How to setup Mosquitto MQTT Broker using docker

These instructions will work on any Debian based OS including Ubuntu, RaspberryPi, WSL2 etc...
(For non-Debian distros, commands for installation need to be tweaked)
By default the config allows only to use local connections for security reasons but since authentication is enabled below, that's not the case.

1. Install docker

Latest instructions are here on docker website.
You can also use this script - install-docker.sh

2. Create Mosquitto password file - pwfile

cd mqtt5broker
touch config/pwfile

3. Create and run docker container for MQTT Broker

# In case you don't have docker-compose you can install it
sudo apt install docker-compose

# Run the docker container for mqtt
sudo docker-compose -p mqtt5broker up -d

Check if the container is up and working (note down container-id)

sudo docker ps

4. Create a user/password in the pwfile

# login interactively into the mqtt container
sudo docker exec -it <container-id> sh

# add user and it will prompt for password
mosquitto_passwd -c /mosquitto/config/pwfile <yourID>

# delete user command format
mosquitto_passwd -D /mosquitto/config/pwfile <user-name-to-delete>

# type 'exit' to exit out of docker container prompt

Then restart the container

sudo docker restart <container-id>

5. Time to test !!!

Install mosquitto client tools for testing

sudo apt install mosquitto-clients

Let us start Subscriber now - topic name => 'hello/topic'

# Without authentication
mosquitto_sub -v -t 'hello/topic'

# With authentication
mosquitto_sub -v -t 'hello/topic' -u <yourID> -P <password>

Let us start Publising to that topic

# Without authentication
mosquitto_pub -t 'hello/topic' -m 'hello MQTT'

# With authentication
mosquitto_pub -t 'hello/topic' -m 'hello MQTT' -u <yourID> -P <password>

You can also install a nice MQTT Web Client

Read more about it here => https://mqttx.app/

sudo docker run -d --name mqttx-web -p 80:80 emqx/mqttx-web

6. Run IoTNode.py to test !!!

We publish simulated temperature, humidity and light sensor data. And we subscribe topics to receive commands to control lamp1, lamp2, lamp3.

# install paho-mqtt to communicate with MQTT broker
pip install paho-mqtt

# run IoTNode.py
python IoTNode.py

Source/Reference for Mosquitto

Github => https://github.com/eclipse/mosquitto