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

Consuming Akka HTTP services using a client-side API

Akka HTTP provides capabilities to consume remote HTTP services. Other frameworks, such as Apache HttpComponents, also provide the same functionality; however, Akka HTTP is asynchronous and streaming-first by default. The Akka HTTP client API uses the same abstractions as the HTTP server API, but it adds the concept of connection pooling. This concept allows developers to reuse connections and improve performance.

It is important to mention that, since Akka HTTP is streaming-first and built on top of Akka streams, there is built-in back pressure. This means that it is required to consume the HTTP entities to signal the stream that you are good to receive new ones. This is required even if you want to discard them. Not doing so might impact your application negatively without apparent reason. The HTTP client API is divided into three levels of abstraction:

  • Connection level: This represents the lowest level. It provides full control of HTTP...