Webhook

During registration the Merchant may provide an endpoint that will accept POST payload to utilize webhooks that will contain the status of the order.

Webhook is executed in the following scenarios:

Checkout is accepted and order is created (state: approved) - note that without 'approved' status, the /charge is not possible. This webhook will be sent only if immediate_capture is disabled.
Order is charged (state: completed). This webhook will be sent only if immediate_capture is enabled or for Pay in 3.
The customer is rejected on scoring (state: cancelled)
Scoring failed - unknown error (state: error)
Settled - Twisto has transfered funds (settled_date: <date>)
Refunded - order is refunded (refunded_amount: <Decimal>)
Cancel - order is canceled (state: cancelled)

The webhook will look like this:

{
    "checkout_id": ...,
    "total_amount": ...,
    "refunded_amount": ...,
    "created_date": "2019-08-24T14:15:22Z",
    "settled_date": "2019-08-26T14:15:22Z",
    "type": "standard",  # standard
    "state": "approved", # approved (scoring accepted), cancelled (scoring rejected or cancelled by merchant), error
    "external_id": ... # merchant transaction id
}