http4scors.scala

// using lib org.http4s::http4s-ember-server:0.23.7
// using lib org.http4s::http4s-blaze-server:0.23.7
// using lib org.http4s::http4s-circe:0.23.7
// using lib org.http4s::http4s-dsl:0.23.7
// using scala 2.13.7
// using options -Xsource:3.0 -Wunused:imports -deprecation
import cats.effect.IO
import cats.effect.IOApp
import io.circe.Decoder
import org.http4s.HttpRoutes
import org.http4s.blaze.server.BlazeServerBuilder
import org.http4s.circe.CirceEntityCodec._
import org.http4s.dsl.io._
import org.http4s.server.middleware.CORS
import org.http4s.server.middleware.CORSConfig

object demo extends IOApp.Simple {

  case class Foo(s: String)
  implicit val decoder: Decoder[Foo] = Decoder.forProduct1("s")(Foo.apply)

  def run: IO[Unit] =
    BlazeServerBuilder[IO]
      .withHttpApp {
        CORS(
          HttpRoutes
            .of[IO] { case req @ POST -> Root / "foo" => req.as[Foo] *> Ok() }
            .orNotFound,
          CORSConfig
            .default
            .withAllowCredentials(false)
            .withAnyOrigin(false)
            .withAllowedOrigins(Set("http://localhost:8080"))
            .withAnyMethod(true),
        )
      }
      .resource
      .useForever

}