Merge pull request #8346 from yyforyongyu/remove-error-return

routing+routerrpc: remove redudant error check

lnrpc/routerrpc/router_server.go

@@ -347,30 +347,13 @@ func (s *Server) SendPaymentV2(req *SendPaymentRequest,
 		return err
 	}
 
-	// Send the payment.
+	// Send the payment asynchronously.
-	err = s.cfg.Router.SendPaymentAsync(payment, paySession, shardTracker)
+	s.cfg.Router.SendPaymentAsync(payment, paySession, shardTracker)
-	if err == nil {
-		// If the payment was sent successfully, we can start tracking
-		// the events.
-		return s.trackPayment(
-			sub, payHash, stream, req.NoInflightUpdates,
-		)
-	}
 
-	// Otherwise, transform user errors to grpc code.
+	// Track the payment and return.
-	if errors.Is(err, channeldb.ErrPaymentInFlight) ||
+	return s.trackPayment(
-		errors.Is(err, channeldb.ErrAlreadyPaid) {
+		sub, payHash, stream, req.NoInflightUpdates,
-
+	)
-		log.Debugf("SendPayment async result for payment %x: %v",
-			payment.Identifier(), err)
-
-		return status.Error(codes.AlreadyExists, err.Error())
-	}
-
-	log.Errorf("SendPayment async error for payment %x: %v",
-		payment.Identifier(), err)
-
-	return err
 }
 
 // EstimateRouteFee allows callers to obtain a lower bound w.r.t how much it
@@ -889,10 +872,17 @@ func (s *Server) trackPayment(subscription routing.ControlTowerSubscriber,
 		stream.Context(), subscription, noInflightUpdates, stream.Send,
 	)
 
+	// If the context is canceled, we don't return an error.
 	if errors.Is(err, context.Canceled) {
-		log.Debugf("Payment stream %v canceled", identifier)
+		log.Infof("Payment stream %v canceled", identifier)
+
+		return nil
 	}
 
+	// Otherwise, we will log and return the error as the stream has
+	// received an error from the payment lifecycle.
+	log.Errorf("TrackPayment got error for payment %x: %v", identifier, err)
+
 	return err
 }
 

routing/router.go

@@ -2386,7 +2386,7 @@ func (r *ChannelRouter) SendPayment(payment *LightningPayment) ([32]byte,
 // SendPaymentAsync is the non-blocking version of SendPayment. The payment
 // result needs to be retrieved via the control tower.
 func (r *ChannelRouter) SendPaymentAsync(payment *LightningPayment,
-	ps PaymentSession, st shards.ShardTracker) error {
+	ps PaymentSession, st shards.ShardTracker) {
 
 	// Since this is the first time this payment is being made, we pass nil
 	// for the existing attempt.
@@ -2406,8 +2406,6 @@ func (r *ChannelRouter) SendPaymentAsync(payment *LightningPayment,
 				payment.Identifier(), err)
 		}
 	}()
-
-	return nil
 }
 
 // spewPayment returns a log closures that provides a spewed string