Book Image

Kotlin Design Patterns and Best Practices - Second Edition

By : Alexey Soshin
Book Image

Kotlin Design Patterns and Best Practices - Second Edition

By: Alexey Soshin

Overview of this book

This book shows you how easy it can be to implement traditional design patterns in the modern multi-paradigm Kotlin programming language, and takes you through the new patterns and paradigms that have emerged. This second edition is updated to cover the changes introduced from Kotlin 1.2 up to 1.5 and focuses more on the idiomatic usage of coroutines, which have become a stable language feature. You'll begin by learning about the practical aspects of smarter coding in Kotlin, as well as understanding basic Kotlin syntax and the impact of design patterns on your code. The book also provides an in-depth explanation of the classical design patterns, such as Creational, Structural, and Behavioral families, before moving on to functional programming. You'll go through reactive and concurrent patterns, and finally, get to grips with coroutines and structured concurrency to write performant, extensible, and maintainable code. By the end of this Kotlin book, you'll have explored the latest trends in architecture and design patterns for microservices. You’ll also understand the tradeoffs when choosing between different architectures and make informed decisions.
Table of Contents (17 chapters)
1
Section 1: Classical Patterns
6
Section 2: Reactive and Concurrent Patterns
11
Section 3: Practical Application of Design Patterns

Chapter 10: Concurrent Microservices with Ktor

In the previous chapter, we explored how we should write idiomatic Kotlin code that will be readable and maintainable, as well as performant.

In this chapter, we'll put the skills we've learned so far to use by building a microservice using the Ktor framework. We also want this microservice to be reactive and to be as close to real life as possible. For that, we'll use the Ktor framework, the benefits of which we'll list in the first section of this chapter.

In this chapter, we will cover the following topics:

  • Getting started with Ktor
  • Routing requests
  • Testing the service
  • Modularizing the application
  • Connecting to a database
  • Creating new entities
  • Making the test consistent
  • Fetching entities
  • Organizing routes in Ktor
  • Achieving concurrency in Ktor

By the end of this chapter, you'll have a microservice written in Kotlin that is well tested and can read data...