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)

The Throttling Pattern

The Throttling Reactive Pattern is a Reactive System's Flow control pattern. It is also known as the Message Throttler.

Our Reactive System has some external dependencies, such as the REST API. We want to make HTTP requests to that external REST API. The REST API has the following restrictions:

  • It accepts only 10 requests per minute from an endpoint
  • If it receives more than 10 requests in 1 minute, it will block the endpoint requests, or if we want to proceed, we need to pay some money

If we have this kind of restriction in our external components or systems, then it's good to use the Throttler.

A Throttler Design Pattern allows us to implement a component that sends requests to external components based on our configurations.

For instance, if we need a time-based Throttler to send requests to the preceding REST API, then we can configure how...