From 55565f1718f47716f5f7bf24b8410158c29931ef Mon Sep 17 00:00:00 2001
From: Kukks <evilkukka@gmail.com>
Date: Tue, 21 Mar 2023 13:48:25 +0100
Subject: [PATCH 1/2] Do not provide lnurl method if ln node is dead

fixes #3541
---
 .../Payments/LNURLPay/LNURLPayPaymentHandler.cs | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/BTCPayServer/Payments/LNURLPay/LNURLPayPaymentHandler.cs b/BTCPayServer/Payments/LNURLPay/LNURLPayPaymentHandler.cs
index 9af7def36..7ce73aa7d 100644
--- a/BTCPayServer/Payments/LNURLPay/LNURLPayPaymentHandler.cs
+++ b/BTCPayServer/Payments/LNURLPay/LNURLPayPaymentHandler.cs
@@ -1,6 +1,8 @@
 #nullable enable
+using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Threading;
 using System.Threading.Tasks;
 using BTCPayServer.Client.Models;
 using BTCPayServer.Configuration;
@@ -20,16 +22,19 @@ namespace BTCPayServer.Payments.Lightning
         private readonly BTCPayNetworkProvider _networkProvider;
         private readonly DisplayFormatter _displayFormatter;
         private readonly LightningLikePaymentHandler _lightningLikePaymentHandler;
+        private readonly LightningClientFactoryService _lightningClientFactoryService;
 
         public LNURLPayPaymentHandler(
             BTCPayNetworkProvider networkProvider,
             DisplayFormatter displayFormatter,
             IOptions<LightningNetworkOptions> options,
-            LightningLikePaymentHandler lightningLikePaymentHandler)
+            LightningLikePaymentHandler lightningLikePaymentHandler,
+            LightningClientFactoryService lightningClientFactoryService)
         {
             _networkProvider = networkProvider;
             _displayFormatter = displayFormatter;
             _lightningLikePaymentHandler = lightningLikePaymentHandler;
+            _lightningClientFactoryService = lightningClientFactoryService;
             Options = options;
         }
 
@@ -62,6 +67,16 @@ namespace BTCPayServer.Payments.Lightning
                 {
                     throw new PaymentMethodUnavailableException("LNURL requires a lightning node to be configured for the store.");
                 }
+                using var cts = new CancellationTokenSource(5000);
+                try
+                {
+                    var client = lnSupported.CreateLightningClient(network, Options.Value, _lightningClientFactoryService);
+                    await client.GetInfo(cts.Token);
+                }
+                catch (OperationCanceledException) when (cts.IsCancellationRequested)
+                {
+                    throw new PaymentMethodUnavailableException("The lightning node did not reply in a timely manner");
+                }
 
                 return new LNURLPayPaymentMethodDetails()
                 {

From ad5752f09b3bcafee66aac6665ba3dce36532a95 Mon Sep 17 00:00:00 2001
From: Dennis Reimann <mail@dennisreimann.de>
Date: Tue, 21 Mar 2023 14:22:10 +0100
Subject: [PATCH 2/2] Reuse LightningTimeout constant

---
 BTCPayServer/Payments/LNURLPay/LNURLPayPaymentHandler.cs    | 2 +-
 .../Payments/Lightning/LightningLikePaymentHandler.cs       | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/BTCPayServer/Payments/LNURLPay/LNURLPayPaymentHandler.cs b/BTCPayServer/Payments/LNURLPay/LNURLPayPaymentHandler.cs
index 7ce73aa7d..a655d07de 100644
--- a/BTCPayServer/Payments/LNURLPay/LNURLPayPaymentHandler.cs
+++ b/BTCPayServer/Payments/LNURLPay/LNURLPayPaymentHandler.cs
@@ -67,7 +67,7 @@ namespace BTCPayServer.Payments.Lightning
                 {
                     throw new PaymentMethodUnavailableException("LNURL requires a lightning node to be configured for the store.");
                 }
-                using var cts = new CancellationTokenSource(5000);
+                using var cts = new CancellationTokenSource(LightningLikePaymentHandler.LightningTimeout);
                 try
                 {
                     var client = lnSupported.CreateLightningClient(network, Options.Value, _lightningClientFactoryService);
diff --git a/BTCPayServer/Payments/Lightning/LightningLikePaymentHandler.cs b/BTCPayServer/Payments/Lightning/LightningLikePaymentHandler.cs
index a33b8c9f1..544b76313 100644
--- a/BTCPayServer/Payments/Lightning/LightningLikePaymentHandler.cs
+++ b/BTCPayServer/Payments/Lightning/LightningLikePaymentHandler.cs
@@ -21,7 +21,7 @@ namespace BTCPayServer.Payments.Lightning
 {
     public class LightningLikePaymentHandler : PaymentMethodHandlerBase<LightningSupportedPaymentMethod, BTCPayNetwork>
     {
-        public static int LIGHTNING_TIMEOUT = 5000;
+        public static readonly int LightningTimeout = 5000;
         readonly NBXplorerDashboard _Dashboard;
         private readonly LightningClientFactoryService _lightningClientFactory;
         private readonly BTCPayNetworkProvider _networkProvider;
@@ -93,7 +93,7 @@ namespace BTCPayServer.Payments.Lightning
             description = description.Replace("{StoreName}", store.StoreName ?? "", StringComparison.OrdinalIgnoreCase)
                                      .Replace("{ItemDescription}", invoice.Metadata.ItemDesc ?? "", StringComparison.OrdinalIgnoreCase)
                                      .Replace("{OrderId}", invoice.Metadata.OrderId ?? "", StringComparison.OrdinalIgnoreCase);
-            using (var cts = new CancellationTokenSource(LIGHTNING_TIMEOUT))
+            using (var cts = new CancellationTokenSource(LightningTimeout))
             {
                 try
                 {
@@ -129,7 +129,7 @@ namespace BTCPayServer.Payments.Lightning
 
             try
             {
-                using var cts = new CancellationTokenSource(LIGHTNING_TIMEOUT);
+                using var cts = new CancellationTokenSource(LightningTimeout);
                 var client = CreateLightningClient(supportedPaymentMethod, network);
                 LightningNodeInformation info;
                 try