ZIO learning - playing with sttp async http client and zio json with complex data types / published by https://github.com/dacr/code-examples-manager #fad07854-de71-48ac-a3b8-6789959837c7/4184e1bbb533be9913ce526eedae10b498a8d63c

zio-learning-sttp-client-json-zio-2.sc

// summary : ZIO learning - playing with sttp async http client and zio json with complex data types
// keywords : scala, zio, learning, json, pure-functional, async, sttp, @testable
// publish : gist
// authors : David Crosson
// license : Apache NON-AI License Version 2.0 (https://raw.githubusercontent.com/non-ai-licenses/non-ai-licenses/main/NON-AI-APACHE2)
// id : fad07854-de71-48ac-a3b8-6789959837c7
// created-on : 2022-01-23T11:09:24+01:00
// managed-by : https://github.com/dacr/code-examples-manager
// run-with : scala-cli $file

// ---------------------
//> using scala  "3.3.1"
//> using dep "dev.zio::zio:2.0.13"
//> using dep "fr.janalyse::zio-worksheet:2.0.13.0"
//> using dep "com.softwaremill.sttp.client4::async-http-client-backend-zio:4.0.0-M5"
//> using dep "com.softwaremill.sttp.client4::zio-json:4.0.0-M5"
//> using dep "org.slf4j:slf4j-nop:2.0.7"
// ---------------------

import zio.*, zio.worksheet.*
import zio.json.*

import sttp.client4.*
import sttp.client4.asynchttpclient.zio.*
import sttp.client4.ziojson.*

case class Slide(
  title: String,
  `type`: String,
  items: Option[List[String]] // WARN - Encapsulate into an Option if the field can be omitted
) derives JsonCodec

case class SlideShow(
  author: String,
  date: String,
  slides: List[Slide],
  title: String
) derives JsonCodec

case class Response(
  slideshow: SlideShow
) derives JsonCodec

def run(): Unit = {
  // -------------------------------------------------------------
  // THE APPLICATION LOGIC

  val logic = for {
    sttpBackend <- ZIO.service[SttpBackend[Task, Any]]
    request      = basicRequest.get(uri"https://httpbin.org/json").response(asJson[Response])
    response    <- sttpBackend.send(request)
    clientInfo  <- ZIO.fromEither(response.body)
    _           <- Console.printLine(clientInfo.toString)
  } yield ()

  // -------------------------------------------------------------
  // EXECUTED USING STUBBED STTP ENVIRONNEMENT
  {

    val referenceResponse =
      """{
        |  "slideshow": {
        |    "author": "Yours Truly",
        |    "date": "date of publication",
        |    "slides": [
        |      {
        |        "title": "Wake up to WonderWidgets!",
        |        "type": "all"
        |      },
        |      {
        |        "items": [
        |          "Why <em>WonderWidgets</em> are great",
        |          "Who <em>buys</em> WonderWidgets"
        |        ],
        |        "title": "Overview",
        |        "type": "all"
        |      }
        |    ],
        |    "title": "Sample Slide Show"
        |  }
        |}
        |""".stripMargin

    val httpClientLayer = ZLayer.succeed(
      AsyncHttpClientZioBackend.stub
        .whenRequestMatches(_.uri.toString() == "https://httpbin.org/json")
        .thenRespond(referenceResponse)
    )

    logic.provideLayer(httpClientLayer).unsafeRun
  }

  // -------------------------------------------------------------
  // EXECUTED USING REAL STTP ENVIRONNEMENT
  {
    val httpClientLayer = AsyncHttpClientZioBackend.layer()
    logic.provideLayer(httpClientLayer).unsafeRun
  }

}

run()