Building Microservices

Chapter 3. How to Model Services

My opponent’s reasoning reminds me of the heathen, who, being asked on what the world stood, replied, “On a tortoise.” But on what does the tortoise stand? “On another tortoise.”

Joseph Barker (1854)

So you know what microservices are, and hopefully have a sense of their key benefits. You’re probably eager now to go and start making them, right? But where to start? In this chapter, we’ll look at how to think about the boundaries of your microservices that will hopefully maximize the upsides and avoid some of the potential downsides. But first, we need something to work with.

Introducing MusicCorp

Books about ideas work better with examples. Where possible, I’ll be sharing stories from real-world situations, but I’ve found it’s also useful to have a fictional domain with which to work. Throughout the book, we’ll be returning to this domain, seeing how the concept of microservices works within this world.

So let’s turn our attention to the cutting-edge online retailer MusicCorp. MusicCorp was recently a brick-and-mortar retailer, but after the bottom dropped out of the gramophone record business it focused more and more of its efforts online. The company has a website, but feels that now is the time to double-down on the online world. After all, those iPods are just a passing fad (Zunes are way better, obviously) and music fans are quite happy to wait for CDs to arrive at their doorsteps. Quality over convenience, right? And while we’re at it, ...