An introduction to microservices

Let's start by going over the concept of microservices. In the legacy world, applications were delivered in a monolithic architecture. This meant that multiple services were hosted together on a single node. In the microservice architecture, the application is divided into several microservices, each hosted on a separate node, like so:

Figure 6.1 – Monolithic versus microservice

Each microservice is responsible for a single piece of functionality. The microservices are loosely coupled and can be developed and managed separately. They communicate with each other using APIs. Thanks to that, each microservice can even be developed in a different programming language. When you need to upgrade your application, you can upgrade a single service without affecting other components. By splitting the application into microservices, you also have control over how and when you scale your application. You can granularly scale...