Learning the basics of Docker

We learned about Docker concepts in Chapter 1, Journey to the Spring World. Now, it is time to test our knowledge and put it into practice. In the first part of this chapter, we will start MongoDB and Postgres instances to serve as a database for our application. We will configure connection settings in the application.

In the last part of this chapter, we will introduce the Maven plugin which provides an easy way to create Docker images via pom.xml with a couple of configurations on file. Finally, we will run our application in a Docker container.