Add Scala.js support to sttp client

Make client tests async so we can run them on JS.
Move client testserver into its own sbt subproject so we can use it from the ScalaTest JS runner.

build.sbt

@@ -2,17 +2,7 @@ import java.util.concurrent.atomic.AtomicInteger
 
 import com.softwaremill.SbtSoftwareMillBrowserTestJS._
 import sbt.Reference.display
-import sbtrelease.ReleaseStateTransformations.{
-  checkSnapshotDependencies,
-  commitReleaseVersion,
-  inquireVersions,
-  publishArtifacts,
-  pushChanges,
-  runClean,
-  runTest,
-  setReleaseVersion,
-  tagRelease
-}
+import sbtrelease.ReleaseStateTransformations.{checkSnapshotDependencies, commitReleaseVersion, inquireVersions, publishArtifacts, pushChanges, runClean, runTest, setReleaseVersion, tagRelease}
 import sbt.internal.ProjectMatrix
 
 val scala2_12 = "2.12.12"
@@ -24,6 +14,9 @@ val documentationScalaVersion = scala2_12 // Documentation depends on finatraSer
 
 scalaVersion := scala2_12
 
+lazy val testServerPort = settingKey[Int]("Port to run the http test server on")
+lazy val startTestServer = taskKey[Unit]("Start a http server used by tests")
+
 val commonSettings = commonSmlBuildSettings ++ ossPublishSettings ++ Seq(
   organization := "com.softwaremill.sttp.tapir",
   libraryDependencies ++= Seq(
@@ -144,6 +137,43 @@ lazy val rootProject = (project in file("."))
   )
   .aggregate(allAggregates: _*)
 
+// start a test server before running tests of a backend; this is required both for JS tests run inside a
+// nodejs/browser environment, as well as for JVM tests where akka-http isn't available (e.g. dotty). To simplify
+// things, we always start the test server.
+val testServerSettings = Seq(
+  test in Test := (test in Test)
+    .dependsOn(startTestServer in testServer2_13)
+    .value,
+  testOnly in Test := (testOnly in Test)
+    .dependsOn(startTestServer in testServer2_13)
+    .evaluated,
+  testOptions in Test += Tests.Setup(() => {
+    val port = (testServerPort in testServer2_13).value
+    PollingUtils.waitUntilServerAvailable(new URL(s"http://localhost:$port"))
+  })
+)
+
+lazy val testServer = (projectMatrix in file("client/testserver"))
+  .settings(commonJvmSettings)
+  .settings(
+    name := "testing-server",
+    skip in publish := true,
+    libraryDependencies ++= loggerDependencies ++ Seq(
+      "org.http4s" %% "http4s-dsl" % Versions.http4s,
+      "org.http4s" %% "http4s-blaze-server" % Versions.http4s,
+      "org.http4s" %% "http4s-circe" % Versions.http4s
+    ),
+    // the test server needs to be started before running any client tests
+    mainClass in reStart := Some("sttp.tapir.client.tests.HttpServer"),
+    reStartArgs in reStart := Seq(s"${(testServerPort in Test).value}"),
+    fullClasspath in reStart := (fullClasspath in Test).value,
+    testServerPort := 51823,
+    startTestServer := reStart.toTask("").value
+  )
+  .jvmPlatform(scalaVersions = List(scala2_13))
+
+lazy val testServer2_13 = testServer.jvm(scala2_13)
+
 // core
 
 lazy val core: ProjectMatrix = (projectMatrix in file("core"))
@@ -190,16 +220,20 @@ lazy val tests: ProjectMatrix = (projectMatrix in file("tests"))
   .settings(
     name := "tapir-tests",
     libraryDependencies ++= Seq(
-      "io.circe" %% "circe-generic" % Versions.circe,
-      "com.beachape" %% "enumeratum-circe" % Versions.enumeratum,
-      "com.softwaremill.common" %% "tagging" % "2.2.1",
+      "io.circe" %%% "circe-generic" % Versions.circe,
+      "com.beachape" %%% "enumeratum-circe" % Versions.enumeratum,
+      "com.softwaremill.common" %%% "tagging" % "2.2.1",
       scalaTest.value,
       "com.softwaremill.macwire" %% "macros" % "2.3.7" % "provided",
-      "org.typelevel" %% "cats-effect" % Versions.catsEffect
+      "org.typelevel" %%% "cats-effect" % Versions.catsEffect
     ),
     libraryDependencies ++= loggerDependencies
   )
   .jvmPlatform(scalaVersions = allScalaVersions)
+  .jsPlatform(
+    scalaVersions = allScalaVersions,
+    settings = commonJsSettings
+  )
   .dependsOn(core, circeJson, enumeratum, cats)
 
 // integrations
@@ -690,21 +724,39 @@ lazy val clientTests: ProjectMatrix = (projectMatrix in file("client/tests"))
     )
   )
   .jvmPlatform(scalaVersions = allScalaVersions)
+  .jsPlatform(
+    scalaVersions = allScalaVersions,
+    settings = commonJsSettings
+  )
   .dependsOn(tests)
 
 lazy val sttpClient: ProjectMatrix = (projectMatrix in file("client/sttp-client"))
-  .settings(commonJvmSettings)
+  .settings(testServerSettings)
   .settings(
     name := "tapir-sttp-client",
     libraryDependencies ++= Seq(
       "com.softwaremill.sttp.client3" %%% "core" % Versions.sttp,
+    )
+  )
+  .jvmPlatform(
+    scalaVersions = allScalaVersions,
+    settings = commonJvmSettings ++ Seq(
+      libraryDependencies ++=  loggerDependencies ++ Seq(
       "com.softwaremill.sttp.client3" %% "async-http-client-backend-fs2" % Versions.sttp % Test,
       "com.softwaremill.sttp.shared" %% "fs2" % Versions.sttpShared % Optional,
       "com.softwaremill.sttp.shared" %% "akka" % Versions.sttpShared % Optional,
       "com.typesafe.akka" %% "akka-stream" % Versions.akkaStreams % Optional
     )
+    )
+  )
+  .jsPlatform(
+    scalaVersions = allScalaVersions,
+    settings = commonJsSettings ++ Seq(
+      libraryDependencies ++= Seq(
+        "io.github.cquiroz" %%% "scala-java-time" % "2.0.0" % Test
+      )
+    )
   )
-  .jvmPlatform(scalaVersions = allScalaVersions)
   .dependsOn(core, clientTests % Test)
 
 lazy val playClient: ProjectMatrix = (projectMatrix in file("client/play-client"))

client/play-client/src/test/scala/sttp/tapir/client/play/PlayClientTests.scala

@@ -8,7 +8,6 @@ import play.api.libs.ws.ahc.StandaloneAhcWSClient
 import sttp.tapir.client.tests.ClientTests
 import sttp.tapir.{DecodeResult, Endpoint}
 
-import scala.concurrent.ExecutionContext.Implicits.global
 import scala.concurrent.{ExecutionContext, Future}
 
 abstract class PlayClientTests[R] extends ClientTests[R] {

client/sttp-client/src/main/scala/sttp/tapir/client/sttp/SttpClientOptions.scala

@@ -1,10 +1,8 @@
 package sttp.tapir.client.sttp
 
-import java.io.File
+import sttp.tapir.{Defaults, TapirFile}
 
-import sttp.tapir.Defaults
-
-case class SttpClientOptions(createFile: () => File)
+case class SttpClientOptions(createFile: () => TapirFile)
 
 object SttpClientOptions {
   implicit val default: SttpClientOptions = SttpClientOptions(Defaults.createTempFile)

client/sttp-client/src/test/scala/sttp/tapir/client/sttp/SttpClientRequestTests.scala

@@ -1,20 +1,19 @@
 package sttp.tapir.client.sttp
 
-import java.io.File
-
 import sttp.tapir._
 import sttp.client3._
 import sttp.tapir.generic.auto._
 import sttp.model.{Header, HeaderNames, MediaType, Part}
 import sttp.tapir.tests.FruitData
 import org.scalatest.funsuite.AnyFunSuite
 import org.scalatest.matchers.should.Matchers
+import sttp.tapir.Defaults.createTempFile
 
 class SttpClientRequestTests extends AnyFunSuite with Matchers {
   test("content-type header shouldn't be duplicated when converting to a part") {
     // given
     val testEndpoint = endpoint.post.in(multipartBody[FruitData])
-    val testFile = File.createTempFile("tapir-", "image")
+    val testFile = createTempFile()
 
     // when
     val sttpClientRequest = testEndpoint

client/sttp-client/src/test/scalajs/sttp/tapir/client/sttp/SttpClientTests.scala

@@ -0,0 +1,37 @@
+package sttp.tapir.client.sttp
+
+import cats.effect.{ContextShift, IO}
+
+import scala.concurrent.Future
+import sttp.tapir.{DecodeResult, Endpoint}
+import sttp.tapir.client.tests.ClientTests
+import sttp.client3._
+
+abstract class SttpClientTests[R >: Any] extends ClientTests[R] {
+  implicit val cs: ContextShift[IO] = IO.contextShift(executionContext)
+  val backend: SttpBackend[Future, R] = FetchBackend()
+  def wsToPipe: WebSocketToPipe[R]
+
+  override def send[I, E, O, FN[_]](e: Endpoint[I, E, O, R], port: Port, args: I, scheme: String = "http"): IO[Either[E, O]] = {
+    implicit val wst: WebSocketToPipe[R] = wsToPipe
+    val response: Future[Either[E, O]] =
+      e.toSttpRequestUnsafe(uri"$scheme://localhost:$port").apply(args).send(backend).map(_.body)
+    IO.fromFuture(IO(response))
+  }
+
+  override def safeSend[I, E, O, FN[_]](
+      e: Endpoint[I, E, O, R],
+      port: Port,
+      args: I
+  ): IO[DecodeResult[Either[E, O]]] = {
+    implicit val wst: WebSocketToPipe[R] = wsToPipe
+    def response: Future[DecodeResult[Either[E, O]]] =
+      e.toSttpRequest(uri"http://localhost:$port").apply(args).send(backend).map(_.body)
+    IO.fromFuture(IO(response))
+  }
+
+  override protected def afterAll(): Unit = {
+    backend.close()
+    super.afterAll()
+  }
+}

client/tests/src/main/scala/sttp/tapir/client/tests/ClientBasicTests.scala

@@ -6,6 +6,7 @@ import java.nio.ByteBuffer
 import sttp.model.{QueryParams, StatusCode}
 import sttp.tapir._
 import sttp.tapir.model.UsernamePassword
+import sttp.tapir.tests.TestUtil.writeToFile
 import sttp.tapir.tests._
 
 trait ClientBasicTests { this: ClientTests[Any] =>
@@ -46,14 +47,15 @@ trait ClientBasicTests { this: ClientTests[Any] =>
         in_query_list_out_header_list,
         port,
         List("plum", "watermelon", "apple")
-      ).unsafeRunSync().right.get should contain theSameElementsAs List("apple", "watermelon", "plum")
+      ).unsafeToFuture().map(_.right.get should contain theSameElementsAs List("apple", "watermelon", "plum"))
     }
     test(in_cookie_cookie_out_header.showDetail) {
       send(
         in_cookie_cookie_out_header,
         port,
         (23, "pomegranate")
-      ).unsafeRunSync().right.get.head.split(" ;") should contain theSameElementsAs "etanargemop=2c ;32=1c".split(" ;")
+      ).unsafeToFuture().map(
+        _.right.get.head.split(" ;") should contain theSameElementsAs "etanargemop=2c ;32=1c".split(" ;"))
     }
     // TODO: test root path
     testClient(in_auth_apikey_header_out_string, "1234", Right("Authorization=None; X-Api-Key=Some(1234); Query=None"))
@@ -88,21 +90,19 @@ trait ClientBasicTests { this: ClientTests[Any] =>
         in_headers_out_headers,
         port,
         List(sttp.model.Header("X-Fruit", "apple"), sttp.model.Header("Y-Fruit", "Orange"))
-      ).unsafeRunSync().right.get should contain allOf (sttp.model.Header("X-Fruit", "elppa"), sttp.model.Header("Y-Fruit", "egnarO"))
+      ).unsafeToFuture().map(_.right.get should contain allOf (sttp.model.Header("X-Fruit", "elppa"), sttp.model.Header("Y-Fruit", "egnarO")))
     }
 
     test(in_json_out_headers.showDetail) {
       send(in_json_out_headers, port, FruitAmount("apple", 10))
-        .unsafeRunSync()
-        .right
-        .get should contain(sttp.model.Header("Content-Type", "application/json".reverse))
+        .unsafeToFuture().map(_.right.get should contain(sttp.model.Header("Content-Type", "application/json".reverse)))
     }
 
     testClient[Unit, Unit, Unit, Nothing](in_unit_out_json_unit, (), Right(()))
 
     test(in_fixed_header_out_string.showDetail) {
       send(in_fixed_header_out_string, port, ())
-        .unsafeRunSync() shouldBe Right("Location: secret")
+        .unsafeToFuture().map(_ shouldBe Right("Location: secret"))
     }
   }
 

client/tests/src/main/scala/sttp/tapir/client/tests/ClientMultipartTests.scala

@@ -8,22 +8,22 @@ trait ClientMultipartTests { this: ClientTests[Any] =>
     testClient(in_simple_multipart_out_string, FruitAmount("melon", 10), Right("melon=10"))
 
     test(in_simple_multipart_out_raw_string.showDetail) {
-      val result = send(in_simple_multipart_out_raw_string, port, FruitAmountWrapper(FruitAmount("apple", 10), "Now!"))
-        .unsafeRunSync()
-        .right
-        .get
-
-      val indexOfJson = result.indexOf("{\"fruit")
-      val beforeJson = result.substring(0, indexOfJson)
-      val afterJson = result.substring(indexOfJson)
-
-      beforeJson should include("""Content-Disposition: form-data; name="fruitAmount"""")
-      beforeJson should include("Content-Type: application/json")
-      beforeJson should not include ("Content-Type: text/plain")
-
-      afterJson should include("""Content-Disposition: form-data; name="notes"""")
-      afterJson should include("Content-Type: text/plain; charset=UTF-8")
-      afterJson should not include ("Content-Type: application/json")
+      send(in_simple_multipart_out_raw_string, port, FruitAmountWrapper(FruitAmount("apple", 10), "Now!"))
+        .unsafeToFuture()
+        .map(_.right.get)
+        .map { result =>
+          val indexOfJson = result.indexOf("{\"fruit")
+          val beforeJson = result.substring(0, indexOfJson)
+          val afterJson = result.substring(indexOfJson)
+
+          beforeJson should include("""Content-Disposition: form-data; name="fruitAmount"""")
+          beforeJson should include("Content-Type: application/json")
+          beforeJson should not include ("Content-Type: text/plain")
+
+          afterJson should include("""Content-Disposition: form-data; name="notes"""")
+          afterJson should include("Content-Type: text/plain; charset=UTF-8")
+          afterJson should not include ("Content-Type: application/json")
+        }
     }
   }