Update Cart in Storefront

In this document, you'll learn how to update different details of a cart.

Update Cart's Region#

If a customer changes their region, you must update their cart to be associated with that region.

For example:

Code
1fetch(`http://localhost:9000/store/carts/${cartId}`, {2  credentials: "include",3  method: "POST",4  headers: {5    "Content-Type": "application/json",6    headers: {7      "x-publishable-api-key": process.env.NEXT_PUBLIC_MEDUSA_PUBLISHABLE_KEY || "temp",8    },9  },10  body: JSON.stringify({11    region_id: "new_id",12  }),13})14.then((res) => res.json())15.then(({ cart }) => {16  // use cart...17  console.log(cart)18})

The Update Cart API route accepts a region_id request body parameter, whose value is the new region to associate with the cart.

Set Cart's Customer#

You might need to change the cart's customer in two cases:

• You created the cart for the customer as a guest, then they logged-in, so you want to associate the cart with them as a registered customer.
• You're transfering the cart from one customer to another, which is useful in company setups, such as when implementing B2B commerce applicatons.

To set or change the cart's customer, send an authenticated POST request to the Set Cart's Customer API route:

Code
1fetch(`http://localhost:9000/store/carts/${cartId}/customer`, {2  credentials: "include",3  method: "POST",4  headers: {5    "Content-Type": "application/json",6    "x-publishable-api-key": process.env.NEXT_PUBLIC_MEDUSA_PUBLISHABLE_KEY || "temp",7  },8})9.then((res) => res.json())10.then(({ cart }) => {11  // use cart...12  console.log(cart)13})

To send an authenticated request, either use credentials: include if the customer is already authenticated with a cookie session, or pass the Authorization Bearer token in the request's header.

The cart is now associated with the logged-in customer.