Rapid Web API development with Kotlin and Ktor

Ktor is a lightweight framework for building asynchronous servers and clients in connected systems using the power and ease of development of Kotlin. It enables rapid development of REST/JSON API (micro-)services, and web applications with minimal coding. Ktor has clear, simple and extensible architecture based on asynchronous pipelines and interceptors organized in multiple phases. It has many similarities with Spring WebFlux and NodeJS/Express for example, but is more streamlined, flexible, well designed and easy to maintain.

A Ktor Server Application is a custom program listening to one or more ports using a configured server engine, composed by modules with the application logic, that install features, like routing, sessions, compression, json mapping, templates, etc. to handle HTTP/S 1.x/2.x and WebSocket requests. Ktor supports authentication out of the box as a standard pluggable feature including JWT, JWK, OAuth. It allows development of full-stack web applications as Kotlin Multiplatform Projects compiling to JavaScript for the frontend. Ktor has integration with Swagger and support for different types of production metrics such as Dropwizard Metrics.

The presentation concludes with a live demo showing how to implement a REST service and client from scratch, as well as a sample full-stack Kotlin web application as Multiplatform Project. At the end the developed services are deployed on AWS.