[browser-payment-api] How are web-based payment apps supported? (#39)

Migrating issue from https://github.com/w3c/webpayments/issues/16

How do we support Web-based payment instruments? These instruments require a user to:

1. Start on the merchant website
2. Click buy
3. Select the web-based instrument
4. Navigate to a 3rd party website to approve the transaction
5. Return to the merchant website with a token, approval code, or other proof that the transaction has been approved.

I suggest that we support web-based payment instruments and local payment instruments using the same mechanism. There is a URL that is used to invoke the payment instrument. Local Android payment instruments would use an Intent URL (or something similar). Cloud-based instruments would use an HTTP-based URL. Both would have a callback URL (either another Intent URL or an HTTP-based URL).

I admit that this proposal is a bit hand wavy as I do not have a great deal of experience routing messages from a browser to an intent-based URL and back to the browser.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/browser-payment-api/issues/39