AWS AppSync Subscription Connection Issue – Assistance Needed

[rahul-huma]

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• I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.

JavaScript Framework

React

Amplify APIs

GraphQL API

Amplify Version

v5

Amplify Categories

api

Backend

None

Environment information

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Describe the bug

Hello,

I'm facing an issue with AWS AppSync subscriptions where the connection intermittently breaks, and I've been troubleshooting it for a couple of days now. I am using aws amplify Gen 1(v5). Here’s what happens:

1. Error Message: I frequently encounter the following error:

   A listener indicated an asynchronous response by returning true, but the message channel closed before a response was received.
   

2. Reproducibility: This issue typically occurs in the following scenarios:

   • When the browser window with the AppSync connection remains idle for 2–4 hours.
   • After any network disruption (e.g., intermittent internet connection).

3. Current Setup: I have implemented a retry logic to reconnect when the connection drops. However, I'm struggling to accurately detect whether the subscription is active after reconnection attempts, as the error above can still appear unexpectedly.

I suspect this error is contributing to the connection breaking, and I'd like to confirm if there are any known solutions for handling AWS AppSync subscription stability in long-running or idle scenarios. Additionally, if you have advice on reliably determining the connection status, it would be greatly appreciated.

Thank you in advance for your help!

Expected behavior

I should always retry to connect to the subscription

Reproduction steps

I am just using Gen 1 v5 of this library.

Code Snippet

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Log output

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aws-exports.js

No response

Manual configuration

No response

Additional configuration

No response

Mobile Device

No response

Mobile Operating System

No response

Mobile Browser

No response

Mobile Browser Version

No response

Additional information and screenshots

No response