/**
* @param Event $event
* @return string
* @throws UnknownEventException
*/
private function serizlize(Event $event)
{
if ($event instanceof CustomerPlacedOrder) {
return json_encode(['name' => Events::CUSTOMER_PLACED_ORDER, 'order_id' => $event->orderId(), 'date' => $event->date()->format('Y-m-d H:i:s')]);
}
throw UnknownEventException::unsupported(get_class($event));
}