How to generate openapi in ktor?

Question

I'm writing some rstAPI with Ktor and want it to be autodocumentated.

I don't need swagger HTML generation and stuff, just raw openapi.yml

Searching for "ktor openapi generation" and etc gives me official docs link (https://ktor.io/docs/server-openapi.htm)

But, if I try to write same code in my project:

fun main() {
  embeddedServer(
    Netty,
    port = Config.load().main.port,
    host = Config.load().main.host,
    module = Application::module
  ).start(wait = true)
}



fun Application.module() {
  routing {

    route("/api") {
      get {
        call.respond("Hello world!")
      }
    }

    openAPI(path = "/api/openapi", swaggerFile = "documentation.yaml", )


  }
}

It just gives me FileNotFoundException

Exception in thread "main" java.io.FileNotFoundException: Swagger file not found: documentation.yaml
        at io.ktor.server.plugins.openapi.OpenAPIKt.readOpenAPIFile(OpenAPI.kt:57)
        at io.ktor.server.plugins.openapi.OpenAPIKt.openAPI(OpenAPI.kt:27)
        at io.ktor.server.plugins.openapi.OpenAPIKt.openAPI$default(OpenAPI.kt:22)
        at _4Tipsy.TinyCloudAPI.AppKt$module$1.invoke(App.kt:39)
        ...

As I got it, io.ktor:ktor-server-openapi wasn't made for openapi generation.

So, please, tell me about any solution.

Answer 1

You can generate the OpenAPI specification for a Ktor server application with the official Ktor plugin built into the IntelliJ IDEA Ultimate. Alternatively, the specification can be generated with a third-party tool Kopendium, which allows documenting the server API through code.

Answer 2

You can use the ktor-swagger-ui library by SMILEY4 to easily integrate Swagger UI into your Ktor application. This library allows you to automatically host a Swagger UI route for your defined API routes, enabling you to view and interact with your API documentation directly in the browser.