hedera-web/rest/dms/invoice.php

<?php

use Vn\Web\Security;
use Vn\Web\Util;

class Invoice extends Vn\Web\RestRequest
{
	const PARAMS = ['invoice'];
	const SECURITY = Security::INVOKER;

	function run ($db)
	{
		$pdfPath = $db->getValueFromFile (__DIR__ .'/invoice',
			['invoice' => (int) $_GET['invoice']]);

		if (!$pdfPath)
			throw new Exception (s('Invoice id not found'));

		Util::printFile ($pdfPath);
	}
}