Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
MQTT Essentials - A Lightweight IoT Protocol

You're reading from   MQTT Essentials - A Lightweight IoT Protocol Send and receive messages with the MQTT protocol for your IoT solutions.

Arrow left icon
Product type Paperback
Published in Apr 2017
Publisher Packt
ISBN-13 9781787287815
Length 280 pages
Edition 1st Edition
Languages
Tools
Arrow right icon
Author (1):
Arrow left icon
Gaston C. Hillar Gaston C. Hillar
Author Profile Icon Gaston C. Hillar
Gaston C. Hillar
Arrow right icon
View More author details
Toc

Table of Contents (8) Chapters Close

Preface 1. Lightweight Messaging with MQTT 3.1.1 and Mosquitto FREE CHAPTER 2. Securing an MQTT Mosquitto Server 3. Controlling a Drone with Python 4. Interacting with Sensors in Java 5. Controlling Home Automation in JavaScript 6. Interacting with Actuators in Swift A. Exersise Answers

Processing commands with Python


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

{"COMMAND": "SET_MAX_ALTITUDE", "FEET": 20}
{"COMMAND": "SET_MIN_ALTITUDE", "FEET": 10}
{"COMMAND": "TAKE_OFF"}
{"COMMAND": "MOVE_UP"}
{"COMMAND": "ROTATE_RIGHT", "DEGREES": 90}
{"COMMAND": "MOVE_RIGHT"}
{"COMMAND": "LAND"}

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...
lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at $19.99/month. Cancel anytime