Book Image

Scala Reactive Programming

By : Rambabu Posa
Book Image

Scala Reactive Programming

By: Rambabu Posa

Overview of this book

Reactive programming is a scalable, fast way to build applications, and one that helps us write code that is concise, clear, and readable. It can be used for many purposes such as GUIs, robotics, music, and others, and is central to many concurrent systems. This book will be your guide to getting started with Reactive programming in Scala. You will begin with the fundamental concepts of Reactive programming and gradually move on to working with asynchronous data streams. You will then start building an application using Akka Actors and extend it using the Play framework. You will also learn about reactive stream specifications, event sourcing techniques, and different methods to integrate Akka Streams into the Play Framework. This book will also take you one step forward by showing you the advantages of the Lagom framework while working with reactive microservices. You will also learn to scale applications using multi-node clusters and test, secure, and deploy your microservices to the cloud. By the end of the book, you will have gained the knowledge to build robust and distributed systems with Scala and Akka.
Table of Contents (16 chapters)

Lagom Hello Reactive System microservices

Even though this basic Lagom HelloWorld System looks very simple, we can learn many Lagom concepts. Let's pick up each service and understand the code.

It mainly has two services (microservices):

  • Hello Lagom service
  • Hello Lagom Stream service

Again, each microservice has two parts: one is for the API and another for the implementation.

The Hello (hello) Microservice has the following two parts:

  • Hello API service (hello-lagom-api)
  • Hello implementation service (hello-lagom-impl)

In the same way, the Hello Stream (hello-lagom-stream) microservice has two parts:

  • Hello Stream API service (hello-lagom-stream-api)
  • Hello Stream implementation service (hello-lagom-stream-impl)

The whole HelloWorld System looks like the following in the IntelliJ IDE:

It's time to understand the code in both the API and the implementation projects...