The transaction notifications sent by PayPal will slightly change. We need to adapt our application to be able to process them. Please refer to the [investigation documentation](https://docs.google.com/document/d/1UzOKLG9mk9kWO3wRKZKGBMevnVJc3qdVYNNY9nb-u8o/edit#heading=h.qeqkx356gbyr) for more details.
**Acceptance Criteria**
- Payment notifications for one-time payments can be processed by our application.
- Payment notifications for recurring payments can be processed by our application.
**Implementation Notes**
- ~~The transaction types (`txn_type`) for recurrring payments will be:~~
- `recurring_payment_profile_created`
- `recurring_payment`
- ~~The Fundraising Application needs to be changed to handle those new transaction types.~~
- The notification `recurring_payment_profile_created` should be accepted, but ignored for donation payments.
- ~~Deploy the changed application to test and make a payment. Wait for the IPN to arrive~~
- ~~Look at the paypal.log data for a recurring payment - it should contain a `recurring_payment_id` that will allow us to determine if a recurring payment is for a membership or a donation.~~
- look at the paypal.log for a one-time payment - it should contain a some id (referenced as `<TBD>` in the following steps) that will allow us to match the payment with a donation.
- Check if the IPN has a `custom` field, if yes, you can use the donation ID and security token from the custom field
If the IPN has no custom field, you need to look for a payment with the right external id (joining the membership //and// donation table to find out what the payment is for). Create a new class for this - it should receive the IPN data look at the transaction type to determine the name of the ID field, request membership id and donation id from the database and return a use case with a "lenient" authorizer implementation that always returns `true` for `systemCanModifydonation`.
- Add test cases for the route that check the new payment data
- `recurring_payment` & matching `recurring_payment_id` for donations should be handled
- `recurring_payment` & non-matching `recurring_payment_id` should be dropped (and logged)
- `web_accept` without `custom` field and matching `<TBD>` field should be handled
- `web_accept` without `custom` field and non-matching `<TBD>` field should be dropped (and logged)