fix: return preimages for Phoenixd invoices and settled payments (#4068)

lnbits/core/services/payments.py

@@ -632,7 +632,7 @@ async def check_transaction_status(
         return PaymentPendingStatus()
 
     if payment.status == PaymentState.SUCCESS.value:
-        return PaymentSuccessStatus(fee_msat=payment.fee)
+        return PaymentSuccessStatus(fee_msat=payment.fee, preimage=payment.preimage)
 
     return await check_payment_status(payment)
 
@@ -640,7 +640,7 @@ async def check_transaction_status(
 async def check_payment_status(payment: Payment) -> PaymentStatus:
     if payment.is_internal:
         if payment.success:
-            return PaymentSuccessStatus()
+            return PaymentSuccessStatus(fee_msat=payment.fee, preimage=payment.preimage)
         if payment.failed:
             return PaymentFailedStatus()
         if payment.is_in and payment.fiat_provider:

lnbits/wallets/phoenixd.py

@@ -98,6 +98,24 @@ class PhoenixdWallet(Wallet):
             logger.warning(exc)
             return StatusResponse(f"Unable to connect to {self.endpoint}.", 0)
 
+    async def _incoming_preimage(self, payment_hash: str) -> str | None:
+        """Fetch preimage from Phoenixd incoming payment (createinvoice omits it)."""
+        try:
+            r = await self.client.get(
+                f"/payments/incoming/{payment_hash}",
+                timeout=40,
+            )
+            if r.is_error:
+                return None
+            return r.json().get("preimage") or None
+        except Exception as exc:
+            logger.warning(
+                "Phoenixd: could not fetch preimage for %s: %s",
+                payment_hash,
+                exc,
+            )
+            return None
+
     async def create_invoice(
         self,
         amount: int,
@@ -147,7 +165,10 @@ class PhoenixdWallet(Wallet):
 
             checking_id = data["paymentHash"]
             payment_request = data["serialized"]
-            preimage = data.get("paymentPreimage", None)  # if available
+            # Phoenixd createinvoice often omits paymentPreimage.
+            preimage = data.get("paymentPreimage") or await self._incoming_preimage(
+                checking_id
+            )
             return InvoiceResponse(
                 ok=True,
                 checking_id=checking_id,