Book Image

Hands-On MQTT Programming with Python

By : Gaston C. Hillar
Book Image

Hands-On MQTT Programming with Python

By: Gaston C. Hillar

Overview of this book

<p>MQTT is a lightweight messaging protocol for small sensors and mobile devices. This book explores the features of the latest versions of MQTT for IoT and M2M communications, how to use them with Python 3, and allow you to interact with sensors and actuators using Python.</p> <p>The book begins with the specific vocabulary of MQTT and its working modes, followed by installing a Mosquitto MQTT broker. You will use different utilities and diagrams to understand the most important concepts related to MQTT. You will learn to make all the necessary configuration to work with digital certificates for encrypting all data sent between the MQTT clients and the server. You will also work with the different Quality of Service levels and later analyze and compare their overheads.</p> <p>You will write Python 3.x code to control a vehicle with MQTT messages delivered through encrypted connections (TLS 1.2), and learn how leverage your knowledge of the MQTT protocol to build a solution based on requirements. Towards the end, you will write Python code to use the PubNub cloud-based real-time MQTT provider to monitor a surfing competition.</p> <p>In the end, you will have a solution that was built from scratch by analyzing the requirements and then write Python code that will run on water-proof IoT boards connected to multiple sensors in surfboards.</p>
Table of Contents (9 chapters)

Subscribing to topics with a GUI tool

MQTT.fx is a GUI utility implemented with JavaFX that is available for Windows, Linux, and macOS. This tool allows us to connect with an MQTT server, subscribe to topic filters, see received messages, and publish messages to topics. You can download the appropriate version for your operating system from the downloads section of the main web page for this utility: http://www.mqttfx.org.

Now, we will use the MQTT.fx GUI utility to generate another MQTT client that subscribes to the same topic, sensors/octocopter01/altitude, and displays all the messages it receives. We will work with MQTT.fx version 1.6.0. Follow these steps:

  1. Launch MQTT.fx, select local mosquitto in the dropdown located at the upper-left corner, and click on the configuration icon at the right-hand side of this dropdown and at the left-hand side of the Connect button. MQTT...