Authentication with Ktor
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Launching a Guide to Conquer Authentication with Ktor

ByTomas Zezula

Welcome to the first post on the subject of authentication with Ktor. As developers, we appreciate the importance of security, but integrating it smoothly within our backend services can sometimes seem like a daunting task. However, when working with Kotlin and Ktor, the task becomes much more approachable due to concise syntax and flexibility. This series aims to delve into the diverse authentication mechanisms. We will find our way through Basic Auth, Form Auth, to more complex ones like JWT and OAuth. Whether you’re new to Ktor or looking to broaden your horizons, this series will offer practical, hands-on experiences to help you effectively bring security to your backend applications.

Table of Contents

TLDR;

Go ahead, clone the repository and follow the instructions. The project will grow as this tutorial goes on. For now, it’ll give you everything you need to follow along this journey.

What is Ktor?

Ktor is a Kotlin framework developed by JetBrains. It’s suitable for building server-side applications, particularly RESTful APIs and web applications. The framework supports asynchronous programming and non-blocking I/O out of the box. This can lead to improved scalability and performance.

Ktor is highly modular architecture and easy to learn. Meaning, you are in control of the dependencies you use in your project and you have a great amount of flexibility either when configuring the tool or when building your APIs.

Your Reward for Following This Series

In this tutorial we will build a simple REST API using Ktor’s powerful routing DSL. Throughout this series, we will look into various authenticaton mechanisms to ensure the API can be safely accessed. We will also consider other best security practices, such as implementing CORS, prevention of CSRF attacks, or rate limiting.

At the end of the tutorial, you’ll have a clear understanding how to build resilient APIs with Ktor in a safe manner. You will be able to make informed design choices that are transferrable to many other projects.

Stay tuned for the upcoming articles in this series!

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