Book Image

MQTT Essentials - A Lightweight IoT Protocol

5 (1)
Book Image

MQTT Essentials - A Lightweight IoT Protocol

5 (1)

Overview of this book

This step-by-step guide will help you gain a deep understanding of the lightweight MQTT protocol. We’ll begin with the specific vocabulary of MQTT and its working modes, followed by installing a Mosquitto MQTT broker. Then, you will use best practices to secure the MQTT Mosquitto broker to ensure that only authorized clients are able to publish and receive messages. Once you have secured the broker with the appropriate configuration, you will develop a solution that controls a drone with Python. Further on, you will use Python on a Raspberry Pi 3 board to process commands and Python on Intel Boards (Joule, Edison and Galileo). You will then connect to the MQTT broker, subscribe to topics, send messages, and receive messages in Python. You will also develop a solution that interacts with sensors in Java by working with MQTT messages. Moving forward, you will work with an asynchronous API with callbacks to make the sensors interact with MQTT messages. Following the same process, you will develop an iOS app with Swift 3, build a website that uses WebSockets to connect to the MQTT broker, and control home automation devices with HTML5, JavaScript code, Node.js and MQTT messages
Table of Contents (16 chapters)
MQTT Essentials - A Lightweight IoT Protocol
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Processing commands with Python

Now, we want to make a drone process the following commands:


Make sure the Mosquitto server or any other MQTT server you might want to use for this example is running.

Launch MQTT.fx and follow all the steps explained in the previous chapter to configure a connection with TLS and TLS authentication. Then, click on the Connect button.

Click Subscribe and enter processed_commands/drone01 in the dropdown on the left-hand side of the Subscribe button. Then, click the Subscribe button. MQTT.fx will display a new panel on the left-hand side with the topic filter to which we have subscribed with a QoS level of 0.

Then, execute the following line to start the example in any computer or device that you want to use as the MQTT client:

python mqtt_essentials_example03_02...