Finch with FS2

Main.scala

package finchtest

import cats.effect._
import cats.implicits._
import com.twitter.finagle.Http
import com.twitter.util
import fs2.Stream
import io.finch._
import io.finch.fs2._

class HttpService[F[_]: Effect] extends Endpoint.Module[F] {
  def streaming = post("streaming" :: stringBodyStream[Stream]) { stream: Stream[F, String] =>
    Ok("ok").pure[F]
  }

  def api = streaming.toServiceAs[Text.Plain]
}

object Main extends IOApp {

  def whenTerminated[F[_]](implicit A: Async[F]): F[Unit] = {
    A.async(cb => {
      sys.addShutdownHook(cb(Right(())))
    })
  }

  override def run(args: List[String]): IO[ExitCode] = for {
    http <- IO(Http.serve(s"0.0.0.0:8086", new HttpService[IO].api))
    stop <- IO.race(whenTerminated[IO], IO(util.Await.ready(http)))
    code <- stop match {
      case Left(_) => IO(http.close(util.Duration.Top)).map(_ => 0)
      case Right(_) => IO.pure(1)
    }
  } yield ExitCode(code)

}

curl -D - -X POST -H "Transfer-Encoding: chunked" -H "Content-Type: text/plain" --data-binary "abcdef" 
http://localhost:8086/streaming

HTTP/1.1 404 Not Found
Date: Wed, 13 Feb 2019 13:10:57 GMT
Server: Finch
Content-Length: 0