The introduction of microservices architecture has completely transformed the way in which enterprise applications are viewed. These applications are no longer large monoliths or big services providing the functionality to solve the problems of a specific domain. Instead, we now have small microservices, each providing a specific set of functionalities.

These small microservices communicate with each other over the network to provide a certain output corresponding to the business needs of the organization.

As we move through this chapter, we will see how the traditional approach of doing Enterprise Application Integration (EAI) is being made obsolete by the move towards the use of microservices that have introduced new integration patterns consisting of small, stateless message brokers instead of a large and complex Enterprise Service Bus.

The communication between the clients has now been replaced by the use of API gateways that provide a federation between the clients and the backend microservices.

As a reader of this chapter, you will get to learn about the following:

• Microservices and the change in the EAI landscape
• The transformation of the Enterprise Service Bus
• Thinking EAI in terms of microservices architecture