/** * Returns the book ID by a given ISBN */ function getBookIdByISBN($isbn_search) { require_once PATH_ACCESS . '/BookManager.php'; $bookManager = new BookManager(); try { $book_id = $bookManager->getBookIDByISBN($isbn_search); } catch (Exception $e) { $this->BookInterface->dieError($this->messages['error']['notFound'] . $e->getMessage()); } return $book_id['id']; }