Bundles, add-ons and "frequently bought together"

Three sales modules: bundles, product add-ons and “frequently bought together” (FBT). Each works independently.

Requirements

Polski PRO requires: Polski (free) v1.6.0+, WordPress 6.4+, WooCommerce 8.0+, PHP 8.1+

Product bundles

The bundles module allows creating configurable product sets with a shared discount. The customer purchases a bundle as a single product, and the individual components are visible in the order details.

Configuration

Enable Product bundles in Polski > Modules (module id product_bundles).

Setting	Default value	Description
Enable bundles	No	Activates the bundle functionality
Discount type	Percent	percent (percentage) or fixed (fixed amount)
Default discount	10%	Discount applied to new bundles
Show savings	Yes	Displays the savings amount to the customer

Creating a bundle

1. Go to Products > Add New
2. In the Product data section, select the “Polski PRO Bundle” type
3. In the Bundle components tab, add products
4. Set the quantity for each component
5. Configure the discount (overrides the default)

Discount calculation

The bundle price is calculated automatically:

Cena pakietu = Suma cen składników - Rabat

Przykład (rabat 15%):
Produkt A: 100 zł x 1 = 100 zł
Produkt B:  50 zł x 2 = 100 zł
Suma:                    200 zł
Rabat (15%):              30 zł
Cena pakietu:            170 zł

If a bundle component is on sale, the sale price is used in the calculations.

Bundle shortcode

[polski_bundle product_id="456" show_savings="yes" layout="grid"]

Parameter	Required	Description
product_id	Yes	Bundle product ID
show_savings	No	Display savings amount (yes/no)
layout	No	Layout: grid, list, compact

Bundle hooks

/**
 * Filtruje obliczoną cenę pakietu.
 *
 * @param float $bundle_price Obliczona cena pakietu
 * @param array $items        Składniki pakietu z cenami
 * @param float $discount     Wartość rabatu
 */
apply_filters('polski_pro/bundles/price', float $bundle_price, array $items, float $discount): float;

Example - minimum bundle price:

add_filter('polski_pro/bundles/price', function (float $bundle_price, array $items, float $discount): float {
    $minimum_price = 49.99;
    return max($bundle_price, $minimum_price);
}, 10, 3);

/**
 * Akcja wywoływana po dodaniu pakietu do koszyka.
 *
 * @param string $cart_item_key Klucz pozycji w koszyku
 * @param int    $bundle_id    ID produktu-pakietu
 * @param array  $items        Składniki pakietu
 */
do_action('polski_pro/bundles/added_to_cart', string $cart_item_key, int $bundle_id, array $items);

Product add-ons

The add-ons module allows displaying optional upsell products directly on the product page. The customer can select additional products and purchase them with a single click alongside the main product.

Configuration

Add-ons need no switching on. The service boots with Polski PRO and add-ons are configured per product.

Setting	Default value	Description
Enable add-ons	No	Activates the add-on functionality
Display position	After cart button	Where to display the add-ons section
Section heading	“Dodaj do zamówienia”	Heading text above the add-on list
Maximum count	5	Limit of add-ons displayed per product

Assigning add-ons

Add-ons are configured in the product editor, in the Polski PRO Add-ons tab:

1. Click “Add add-on”
2. Select a product from the catalog
3. Set the add-on price (defaults to the product price)
4. Optionally set a promotional add-on price
5. Set the display order

Add-ons can have a different price than the source product - this allows offering special “with product” pricing.

Selection validation

The module validates:

• Stock availability of each selected add-on
• Price correctness (whether they were not modified client-side)
• Quantity limits

Add-on hooks

/**
 * Filtruje listę dodatków dla produktu.
 *
 * @param array       $addons  Tablica dodatków z cenami
 * @param \WC_Product $product Produkt główny
 */
apply_filters('polski_pro/addons/items', array $addons, \WC_Product $product): array;

Example - filtering add-ons based on user role:

add_filter('polski_pro/addons/items', function (array $addons, \WC_Product $product): array {
    if (current_user_can('wholesale_customer')) {
        foreach ($addons as &$addon) {
            $addon['price'] = $addon['price'] * 0.8; // 20% rabatu hurtowego
        }
    }
    return $addons;
}, 10, 2);

Frequently bought together

The recommendations module displays products most frequently purchased together with the viewed product, with the ability to add multiple products to the cart with a single click.

Configuration

Enable Frequently bought together in Polski > Modules (module id frequently_bought_together).

Setting	Default value	Description
Enable module	No	Activates recommendations
Data source	Manual	manual or auto (based on order history)
Product limit	3	Maximum number of recommended products
Section heading	“Często kupowane razem”	Section heading text
Position	Below short description	Where to display the section

Manual assignment

In the product editor, Frequently bought together tab:

1. Search and add related products
2. Set the display order
3. Optionally set a discount for purchasing together

Automatic recommendations

When the data source is set to auto, the module analyzes order history and identifies products most frequently purchased together. The analysis runs once daily via WP-Cron.

Adding to cart

The “Frequently bought together” section displays:

• Checkboxes next to each recommended product
• Thumbnails and product names
• Individual product prices
• Total price of selected products
• “Add all to cart” button

The customer checks the desired products and adds them with a single click. All products are added to the cart as separate items.

Shortcode

[polski_fbt product_id="789" limit="4" show_prices="yes"]

Parameter	Required	Description
product_id	No	Main product ID (defaults to current)
limit	No	Maximum number of recommendations
show_prices	No	Display prices (yes/no)

FBT hooks

/**
 * Filtruje listę rekomendowanych produktów.
 *
 * @param array $product_ids Tablica ID rekomendowanych produktów
 * @param int   $product_id  ID produktu głównego
 * @param string $source     Źródło: 'manual' lub 'auto'
 */
apply_filters('polski_pro/fbt/products', array $product_ids, int $product_id, string $source): array;

Example - excluding products from a specific category:

add_filter('polski_pro/fbt/products', function (array $product_ids, int $product_id, string $source): array {
    $excluded_category_id = 42;
    return array_filter($product_ids, function (int $id) use ($excluded_category_id): bool {
        return ! has_term($excluded_category_id, 'product_cat', $id);
    });
}, 10, 3);

Module interplay

All three modules can work simultaneously on the same product:

• A bundle with assigned add-ons and a frequently bought together section
• Bundle components can have their own add-ons
• FBT recommendations can point to bundles

The display order on the product page is configurable via WooCommerce hook priorities.

Troubleshooting

Bundle price does not update after changing component prices The bundle price is calculated dynamically. Clear the Object Cache and WooCommerce transients.

Add-ons do not display on the product page Check if the theme supports the woocommerce_after_add_to_cart_button hook. Some custom themes skip standard WooCommerce hooks.

Automatic recommendations are empty The module needs historical data - automatic recommendations appear after collecting a sufficient number of orders. Check if the polski_pro_fbt_analyze WP-Cron task is scheduled.

Next steps

• Report issues: GitHub Issues
• Related modules: Pre-orders, Catalog mode

This page is for informational purposes only and does not constitute legal advice. Consult a lawyer before implementation. Polski for WooCommerce is open source software (GPLv2) provided without warranty.