How To Set Sale In Woocommerce With Code

How to Set Sale Prices in WooCommerce with Code: A Beginner’s Guide

Want to supercharge your WooCommerce sales with targeted discounts? While the WooCommerce interface offers a simple way to set sale prices, using code provides unparalleled flexibility and automation. This guide is designed for WooCommerce newbies who want to dive into the world of programmatic sale price management. We’ll cover the basics, real-life examples, and reasoning behind each step.

Why Use Code to Set Sale Prices?

Imagine you’re running a seasonal promotion, like a “Back to School” sale, or offering a special discount for a particular category. Manually updating sale prices for hundreds of products in WooCommerce can be a time-consuming and error-prone task. This is where code comes to the rescue! Using code allows you to:

Automate sales based on specific conditions: Schedule sales to start and end automatically.
Apply targeted discounts: Offer discounts based on product categories, tags, attributes, or even custom fields.
Implement complex pricing strategies: Calculate discounts dynamically based on order value, customer role, or other factors.
Integrate with other plugins and systems: Connect your sales strategy with marketing automation tools or other external services.
Avoid manual errors: Reduce the risk of human error when setting or removing sale prices.

Think of it this way: Using the WooCommerce admin interface is like manually adding a coupon to each product. Using code is like creating a powerful program that automatically applies coupons based on your rules!

The Basics: WooCommerce Sale Price Functions

WooCommerce provides several handy functions to manage product prices, including sale prices. Let’s look at the core functions you’ll be using:

`update_post_meta($product_id, ‘_regular_price’, $regular_price);` : This function updates the regular price of a product. It’s essential to have a regular price before setting a sale price.
`update_post_meta($product_id, ‘_sale_price’, $sale_price);` : This function sets the sale price of a product. This is the price customers will actually pay during the sale.
`update_post_meta($product_id, ‘_price’, $price);` : This function sets the actual price displayed to the customer. When a sale price is active, this function will reflect the sale price.
`update_post_meta($product_id, ‘_sale_price_dates_from’, $from);` : This function sets the start date for the sale (Unix timestamp).
`update_post_meta($product_id, ‘_sale_price_dates_to’, $to);` : This function sets the end date for the sale (Unix timestamp).
`delete_post_meta($product_id, ‘_sale_price’);` : This function removes the sale price.

Important Note: These functions directly interact with the WordPress database. Make sure to test your code thoroughly on a staging environment before applying it to your live site!

Example 1: Setting a Sale Price for a Specific Product

Let’s say you want to put a specific product (Product ID: 123) on sale for $20. Here’s how you can do it with code:

<?php
/**
Sets a sale price for a specific product.
* @param int   $product_id The ID of the product.
@param float $sale_price The sale price to set.
*/
function set_product_sale_price( $product_id, $sale_price ) {
// Get the product object.
$product = wc_get_product( $product_id );

if ( $product ) {

//Ensure regular price is set before sale price.

$regular_price = $product->get_regular_price();

if (empty($regular_price) || $regular_price == 0){

$regular_price = 50; //Default value if regular price isn’t present

update_post_meta( $product_id, ‘_regular_price’, $regular_price );

}

// Update the sale price.

update_post_meta( $product_id, ‘_sale_price’, $sale_price );

// Update the price (important for displaying the correct price).

update_post_meta( $product_id, ‘_price’, $sale_price );

// Clear the product cache. Important to see the change immediately

wc_delete_product_transients( $product_id );

error_log(“Set sale price for product ” . $product_id . ” to ” . $sale_price);

} else {

error_log( ‘Product with ID ‘ . $product_id . ‘ not found.’ );

}

// Example usage: Set product with ID 123 on sale for $20.

set_product_sale_price( 123, 20.00 );

Explanation:

1. `set_product_sale_price( $product_id, $sale_price )`: Defines a function that takes the product ID and sale price as arguments.

2. `wc_get_product( $product_id )`: Retrieves the WooCommerce product object based on its ID. This allows you to get additional information about the product, like its regular price.

3. `if ( $product )`: Ensures that the product exists before attempting to modify its price. Error handling is *crucial*!

4. `update_post_meta(…)`: The core function that updates the product’s metadata (price information) in the database. Note the use of `_` before the meta keys (`_regular_price`, `_sale_price`, `_price`). This signifies that these are protected meta keys used internally by WooCommerce.

5. `wc_delete_product_transients( $product_id )`: This is a very important line. WooCommerce often caches product data for performance reasons. By deleting the transients, you force WooCommerce to recalculate and display the new sale price immediately. Without this, you might not see the changes right away.

6. `error_log(…)`: Adds error logging to help you debug your code. Using WordPress’s error log helps identify and fix issues.

7. Example usage: The last line demonstrates how to call the function to set the sale price for a specific product.

Where to put this code?

For a one-time execution like this example, you can temporarily place this code in your theme’s `functions.php` file. *Remember to remove it after you run it!* Alternatively, you can use a plugin like “Code Snippets” to execute custom code snippets without modifying your theme files. Never directly edit core WooCommerce files!

Example 2: Scheduling a Sale for a Category of Products

Let’s take things up a notch. Suppose you want to run a “Summer Sale” on all products in the “T-Shirts” category. The sale should run from July 1st, 2024 to July 31st, 2024, with a 20% discount.

<?php
/**
Sets a scheduled sale for a specific product category.
* @param string $category_slug The slug of the product category.
@param float  $discount_percentage The percentage discount (e.g., 0.20 for 20%).
@param string $start_date The start date in YYYY-MM-DD format.
@param string $end_date The end date in YYYY-MM-DD format.
*/
function schedule_category_sale( $category_slug, $discount_percentage, $start_date, $end_date ) {
$args = array(
'post_type'      => 'product',
'posts_per_page' => -1, // Get all products
'tax_query'      => array(
array(
'taxonomy' => 'product_cat',
'field'    => 'slug',
'terms'    => $category_slug,
),
),
);

$products = new WP_Query( $args );

if ( $products->have_posts() ) {

while ( $products->have_posts() ) {

$products->the_post();

$product_id = get_the_ID();

$product = wc_get_product( $product_id );

if ( $product ) {

$regular_price = $product->get_regular_price();

//Calculate the sale price

$sale_price = $regular_price – ($regular_price * $discount_percentage);

$sale_price = round($sale_price, 2); //Round to 2 decimal places

// Convert dates to timestamps

$start_timestamp = strtotime( $start_date . ‘ 00:00:00’ );

$end_timestamp = strtotime( $end_date . ‘ 23:59:59’ );

// Update sale price and dates

update_post_meta( $product_id, ‘_sale_price’, $sale_price );

update_post_meta( $product_id, ‘_price’, $sale_price );

update_post_meta( $product_id, ‘_sale_price_dates_from’, $start_timestamp );

update_post_meta( $product_id, ‘_sale_price_dates_to’, $end_timestamp );

// Clear product cache

wc_delete_product_transients( $product_id );

error_log( “Scheduled sale for product ” . $product_id . ” in category ” . $category_slug );

}

wp_reset_postdata(); // Reset the global post data after the loop.

} else {

error_log( “No products found in category ” . $category_slug );

}

// Example usage: Schedule a 20% discount for the “t-shirts” category

schedule_category_sale( ‘t-shirts’, 0.20, ‘2024-07-01’, ‘2024-07-31’ );

Key Improvements and Explanation:

1. Category Targeting: Uses `WP_Query` with a `tax_query` to select only products belonging to the specified category.

2. Discount Percentage: Calculates the sale price based on the regular price and a discount percentage. Rounding is added to avoid prices with more than two decimal places.

3. Date Scheduling: Converts the start and end dates to Unix timestamps using `strtotime()` and then sets the `_sale_price_dates_from` and `_sale_price_dates_to` meta fields. Important: WooCommerce uses Unix timestamps for sale date management.

4. `wp_reset_postdata()`: Crucial to call this after your `WP_Query` loop to restore the original WordPress global post data. Failing to do so can cause issues on other parts of your site.

5. Clear Product Cache: As before, `wc_delete_product_transients( $product_id )` clears the cache to ensure changes are immediately visible.

6. Date Formatting: Ensures that the start and end dates are correctly formatted and that the end date includes the full day’s time.

7. Error logging: Logs information about the products that are processed.

8. Sanitization (Important!) In a real-world application, you would want to sanitize user inputs such as category slug, discount percentage, start and end date using WordPress functions like `sanitize_text_field` and `floatval` for security.

Where to place and run this code:

Again, for a one-time sale scheduling, you can temporarily place this code in `functions.php` or use the “Code Snippets” plugin. Remove the code once the sale is scheduled to avoid unintended consequences.

Important Considerations:

Performance: If you have a very large number of products, looping through them all in one go might impact performance. Consider using a cron job or a more efficient method for large catalogs.
Error Handling: Always include robust error handling to catch potential issues, such as invalid product IDs or incorrect date formats.
Security: If you’re taking user input (e.g., from a form) to determine the sale parameters, be sure to sanitize the input to prevent security vulnerabilities.
Themes and Plugins: Be aware that some themes or plugins might override the default WooCommerce pricing behavior. Test your code thoroughly to ensure compatibility.
Testing: Always test your code on a staging environment before deploying it to your live site! Use dummy products and sample data to verify that your sales are being applied correctly.

Conclusion

Setting sale prices programmatically in WooCommerce opens up a world of possibilities for automating your sales strategies. While this guide provides a starting point, remember to always test your code thoroughly and consider the performance implications for larger product catalogs. With a little practice, you’ll be able to create powerful and efficient WooCommerce sales solutions!