Book Image

Scala Programming Projects

By : Mikael Valot, Nicolas Jorand
Book Image

Scala Programming Projects

By: Mikael Valot, Nicolas Jorand

Overview of this book

Scala Programming Projects is a comprehensive project-based introduction for those who are new to Scala. Complete with step-by-step instructions and easy-to-follow tutorials that demonstrate best practices when building applications, this Scala book will have you building real-world projects in no time. Starting with the fundamentals of software development, you’ll begin with simple projects, such as developing a financial independence calculator, and then advance to more complex projects, such as a building a shopping application and a Bitcoin transaction analyzer. You’ll explore a variety of Scala features, including its OOP and FP capabilities, and learn how to write concise, reactive, and concurrent applications in a type-safe manner. You’ll also understand how to use libraries such as Akka and Play. Furthermore, you’ll be able to integrate your Scala apps with Kafka, Spark, and Zeppelin, along with deploying applications on a cloud platform. By the end of the book, you’ll have a firm foundation in Java programming that’ll enable you to solve a variety of real-world problems, and you’ll have built impressive projects to add to your professional portfolio.
Table of Contents (18 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

Implementing the server side


At the server level, we need to open a communication channel between the server and the browser; once the communication is open, we need to implement the message reception and broadcast it to all of the connected browsers using Actors.

Creating the web socket route

To create the route, the conf/routes file needs to be modified by adding the following:

GET /v1/cart/events controllers.WebSockets.cartEventWS 

Notice that the route is defined in the same way as a regular web service call; so, the GET call on /v1/cart/events is routed to the cartEventWS method of thecontrollers.WebSockets instance.

Next, we need to create the WebSockets class in the controllers package of the server module, and add the cartEventsWS method, as follows:

@Singleton
class WebSockets @Inject()(
  implicit actorSystem: ActorSystem,
  materializer: Materializer,
  cc: ControllerComponents) extends AbstractController(cc) {

  def cartEventWS = WebSocket.accept[String, String] { 
    implicit request...