public function products_by_vendor($slug)
 {
     $page = !empty($_GET['page']) ? $_GET['page'] : 1;
     $per_page = 16;
     $products_total = Product::findByVendorSlug(null, $slug);
     $products = Product::findByVendorSlug(array('limit' => $per_page, 'offset' => ($page - 1) * $per_page), $slug);
     return $this->_product_grid($products, $products_total, $page, $per_page);
 }