Introducing the microservices architecture
Docker and Docker Hub enable development using the microservices architecture. This architecture emphasizes building and running containers that focus on a single aspect of the overall application. When all the containers are running, you have your complete backend application. The containers can be complex, such as a full-blown database server, or simple, such as a short shell script. Ideally, the containers you implement for your application will be simple, short, and focused. Each microservice you write should be simple to debug since you don't need many lines of code.
Suppose we want to develop a backend application that uses MongoDB and Redis and whose application code is written using Node.js. We have the option to create a Dockerfile and start with the MongoDB image. We would then add Redis by installing it using apt, and then add our program to it as we did with the Debian image in Chapter 2, Using VirtualBox and Docker Containers...
