Server

#Introduction

Ktor is built on Coroutine and lets you use only what you need while structuring your application your way. You can also extend Ktor with your own plugins easily.

#Project setup

Generate a “Ktor server application” with Amper.

Two files are created under src: Application.kt and Routing.kt.

Run the project:

Open http://localhost:8080 to confirm it’s running.

You should see “Hello World!”:

#Server

EngineMain starts a server with the selected engine and loads application modules from the external configuration file application.yaml, typically located in the resource directory.

import io.ktor.server.application.*

fun main(args: Array<String>) {
    io.ktor.server.netty.EngineMain.main(args)
}

fun Application.module() {
    configureRouting()
}

In addition to specifying which modules to load, the configuration file can include various server parameters such as the port, host, and SSL settings.

In this link you can find the full list of parameters: Server Configuration

#Amper

To enable Ktor support, you add the following to the module.yaml file:

settings:
  ktor: enabled

Setting ktor: enabled performs the following actions:

• Applies Ktor BOM
• Contributes Ktor-related entries to a built-in library catalog
• Adds the io.ktor.development=true system property when running the app with amper run

You can also customize the version of the Ktor libraries using the full form of the configuration:

settings:
  ktor:
    enabled: true
    version: 3.3.2

#Autoreload

Restarting a server during development can be slow. Ktor supports auto-reload to speed up the feedback loop:

ktor:
    development: true