Make BTCPay webhook configurable.

refs #122

backend/mempool-config.sample.json

@@ -24,5 +24,6 @@
   "SSL_CERT_FILE_PATH": "/etc/letsencrypt/live/mysite/fullchain.pem",
   "SSL_KEY_FILE_PATH": "/etc/letsencrypt/live/mysite/privkey.pem",
   "BTCPAY_URL": "",
+  "BTCPAY_WEBHOOK_URL": "",
   "BTCPAY_AUTH": ""
 }

backend/src/api/donations.ts

@@ -24,7 +24,7 @@ class Donations {
       'orderId': orderId,
       'currency': 'BTC',
       'itemDesc': 'Sponsor mempool.space',
-      'notificationUrl': 'https://mempool.space/api/v1/donations-webhook',
+      'notificationUrl': config.BTCPAY_WEBHOOK_URL,
       'redirectURL': 'https://mempool.space/about'
     };
     return new Promise((resolve, reject) => {