Book Image

Akka Cookbook

By : Vivek Mishra, Héctor Veiga Ortiz
Book Image

Akka Cookbook

By: Vivek Mishra, Héctor Veiga Ortiz

Overview of this book

Akka is an open source toolkit that simplifies the construction of distributed and concurrent applications on the JVM. This book will teach you how to develop reactive applications in Scala using the Akka framework. This book will show you how to build concurrent, scalable, and reactive applications in Akka. You will see how to create high performance applications, extend applications, build microservices with Lagom, and more. We will explore Akka's actor model and show you how to incorporate concurrency into your applications. The book puts a special emphasis on performance improvement and how to make an application available for users. We also make a special mention of message routing and construction. By the end of this book, you will be able to create a high-performing Scala application using the Akka framework.
Table of Contents (18 chapters)
Title Page
About the Authors
About the Reviewer
Customer Feedback

Creating a persistence FSM model

FSM stands for finite-state machine. Akka provides the functionality to easily create an FSM within an actor. To learn more about FSM and Akka, take a look at the Finite-state machine recipe in Chapter 10, Understanding Various Akka Patterns. From this point, we will assume you have some basic knowledge of Akka FSM. Akka persistence also you to make your FSM persistent. When our FSM changes from one state to another, the change gets persisted, and therefore it's possible to restart our FSM with the latest state.

In this recipe, we will look at how to integrate persistence in your Akka FSM application using a countdown latch as an example. A countdown latch is a synchronization primitive that allows one or more threads to wait until a certain number of operations are completed on other threads. In this example, we will persist the number of operations to be able to restore in case of failure.

Getting ready

To step through this recipe, we need to import the hello...