From 429b08a0e1087d963a5770aa273d431a72af093f Mon Sep 17 00:00:00 2001
From: Vladimir Dementyev <palkan@hey.com>
Date: Mon, 26 Feb 2024 17:00:01 -0800
Subject: [PATCH] fix(core): do not send pongs when cable is not connected

Fixes #33
---
 packages/core/CHANGELOG.md                   |  2 ++
 packages/core/action_cable_ext/index.js      |  5 ++++-
 packages/core/action_cable_ext/index.test.ts | 10 ++++++++++
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/packages/core/CHANGELOG.md b/packages/core/CHANGELOG.md
index ecc4f51..49732f9 100644
--- a/packages/core/CHANGELOG.md
+++ b/packages/core/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 ## master
 
+- Do not try to send `pong` if cable is no longer connected. ([@palkan][])
+
 ## 0.7.12 (2024-01-08)
 
 - Omit `undefined` within Channels' params to fix invalid JSON serialization. ([@ardecvz][])
diff --git a/packages/core/action_cable_ext/index.js b/packages/core/action_cable_ext/index.js
index 464a002..9cfac3b 100644
--- a/packages/core/action_cable_ext/index.js
+++ b/packages/core/action_cable_ext/index.js
@@ -152,6 +152,9 @@ export class ActionCableExtendedProtocol extends ActionCableProtocol {
   // Send pongs asynchrounously—no need to block the main thread
   async sendPong() {
     await new Promise(resolve => setTimeout(resolve, 0))
-    this.cable.send({ command: 'pong' })
+    // Only send pong if the connection is still open
+    if (this.cable.state === 'connected') {
+      this.cable.send({ command: 'pong' })
+    }
   }
 }
diff --git a/packages/core/action_cable_ext/index.test.ts b/packages/core/action_cable_ext/index.test.ts
index 63fbdea..401cd46 100644
--- a/packages/core/action_cable_ext/index.test.ts
+++ b/packages/core/action_cable_ext/index.test.ts
@@ -289,6 +289,7 @@ describe('receive', () => {
     })
 
     it('sends pong in response to ping', async () => {
+      cable.connected()
       protocol.receive({ type: 'ping', message: '42' })
       expect(cable.lastPingedAt).toEqual(42)
 
@@ -299,6 +300,15 @@ describe('receive', () => {
         command: 'pong'
       })
     })
+
+    it('does not try to send pong if cable is no longer connected', async () => {
+      protocol.receive({ type: 'ping', message: '42' })
+      expect(cable.lastPingedAt).toEqual(42)
+      cable.disconnected()
+      await new Promise(resolve => setTimeout(resolve, 0))
+
+      expect(cable.mailbox).toHaveLength(0)
+    })
   })
 })