Configuration
The integration of payment with QR code uses the object merchant_order, which is the identification of the order based on each reading performed on the QR.
In IPN notifications for in-person payments, the status field of the merchant_order will remain with the status opened until approved payments are identified and the payment amount is equal to or greater than the order total.
Within the order, in the payments object, you will find all payments made, whether approved or rejected. It is important to obtain the ID of payments with approved status in order to carry out chargebacks/refunds.
For each QR scan a different merchant_order is generated. Remember that if the customer does more than one scan, an order will be opened indefinitely and, to close the transaction, the merchant_order must have status = closed.
To receive notifications of events on your platform, you can previously configure a url to which Mercado Pago has access from the notification_url attribute when creating the order you wish to charge.
Notification flow
The payment confirmation process is divided in two parts: