Pre-populate customer billing/shipping data in Klarna/Kustom Checkout session

[AndersEbdrup]

When using the Klarna/Kustom payment gateway integration in DynamicWeb, customers who are already logged in or have entered their details in the DynamicWeb checkout are required to re-enter their billing and shipping information inside the Klarna/Kustom iframe. This creates unnecessary friction and increases the risk of cart abandonment.

Desired behavior
DynamicWeb should pass the customer's existing billing and shipping address data when creating the Klarna/Kustom Checkout session, so the Klarna iframe is pre-populated with the customer's details.

Klarna API support
The Klarna/Kustom API already supports this. The billing_address and shipping_address objects can be included in the session creation payload:
json{
"billing_address": {
"given_name": "Anders",
"family_name": "Ebdrup",
"email": "anders@example.com",
"phone": "+4512345678",
"street_address": "Eksempelgade 1",
"postal_code": "8000",
"city": "Aarhus",
"country": "DK"
}
}

Use case
Logged-in customers should not have to re-enter information already present in their profile
Guest checkout customers who have filled in their details in DynamicWeb's checkout flow should have those details forwarded to Klarna