SUMMARY

The MQTT module was created as another option of communication for the Mule ESB. MQTT is a protocol typically used in M2M communication, which is tolerant of environments where the client device could get disconnected or experience a high latency situation.

MQTT is similar to many other messaging protocols, such as AMQP and JMS. Communication occurs over a "topic", and has a given Quality of Service (QOS) setting that ranges from "fire and forget" to "guaranteed delivery".

TESTING

Test cases are still being worked on in this module. Please see the "Quick Start" section to get a working environment set up locally.

QUICK START

Requirements: An MQTT Broker (such as Mosquitto), or a freely available public server (list of servers found at http://mqtt.org/wiki/doku.php/public_brokers)

1. Ensure that you have a broker up and running, and are capable of passing messages via a given topic.
2. Ensure you have a running Mule ESB instance. The module has only been tested on Mule ESB v3.2.2
3. Install the MQTT Module into the ESB, or into your Mule application.
4. Create a Mule application. (Either via Mule Studio, or Maven: [http://www.mulesoft.org/documentation/display/MULE3USER/Creating+Project+Archetypes])
5. Install the mqtt namespace into your application.
6. Configure your Mule MQTT module to point to your broker, using the <mqtt:config /> object.
7. Create a new Mule flow. If this flow is subscribing to incoming MQTT messages, use the <mqtt:subscribe /> endpoint. To publish, use <mqtt:publish />.
8. Compile and deploy your application to Mule, ensuring the application starts appropriately.
9. Finally, start sending and receiving messages via MQTT!!

To see a full, in-depth howto, please visit my blog @ http://dnbmiller.wordpress.com.

ADDITIONAL RESOURCES

• Author: Daniel Miller (dmiller@angrygiant.com)
• Twitter: @hockeymann44
• Source Code: http://github.com/dmiller44/mule-module-mqtt
• Documentation: http://dmiller44.github.com/mule-module-mqtt/mule/mqtt.html
• MQTT website: http://mqtt.org
• Eclipse Paho Client (on which the module is based on): https://github.com/eclipse/paho.mqtt.java
• My Blog: http://dnbmiller.wordpress.com