Testing WebSockets with the Eclipse Paho client JavaScript utility

We will use the Eclipse Paho client JavaScript utility to generate a simple MQTT over WebSockets client on a web browser. We will make this client subscribe to a topic and print all the messages it receives. Follow the next steps:

1. Open a web browser in the same computer in which you are running the Mosquitto server and navigate to http://www.ecli pse.org/paho/clients/js/utility .

2. Enter localhost in Host.

3.  Enter 9001 in Port.

4. Make sure /ws is specified in Path.

5. Make sure the TLS checkbox is unchecked. The following screenshot shows the web page with the appropriate values for the connection options:

   

6. Click Connect. The web page will display Connected to: localhost:9001/ws as, followed by the Client ID that was automatically generated.

7. Go to the Subscribe panel. Enter home/control/leds/1 in Topic, below Subscribe.

8. Select 2 in the QoS dropdown below Subscribe. The following screenshot shows the Subscribe panel with the appropriate...