
}
}
function onAfterInitialise()
{
$app = JFactory::getApplication();
$invalid_token = $app->input->get('invalid_token', 'false');
if ($invalid_token == 'true')
{
$app->enqueueMessage(JText::_('JINVALID_TOKEN'), 'warning');
}
return true;
}
}

Answer 2

When you logout you destroy the session so you are not going to have the message any more.
This will get you a message on redirect.
$this->redirect = JUri::base() . 'index.php?option=com_users&view=login';
if (!JFactory::getUser()->guest && $app->input->getCmd('option') != 'com_users')
{
$app->enqueueMessage('message', 'warning');
//$app->logout();
$app->redirect($this->redirect);
}
This will not because the session is destroyed
$this->redirect = JUri::base() . 'index.php?option=com_users&view=login';
if (!JFactory::getUser()->guest && $app->input->getCmd('option') != 'com_users')
{
$app->enqueueMessage('message', 'warning');
$app->logout();
$app->redirect($this->redirect);
}
Not tested but
$app->logout()
echo '<div class="">'. JText::_('whatever you want') . '</div>';
$module = JModuleHelper::getModule('login');
$output = JModuleHelper::renderModule($module);
Something like that