Intro
Khaime has a few read-only calls that answer “what will the customer pay?” at different points in checkout. Used together, they let your UI show the right price, fee and total at every step — and the charge always matches what the customer saw.The calls, in checkout order
You don’t need every call. A single-page checkout with all details on one form can go straight from Get Product to Preview Payment.
Hows
Keep four things the same
- One currency everywhere. Send the customer’s chosen code to Get Product, Get Fee Breakdown, Preview Payment and the intent.
- Same body for preview and intent. Preview Payment takes exactly the body you’ll send to Create Product Payment Intent, so build it once and send it twice.
- Show the fee when the customer pays it. When
customer_pays_feesistrue, show the transaction fee as its own line. See Fees. - The intent is the charge. The breakdown and preview are for display. What the customer pays is the intent’s
amount.
Example: review step, then pay
Why nots
- Don’t compute fees or totals yourself. Fees depend on currency, gateway, country and the merchant’s settings, and they change. Read them from Khaime.
- Preview Payment needs the full cart. It validates everything the intent does, including required custom fields, so call it once those are filled in. Use Get Fee Breakdown before that.
- A preview isn’t a reservation. Rates can move between preview and payment. If the customer waits a long time, preview again.
