APIC allows you to test Websockets (Native Websocket & Stomp) my connecting to a websocket enabled URL and subscribing to an exchange. Any data you receive will be shown in the Messages section. You can also send data to any exchange as well.
To test websocket requests open an Websocket tab in the Tester module by clicking on the ws button as shown below
Testing Stomp over Websocket
With APIC you can test STOMP enabled websockets. To start
Enter the STOMP endpoint/URL
Select Stomp from the dropdown beside the URL bar
Specify the subscription URL
Specify Stomp Virtual Host name (if any)
Specify Username and Password to connect to the exchange (if required)
Specify additional header you want to send
Click Connect and you are done
Now you can see all incoming messages to the subscribed URL.
To data/messages to ant exchange, click on the Send button in the Messages panel, specify the Destination exchange and message to be sent and click Send.
You can directly connect to any websocket endpoints (ws:// or wss://) by directly specifying the URL in the URL bar and selecting Websocket from the dropdown beside it.