Tapir seperate static file endpoint description and server logic

Question

I need to serve a small set of static files using tapir with http4s as the implementation. All endpoint definitions are in their own files and exposed using swagger.

The documentation has lots of good examples on serving static files, but without separating the definitions. There's a small section that indicated it is possible.

We would also like to separate the API definition and implementation of the static files. We got it working, but it feels "off". I believe there should be an easier way. My biggest concern is that i suddenly need to summon/pass a CatsMonadError

This is what we have:

• The endpoint def (later we'll add more details)

val index = staticResourcesGetEndpoint.in("")

• the server logic:

class StaticRoutes[F[_]: Async: Logger]:

  val monad: CatsMonadError[F] = new CatsMonadError[F]

  val indexRoutes =
    Http4sServerInterpreter[F]().toRoutes(
      GenericServiceEndpoints.index.serverLogic(
        Resources.get[F](classOf[toto.ServerApp.type].getClassLoader, "html")(monad)
      )
    )

It is working, but is there an easier, better more idiomatic way?

Answer 1

Copying code from the tapir source code, I think the following should work:

package sttp.tapir.examples.static_content

import sttp.tapir.files._
import sttp.tapir.server.ServerEndpoint
import sttp.tapir.server.netty.NettyFutureServer
import sttp.tapir.{InputStreamRange, PublicEndpoint, emptyInput}

import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.Future

object StaticContentFromFilesNettyServer2 extends App {
  val getEndpoint: PublicEndpoint[StaticInput, StaticErrorOutput, StaticOutput[InputStreamRange], Any] =
    staticResourcesGetEndpoint.prependIn(emptyInput)
  val getServerEndpoint: ServerEndpoint[Any, Future] =
    ServerEndpoint.public[StaticInput, StaticErrorOutput, StaticOutput[InputStreamRange], Any, Future](
      getEndpoint,
      Resources.get(this.getClass.getClassLoader, "html")
    )

  NettyFutureServer()
    .port(8080)
    .addEndpoints(List(getServerEndpoint))
    .start()
    .flatMap(_ => Future.never)
}