Book Image

Scala Microservices

By : Selvam Palanimalai, Jatin Puri
Book Image

Scala Microservices

By: Selvam Palanimalai, Jatin Puri

Overview of this book

<p>In this book we will learn what it takes to build great applications using Microservices, the pitfalls associated with such a design and the techniques to avoid them. </p><p>We learn to build highly performant applications using Play Framework. You will understand the importance of writing code that is asynchronous and nonblocking and how Play leverages this paradigm for higher throughput. The book introduces Reactive Manifesto and uses Lagom Framework to implement the suggested paradigms. Lagom teaches us to: build applications that are scalable and resilient to failures, and solves problems faced with microservices like service gateway, service discovery, communication and so on. Message Passing is used as a means to achieve resilience and CQRS with Event Sourcing helps us in modelling data for highly interactive applications. </p><p>The book also shares effective development processes for large teams by using good version control workflow, continuous integration and deployment strategies. We introduce Docker containers and Kubernetes orchestrator. Finally, we look at end to end deployment of a set of scala microservices in kubernetes with load balancing, service discovery and rolling deployments. </p><p></p>
Table of Contents (12 chapters)

Play production mode

Play has the following two modes while running an application:

  • Development mode
  • Production mode

Until now, to run our Play application, we have been using the command run on the Play console. When the application server starts, it runs under the development mode. In the development mode, the server would be launched with the auto-reload feature enabled. This means that for each request, Play will automatically detect any change in the source files, recompile them, and restart the server for faster development. This mode is not recommended in production, as it can significantly impact the performance of the application.

To run the application in production mode, we first package our complete application along with its other JAR dependencies in a single ZIP file. To do this, run the dist command on the Play console. The dist task builds a binary version of...