Qlik Sense: How to verify WebSocket Ping-Pong requests with Fiddler Classic

[Damien_Villaret]

This article explains how to verify WebSocket Ping-Pong requests with Fiddler Classic.

Environments:

Qlik Sense Enterprise for Windows June 2018 Patch 1 and later

Steps:

1. Install Fiddler Classic from https://www.telerik.com/download/fiddler with default options

2. Open Fiddler and go to Options > HTTPS, check "Decrypt HTTPS" and accept the warnings

3. Check "Ignore certificate errors" to suppress errors in the browser. Alternatively, acknowledge the warning in your browser when they appear.

Confirm the settings by clicking "OK"

4. Make sure that Fiddler is capturing the traffic

5. Access a Qlik Sense app from your browser

6. Back to Fiddler, search for the WebSocket connection for the app in the list (WS icon on the left and URL pattern is /app/xxxx-xxxx-xxxx-xxxx

7. Double-click on the WebSocket connection, you should get to this screen showing WebSocket traffic

A set of Ping-Pong requests should be seen at the interval set for WebSocketPingInterval (See Enabling TCP Keep Alive Functionality In Qlik Sense )