Sarathlal N

How to Update Product Quantity in WooCommerce Using Custom Code

Managing inventory is essential for any online store. WooCommerce, a popular e-commerce platform, allows you to update product quantities manually. However, there are times when you might need to update these quantities automatically through custom code. This guide will show you how to update product quantities in WooCommerce programmatically using simple, custom code.

Why Update Product Quantities Programmatically?

Updating product quantities programmatically can be beneficial in several scenarios, such as:

Automatically adjusting stock levels based on external inventory systems.
Setting default stock quantities for certain products upon specific triggers.
Implementing complex stock management rules that WooCommerce does not support by default.

Using WooCommerce Hooks and Functions

WooCommerce provides hooks and functions that make it easy to interact with product data. In this tutorial, we will use the woocommerce_thankyou hook to update product quantities when an order is placed.

Step-by-Step Guide

1. Adding Custom Code to Your Child Theme’s `functions.php`

To update product quantities programmatically, you need to add custom code to your child theme’s functions.php file. Here is an example:

// Function to update product stock quantity
function update_product_stock_quantity($product_id, $quantity) {
    // Get the product object
    $product = wc_get_product($product_id);
    
    // Check if the product exists
    if ($product) {
        // Update the stock quantity
        $product->set_stock_quantity($quantity);
        
        // Save the product to update the stock quantity in the database
        $product->save();
        
        // Optionally, you can set the stock status to 'instock' or 'outofstock'
        // $product->set_stock_status('instock');
        // $product->save();
    }
}

// Hook into WooCommerce to update product stock quantity when an order is placed
add_action('woocommerce_thankyou', 'custom_update_product_stock_on_order');

function custom_update_product_stock_on_order($order_id) {
    // Get the order object
    $order = wc_get_order($order_id);
    
    // Loop through the order items
    foreach ($order->get_items() as $item_id => $item) {
        // Get the product ID from the order item
        $product_id = $item->get_product_id();
        
        // Set the new quantity (example: setting it to 100)
        $new_quantity = 100;
        
        // Update the product stock quantity
        update_product_stock_quantity($product_id, $new_quantity);
    }
}

2. Explanation of the Code

update_product_stock_quantity($product_id, $quantity) Function: This function takes two parameters: the product ID and the new quantity. It retrieves the product object using wc_get_product, updates the stock quantity, and saves the changes.
woocommerce_thankyou Hook: The custom_update_product_stock_on_order function is hooked to the woocommerce_thankyou action, which runs after an order is placed. It loops through the items in the order and updates the stock quantity for each product.

3. Customization

Product ID and Quantity: Customize the product ID and the new quantity according to your needs. In this example, the product quantity is set to 100 for each product in the order.
Stock Status: Optionally update the stock status using $product->set_stock_status('instock') or $product->set_stock_status('outofstock').

Your Questions / Comments

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