Stripe should support handlePaymentNotification

[jmcclelland]

In 4.7, CiviCRM payment processors that have a handlePaymentNotification method can have their webhooks accessed via /civicrm/payment/ipn/ID - where ID is the payment processor id.

This allows us to properly handle payments from two different Stripe payment processors configured on the site, which is not possible now.

[h-c-c]

Aside from the obvious difference in URL, how is how is this functionally different from the multiple Stripe account support that @agh1 contributed?

To my knowledge, none of the challenges surrounding multiple Stripe accounts have to do with the webhook code at this time.

[jmcclelland]

Functionally it's the same, however, by supporting handlePaymentNotification we will provide support for the new standard way to distinguish between payment processors - so if users follow the general CiviCRM directions it will work with Stripe.

Additionally, CiviCRM has an IPN base class. To keep up with CiviCRM Core development, we should probably implement that Base class rather than handle web hooks via a class the extends CRM_Core_Page

[jmcclelland]

And create unit tests to ensure that our IPN code continues to work.

I'm happy to work on this ticket.

[jmcclelland]

I've created unit tests via #224

[jmcclelland]

Tests are created - and this pull requests does it all: #225 and passes all tests.

Note: this has no impact by default - it will only be used if people switch to the standard CiviCRM IPN handling URL (civicrm/payment/ipn/N).