controller_paypal_webhook
Handle PayPal checkout callbacks.
Accept POST events at /paypal/webhook. Decode JSON and verify the signature
through PayPal using the configured webhook ID before processing supported events.
Verified updates enter the shared payment receive logic. Unknown-payment imports
depend on mod_payment configuration. Missing payments return 404 and processing
failures return 500.
Generate the endpoint through its dispatch rule, for example:
{% url paypal_payment_webhook %}
This provider-facing endpoint uses the verification described above rather than an administrator login.