This tutorial will guide you over three different Docker Compose Apps examples. In other words, containers.git will have three different folders:

shellhttpd-mqtt: Based on the previous shellhttpd. This application counts the number of requests and sends them over MQTT.

flask-mqtt-nginx: A typical python3 Flask application implements a web application and receives the MQTT messages from the shellhttpd-mqtt app. The Nginx reverse proxy forwards all the requests to the Flask application.

mosquitto: To enable the MQTT communication between shellhttpd-mqtt and flask-mqtt, the third container establishes an MQTT broker.

shellhttpd-mqtt and mosquitto are examples of Docker Compose Apps using single Docker Container Image.

The flask-mqtt-nginx is an example of Docker Compose Apps using multiple Docker Container Images. In this case, flask-mqtt and nginx.