From 8138c76c1d47fb68a485ca1eb39ca7ab00ea8e59 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Mon, 24 Feb 2025 13:31:21 +0000
Subject: [PATCH] [web] restrict external heartbeat/server ping to websocket
 transport (#23830)

Co-authored-by: Alf Eaton <alf.eaton@overleaf.com>
GitOrigin-RevId: c03a78e2c05cd380b705bd14652060980682cb39
---
 services/real-time/app/js/Router.js                   |  5 ++++-
 .../ide-react/connection/connection-manager.ts        | 11 +++++++----
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/services/real-time/app/js/Router.js b/services/real-time/app/js/Router.js
index a7582be210..269c86698f 100644
--- a/services/real-time/app/js/Router.js
+++ b/services/real-time/app/js/Router.js
@@ -175,7 +175,10 @@ module.exports = Router = {
         return
       }
       const useServerPing =
-        !!client.handshake?.query?.esh && !!client.handshake?.query?.ssp
+        !!client.handshake?.query?.esh &&
+        !!client.handshake?.query?.ssp &&
+        // No server ping with long-polling transports.
+        client.transport === 'websocket'
       const isDebugging = !!client.handshake?.query?.debugging
       const projectId = client.handshake?.query?.projectId
 
diff --git a/services/web/frontend/js/features/ide-react/connection/connection-manager.ts b/services/web/frontend/js/features/ide-react/connection/connection-manager.ts
index 1190ad7f72..e67dcb7e6c 100644
--- a/services/web/frontend/js/features/ide-react/connection/connection-manager.ts
+++ b/services/web/frontend/js/features/ide-react/connection/connection-manager.ts
@@ -248,10 +248,13 @@ export class ConnectionManager extends EventTarget {
       if (this.externalHeartbeatInterval) {
         window.clearInterval(this.externalHeartbeatInterval)
       }
-      this.externalHeartbeatInterval = window.setInterval(
-        () => this.sendExternalHeartbeat(),
-        15_000
-      )
+      if (this.socket.socket.transport?.name === 'websocket') {
+        // Do not enable external heartbeat on polling transports.
+        this.externalHeartbeatInterval = window.setInterval(
+          () => this.sendExternalHeartbeat(),
+          15_000
+        )
+      }
     }
     // Reset on success regardless of transport. We want to upgrade back to websocket on reconnect.
     this.websocketFailureCount = 0