[w3c/webpayments] How can a Web Based Payment App cancel the payment flow? (#128)

I've experimented a bit with implementing a web based payment app, by making a simple web app that encapsulates a Visa Checkout flow ([as described here](https://arch.developer.visa.com/vme/merchant/documents/Getting_Started_With_Visa_Checkout/Quick_Start_Tutorial.html)). The Visa Checkout flow consists of a series of pages, which all have an X in the upper right corner for canceling out of the flow. See screenshot:

![visacheckout](https://cloud.githubusercontent.com/assets/12935345/14810489/8a32f2e2-0b93-11e6-88ae-f4ee85264ec9.png)

If the user presses that X, I need to send a "cancel" message back to the user agent, so that it can close the browser window and return to a suitable step in the web payments flow.

What would be the best way of doing this? A separate javascript api? Or calling submitPaymentResponse with a response that indicates an error/cancellation? Or Ballista IPC as mentioned in the issue box under payment-apps:6.3.1.1.1?

---
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/w3c/webpayments/issues/128