Fundamentals of Software Architecture

Chapter 17. Microservices Architecture

Microservices is an extremely popular architecture style that has gained significant momentum in recent years. In this chapter, we provide an overview of the important characteristics that set this architecture apart, both topologically and philosophically.

History

Most architecture styles are named after the fact by architects who notice a particular pattern that keeps reappearing—there is no secret group of architects who decide what the next big movement will be. Rather, it turns out that many architects end up making common decisions as the software development ecosystem shifts and changes. The common best ways of dealing with and profiting from those shifts become architecture styles that others emulate.

Microservices differs in this regard—it was named fairly early in its usage and popularized by a famous blog entry by Martin Fowler and James Lewis entitled “Microservices,” published in March 2014. They recognized many common characteristics in this relatively new architectural style and delineated them. Their blog post helped define the architecture for curious architects and helped them understand the underlying philosophy.

Microservices is heavily inspired by the ideas in domain-driven design (DDD), a logical design process for software projects. One concept in particular from DDD, bounded context, decidedly inspired microservices. The concept of bounded context represents a decoupling style. When a developer defines a domain, that ...