BookStack\Repos\PageRepo::getBySlug PHP Method

    public function getBySlug($slug, $bookId)
    {
        $page = $this->pageQuery()->where('slug', '=', $slug)->where('book_id', '=', $bookId)->first();
        if ($page === null) {
            throw new NotFoundException('Page not found');
        }
        return $page;
    }