---
title: "Sitewide Discount Developer Reference: Functions, Hooks and Shortcode"
description: Helper functions, filter, action, shortcode and price hooks in Sitewide Discount for WooCommerce, with code examples.
url: "https://wpfactory.com/docs/sitewide-discount-developers/"
updated: "2026-10-05"
category: Developers
---

# Sitewide Discount Developer Reference: Functions, Hooks and Shortcode

This developer reference for [Sitewide Discount for WooCommerce](https://wpfactory.com/item/global-shop-discount-for-woocommerce/) lists the helper functions, filter, action and shortcode you can use in themes and custom code, plus the WooCommerce price hooks the plugin uses. Settings live at **WPFactory > Global Shop Discount**. Everything here is in both the free and Pro versions.

## Helper functions

| Function | Returns |
| --- | --- |
| `alg_wc_gsd_is_discount_product( $product )` | `true` if a discount group changes this product's price, otherwise `false`. |
| `alg_wc_gsd_get_product_discount_groups( $product )` | An array of the group numbers that apply to the product. With **Stop on first matching discount group** on, this holds at most one group. |
| `alg_wc_gsd_get_product_ids( $product_query_args = array( 'limit' => -1 ), $incl_on_sale = true, $use_transient = false )` | An array of product IDs that are discounted by the plugin. `$product_query_args` is passed to `wc_get_products()`. With `$incl_on_sale` true, products already on sale are included too. With `$use_transient` true, results are cached for 24 hours. |

Each function takes a `WC_Product` object where a product is expected, and returns `false` if the plugin is not loaded. The discount engine only loads on the storefront unless **Apply discounts in backend** is enabled, so call these functions from front-end code.

### Example: add a badge to discounted products

```
add_action( 'woocommerce_before_shop_loop_item_title', function () {
	global $product;
	if ( function_exists( 'alg_wc_gsd_is_discount_product' ) && alg_wc_gsd_is_discount_product( $product ) ) {
		echo '<span class="my-sitewide-badge">Sitewide sale</span>';
	}
} );
```

## Shortcode

`[alg_wc_gsd_products]` outputs a WooCommerce `[products]` grid of all products currently on sale.

| Attribute | Description | Default |
| --- | --- | --- |
| `use_transient` | Cache the on-sale product IDs in the `alg_wc_gsd_products_onsale` transient for 24 hours. | Off |
| `on_empty` | Output when no products are found. | Empty |
| Other attributes | Passed through to `[products]`, with `ids` set to the found products. | None |

## Filter

| Filter | Parameters | Use |
| --- | --- | --- |
| `alg_wc_global_shop_discount_shortcode_product_ids` | `$product_ids_on_sale` (array), `$atts` (shortcode attributes) | Change the product IDs the `[alg_wc_gsd_products]` shortcode displays. Runs before the result is cached. |

```
add_filter( 'alg_wc_global_shop_discount_shortcode_product_ids', function ( $ids, $atts ) {
	return array_diff( $ids, array( 123 ) ); // Hide product 123.
}, 10, 2 );
```

## Action

| Action | When it fires |
| --- | --- |
| `alg_wc_global_shop_discount_settings_saved` | After the plugin settings are saved (the Tools run on this action). |

## WooCommerce hooks the plugin filters

Prices are changed at priority `PHP_INT_MAX` on these filters, so the discount is applied after most other pricing code:

- `woocommerce_product_get_price`, `woocommerce_product_get_sale_price`, `woocommerce_product_get_regular_price` (the regular price is passed through unchanged)
- `woocommerce_product_variation_get_price`, `woocommerce_product_variation_get_sale_price`, `woocommerce_product_variation_get_regular_price`
- `woocommerce_variation_prices_price`, `woocommerce_variation_prices_sale_price`, `woocommerce_variation_prices_regular_price`
- `woocommerce_get_variation_prices_hash` (adds the group settings to the variation price cache key)
- `woocommerce_get_price_including_tax`, `woocommerce_get_price_excluding_tax` (grouped products)

If your code needs the undiscounted price, read the stored meta (for example `_price`) or use `$product->get_price( 'edit' )`, which bypasses these filters.

## Stored data

- Settings are stored as WordPress options prefixed `alg_wc_global_shop_discount_`. Group options are arrays keyed by group number. See the [settings reference](https://wpfactory.com/docs/sitewide-discount-settings/) for every option ID.
- Transients: `alg_wc_gsd_products_onsale` (shortcode) and `alg_wc_gsd_products_{md5}` (from `alg_wc_gsd_get_product_ids()` with caching on).
- The plugin does not write product prices unless you run **Tools > Save prices in DB for all products**.

Need a hand? Our team answers every ticket on the [Sitewide Discount support forum](https://wpfactory.com/support/item/global-shop-discount-for-woocommerce/).

Related articles

- [Sitewide Discount Troubleshooting: Discount Not Showing or Applied Twice](https://wpfactory.com/docs/sitewide-discount-troubleshooting/)
- [Getting Started with Sitewide Discount for WooCommerce](https://wpfactory.com/docs/sitewide-discount-getting-started/)
- [How to Give a Discount to Specific User Roles or Customers in WooCommerce](https://wpfactory.com/docs/sitewide-discount-user-roles/)
- [How to Discount Specific Categories or Products in WooCommerce](https://wpfactory.com/docs/sitewide-discount-categories-products/)
- [How to Schedule a Sitewide Sale in WooCommerce](https://wpfactory.com/docs/sitewide-discount-schedule-sale/)