Use Discounts in Checkout
In this document, learn how to use discounts during checkout on the storefront.
You can check out the Discounts Architecture documentation to learn more about how discounts work.
Overview
Customers can use discounts during checkout to benefit from promotions that the merchant provides. Discounts are added to a cart using its unique code.
In this document, you’ll learn how to add a discount to a cart, how to display details related to the discount, and how to remove a discount from a cart.
Scenario
You want to implement discount functionality in your store to allow customers to apply discount codes to their cart and remove them from the cart. You also want to display the discount details for the customer.
Prerequisites
Medusa Components
It's assumed that you already have a Medusa backend installed and set up. If not, you can follow the quickstart guide to get started.
It is also assumed you already have a storefront set up. It can be a custom storefront or one of Medusa’s storefronts. If you don’t have a storefront set up, you can install the Next.js Starter Template.
JS Client
This guide includes code snippets to send requests to your Medusa backend using Medusa’s JS Client, among other methods.
If you follow the JS Client code blocks, it’s assumed you already have Medusa’s JS Client installed and have created an instance of the client.
Medusa React
This guide also includes code snippets to send requests to your Medusa backend using Medusa React, among other methods.
If you follow the Medusa React code blocks, it's assumed you already have Medusa React installed and have used MedusaProvider higher in your component tree.
It's also assumed you already have used CartProvider higher in your component tree.
Previous Steps
This document assumes you’ve already taken care of the add-to-cart flow. So, you should have a cart created for the customer with at least one product in it.
You can learn how to implement the cart flow using this documentation.
Add Discount to Cart
The customer can enter a discount code during the checkout flow to benefit from a promotion.
You can add a discount to a customer’s cart by sending the Update Cart request:
fetch(`<BACKEND_URL>/store/carts/${cartId}`, {
method: "POST",
credentials: "include",
body: JSON.stringify({
discounts: [
{
code,
},
],
}),
headers: {
"Content-Type": "application/json",
},
})
.then((response) => response.json())
.then(({ cart }) => {
console.log(cart.discounts)
})
.catch((e) => {
// display an error to the customer
alert("Discount is invalid")
})
This request requires the customer’s cart ID as a path parameter. In the body of the request, you can update many cart-related details, including adding discounts by passing the discounts
field. It is an array of objects, with each object having a property code
with its value being the discount’s unique code.
Customers can add more than one discount to their cart, however, only one non-free shipping discount is allowed per cart.
If the discount is applied successfully, the entire cart object will be returned. You can access the discounts applied on the cart in the cart.discounts
array.
In case the customer enters an invalid discount or the discount cannot be applied to the cart because it doesn’t meet its conditions, the request will return an error. You can handle the error in the catch
method.
Display Discount Details
After the customer enters a discount code and it is applied to the cart, you can display the discount details to the customer. This shows the customer how much they benefited from the discount.
The previous request returns the full cart object with different fields that can be used to display the discount details depending on the discount type.
Display Discount Information
In the returned cart
object, all discounts applied can be found in the discounts
array. The following properties can be used to display the discount information:
{
"discounts": [
{
"code": "TEST",
"is_dynamic": false,
"starts_at": "2022-12-01T15:09:21.149Z",
"ends_at": null,
"usage_limit": null,
"usage_count": 0,
"rule": {
"description": "percentage discount",
"type": "percentage",
"value": 20,
"allocation": "total",
"conditions": [
//...
],
//...
},
//...
}
],
//...
}
- The
code
property is the code of the discount. This is the code that the customer enters to apply the discount. - The
starts_at
andends_at
indicate the start and expiry dates of the discount. If there’s no end date, theends_at
property will be null. - The
usage_limit
property indicates if there is any usage limit set on the discount. Theusage_count
property indicates how many times this discount has been used. - The
rule
property includes details related to the type of discount, its value, and its conditions if there are any.