Mělo by to stačit:
$dates = array();
// build an array with that data
foreach($events as $event)
$dates[] = (object)array(
'date' => date('Y/m/d'),
'title' => $event->title,
'desc' => sprintf('<a href="%s/index.php/events/get_event?id=%s">Details/Signups</a>', SITE_URL, $event->id),
);
?>
eventdates:
<?php print json_encode($dates); // print it as a json string ?>