tapir with iron for data validity and better documentation / published by https://github.com/dacr/code-examples-manager #c100bdc5-c628-4aa7-86f3-f838a07a6266/5bbc173d6e90db5befa78aa6ee249eb31270f55f

tapir-with-iron.sc

// summary : tapir with iron for data validity and better documentation
// keywords : scala, zio, tapir, iron, @testable, @exclusive
// publish : gist
// authors : David Crosson
// license : Apache License Version 2.0 (https://www.apache.org/licenses/LICENSE-2.0.txt)
// id : c100bdc5-c628-4aa7-86f3-f838a07a6266
// created-on : 2024-06-06T13:37:39+02:00
// managed-by : https://github.com/dacr/code-examples-manager
// run-with : scala-cli $file
// test-with : curl -L http://127.0.0.1:8080/hello/david

// ---------------------
//> using scala "3.4.2"
//> using dep "com.softwaremill.sttp.tapir::tapir-zio:1.10.9"
//> using dep "com.softwaremill.sttp.tapir::tapir-zio-http-server:1.10.9"
//> using dep "com.softwaremill.sttp.tapir::tapir-iron:1.10.9"
//> using dep "com.softwaremill.sttp.tapir::tapir-json-zio:1.10.9"
//> using dep "com.softwaremill.sttp.tapir::tapir-swagger-ui-bundle:1.10.9"
//> using dep "io.github.iltotore::iron-zio:2.5.0"
//> using dep "io.github.iltotore::iron-zio-json:2.5.0"
// ---------------------

import zio.*
import zio.json.*
import zio.http.Server

import io.github.iltotore.iron.*
import io.github.iltotore.iron.constraint.all.*
import io.github.iltotore.iron.zioJson.given

import sttp.tapir.ztapir.*
import sttp.tapir.server.ziohttp.ZioHttpInterpreter
import sttp.tapir.swagger.bundle.SwaggerInterpreter
import sttp.tapir.json.zio.*
import sttp.tapir.Schema
import sttp.tapir.generic.auto.*
import sttp.tapir.codec.iron.*

import sttp.apispec.openapi.Info

object WebApp extends ZIOAppDefault {

  enum Gender derives JsonCodec {
    case Female, Male
  }

  object Gender {
    given JsonEncoder[Gender] = JsonEncoder[String].contramap(p => p.toString)
    given JsonDecoder[Gender] = JsonDecoder[String].map(p => Gender.valueOf(p))
    given Schema[Gender]      = Schema.derivedEnumeration.defaultStringBased
  }

  case class Salute(
    name: String :| Not[Empty] :| Alphanumeric,
    age: Option[Int :| Positive] /*DescribedAs "Age should be positive"*/,
    gender: Option[Gender],
    nicknames: List[String :| (MinLength[3] & MaxLength[6])] :| Not[Empty]
  )

  object Salute {
    given JsonEncoder[Salute] = DeriveJsonEncoder.gen
    given JsonDecoder[Salute] = DeriveJsonDecoder.gen
  }

  case class Greeting(message: String) derives JsonCodec

  // --------------------------------------------------
  def helloLogic(salute: Salute): UIO[Greeting] = {
    val nicknames:List[String] = salute.nicknames
    for {
      nickName <- Random.shuffle(nicknames).map(_.headOption) // .when(!salute.nicknames.isEmpty)
      name      = nickName.getOrElse(salute.name)
      message   = salute match {
                    case Salute(name, Some(foundAge:Int), _, _) if foundAge < 18  => s"Hi $name"
                    case Salute(name, Some(foundAge), Some(Gender.Female), _) => s"Hello madam $name"
                    case Salute(name, Some(foundAge), Some(Gender.Male), _)   => s"Hello mister $name"
                    case Salute(name, _, _, _)                                => s"Good morning $name"
                  }
    } yield Greeting(message)
  }

  val helloEndPoint =
    endpoint
      .tag("Greetings")
      .name("hello")
      .description("Returns stateful greeting")
      .post
      .in("hello")
      //.in(jsonBody[Salute].example(Salute("Joe", None, None, List("joe"))))
      .in(jsonBody[Salute])
      .out(jsonBody[Greeting])

  val helloRoute = helloEndPoint.zServerLogic[Any](helloLogic)

  // --------------------------------------------------

  val apiDocRoute =
    SwaggerInterpreter()
      .fromServerEndpoints(
        List(helloRoute),
        Info(
          title = "Greeting API",
          version = "1.0",
          description = Some("Everything required to be polite")
        )
      )

  // --------------------------------------------------

  val routes = ZioHttpInterpreter().toHttp(List(helloRoute) ++ apiDocRoute)

  // --------------------------------------------------
  val server = for {
    _ <- ZIO.log("API documentation : http://127.0.0.1:8080/docs")
    _ <- Server.serve(routes)
  } yield ()

  override def run = server.provide(Server.default)
}

WebApp.main(Array.empty)