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)

Configuring TLS client certificate authentication in Mosquitto

Now, we will configure Mosquitto to use TLS client certificate authentication. This way, any client will require the ca.crt file and a client certificate, such as the recently generated board001.crt file, to establish a communication with the Mosquitto server.

If you are running the Mosquitto server in a Terminal window in macOS or Linux, press Ctrl + C to stop it. In Windows, stop the appropriate service.

Go to the Mosquitto installation directory and open the mosquitto.conf configuration file.

In macOS, Linux, or Windows, add the following line at the end of the configuration file:

require_certificate true

We specified the true value for the require_certificate option to make Mosquitto require a valid client certificate for any client that requests a connection to Mosquitto.

Save the changes to the mosquitto.conf...