From dea747a9a96dbd04578fd327e027abb81d24dfb5 Mon Sep 17 00:00:00 2001
From: "nicolas.dorier" <nicolas.dorier@gmail.com>
Date: Tue, 5 Oct 2021 13:37:30 +0900
Subject: [PATCH] Keep connection alive on checkout page by sending ping
 messages

---
 BTCPayServer/Controllers/InvoiceController.UI.cs | 4 ++--
 BTCPayServer/Views/Invoice/Checkout.cshtml       | 3 +++
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/BTCPayServer/Controllers/InvoiceController.UI.cs b/BTCPayServer/Controllers/InvoiceController.UI.cs
index ac6b152d5..6f0690c6d 100644
--- a/BTCPayServer/Controllers/InvoiceController.UI.cs
+++ b/BTCPayServer/Controllers/InvoiceController.UI.cs
@@ -654,7 +654,7 @@ namespace BTCPayServer.Controllers
         [Route("invoice/{invoiceId}/status/ws")]
         [Route("invoice/{invoiceId}/{paymentMethodId}/status")]
         [Route("invoice/status/ws")]
-        public async Task<IActionResult> GetStatusWebSocket(string invoiceId)
+        public async Task<IActionResult> GetStatusWebSocket(string invoiceId, CancellationToken cancellationToken)
         {
             if (!HttpContext.WebSockets.IsWebSocketRequest)
                 return NotFound();
@@ -670,7 +670,7 @@ namespace BTCPayServer.Controllers
                 leases.Add(_EventAggregator.Subscribe<Events.InvoiceEvent>(async o => await NotifySocket(webSocket, o.Invoice.Id, invoiceId)));
                 while (true)
                 {
-                    var message = await webSocket.ReceiveAsync(DummyBuffer, default(CancellationToken));
+                    var message = await webSocket.ReceiveAndPingAsync(DummyBuffer, default(CancellationToken));
                     if (message.MessageType == WebSocketMessageType.Close)
                         break;
                 }
diff --git a/BTCPayServer/Views/Invoice/Checkout.cshtml b/BTCPayServer/Views/Invoice/Checkout.cshtml
index 8b21dc9c4..73b73c8e2 100644
--- a/BTCPayServer/Views/Invoice/Checkout.cshtml
+++ b/BTCPayServer/Views/Invoice/Checkout.cshtml
@@ -276,9 +276,12 @@
                     }
                     ws_uri += "//" + loc.host;
                     ws_uri += loc.pathname + "/status/ws?invoiceId=" + this.srvModel.invoiceId;
+
                     try {
                         socket = new WebSocket(ws_uri);
                         socket.onmessage = function (e) {
+                            if (e.data === "ping")
+                                return;
                             self.fetchData();
                         };
                         socket.onerror = function (e) {