Book Image

Hands-On Reactive Programming with Clojure - Second Edition

By : Konrad Szydlo, Leonardo Borges
Book Image

Hands-On Reactive Programming with Clojure - Second Edition

By: Konrad Szydlo, Leonardo Borges

Overview of this book

Reactive Programming is central to many concurrent systems, and can help make the process of developing highly concurrent, event-driven, and asynchronous applications simpler and less error-prone. This book will allow you to explore Reactive Programming in Clojure 1.9 and help you get to grips with some of its new features such as transducers, reader conditionals, additional string functions, direct linking, and socket servers. Hands-On Reactive Programming with Clojure starts by introducing you to Functional Reactive Programming (FRP) and its formulations, as well as showing you how it inspired Compositional Event Systems (CES). It then guides you in understanding Reactive Programming as well as learning how to develop your ability to work with time-varying values thanks to examples of reactive applications implemented in different frameworks. You'll also gain insight into some interesting Reactive design patterns such as the simple component, circuit breaker, request-response, and multiple-master replication. Finally, the book introduces microservices-based architecture in Clojure and closes with examples of unit testing frameworks. By the end of the book, you will have gained all the knowledge you need to create applications using different Reactive Programming approaches.
Table of Contents (15 chapters)

Summary

In this chapter, we learned that Clojure futures leave a lot to be desired. More specifically, Clojure futures don't provide a way to express dependencies between results. It doesn't mean, however, that we should dismiss futures altogether.

They are still a useful abstraction and with the right semantics for asynchronous computations and a rich set of combinators, such as the ones provided by imminent, they can be an ally in building reactive applications that are performant and responsive. Sometimes, this is all we need.

For the times where we need to model data that varies over time, we turn to richer frameworks that were inspired by Functional Reactive Programming (FRP) and Compositional Event Systems (CES), such as RxJava, or Communicating Sequential Processes (CSP), such as core.async. As they have a lot more to offer, much of this book has been dedicated...