public function getSchedulingObject($principalUri, $objectUri)
    {
        $stmt = $this->pdo->prepare('SELECT uri, calendardata, lastmodified, etag, size FROM '.$this->schedulingObjectTableName.' WHERE principaluri = ? AND uri = ?');
        $stmt->execute([$principalUri, $objectUri]);
        $row = $stmt->fetch(\PDO::FETCH_ASSOC);

        if (!$row) {
            return null;
        }

        return [
            'uri' => $row['uri'],
            'calendardata' => $row['calendardata'],
            'lastmodified' => $row['lastmodified'],
            'etag' => '"'.$row['etag'].'"',
            'size' => (int) $row['size'],
         ];
    }