Carew\Event\Listener\Metadata\Optimization::onPost PHP Method

    private function onPost(Document $document)
    {
        list($year, $month, $day, $slug) = explode('-', $document->getFile()->getBasename('.md'), 4);
        $document->addMetadatas(array('date' => new \DateTime("{$year}-{$month}-{$day}")));
        $metadatas = $document->getMetadatas();
        if (!isset($metadatas['permalink'])) {
            $path = strtr($this->permalinkFormat, array('%year%' => $year, '%month%' => $month, '%day%' => $day, '%slug%' => $slug));
            $document->setPath($this->path->generatePath($path));
        }
    }