Add module with Http4s Blaze server

build.sbt

@@ -26,7 +26,8 @@ lazy val root =
     `http-scala-fx`,
     documentation,
     `sttp-scala-fx`,
-    `java-net-multipart-body-publisher`
+    `java-net-multipart-body-publisher`,
+    `http4s-scala-fx`
   )
 
 lazy val `scala-fx` = project.settings(scalafxSettings: _*)
@@ -79,6 +80,14 @@ lazy val `sttp-scala-fx` = (project in file("./sttp-scala-fx"))
     `http-scala-fx`,
     `munit-scala-fx` % "test -> compile")
 
+lazy val `http4s-scala-fx` = (project in file("./http4s-scala-fx"))
+  .settings(http4sScalaFXSettings)
+  .dependsOn(
+    `cats-scala-fx`,
+    `scala-fx`,
+    `http-scala-fx` % "test -> test",
+    `munit-scala-fx` % "test -> compile")
+
 lazy val commonSettings = Seq(
   javaOptions ++= javaOptionsSettings,
   autoAPIMappings := true,
@@ -145,6 +154,10 @@ lazy val sttpScalaFXSettings = commonSettings ++ Seq(
   libraryDependencies += hedgehog % Test
 )
 
+lazy val http4sScalaFXSettings = commonSettings ++ Seq(
+  libraryDependencies += http4sBlaze
+)
+
 lazy val javaOptionsSettings = Seq(
   "-XX:+IgnoreUnrecognizedVMOptions",
   "-XX:-DetectLocksInCompiledFrames",

http4s-scala-fx/src/main/scala/http4s/fx/BlazeServerFXBackend.scala

@@ -0,0 +1,51 @@
+package http4s
+package fx
+
+import _root_.fx.handle
+import _root_.fx.instances.StructuredF
+import _root_.fx.instances.FxAsync.asyncInstance
+import _root_.fx.{Control, Errors, Nullable, Resource, Resources, Structured}
+import org.http4s.HttpApp
+import org.http4s.blaze.server.BlazeServerBuilder
+import org.http4s.server.{defaults, Server}
+
+class BlazeServerFXBackend private (
+    app: HttpApp[StructuredF]
+)(
+    using structured: Structured,
+    control: Control[Throwable],
+    config: HttpServerConfig
+) {
+  private var serverFinalizers: Nullable[(Server, StructuredF[Unit])] = Nullable.none
+
+  private val builder: BlazeServerBuilder[StructuredF] =
+    BlazeServerBuilder[StructuredF]
+      .bindHttp(
+        config.port.getOrElse(defaults.HttpPort),
+        config.host.getOrElse(defaults.IPv4Host))
+      .withIdleTimeout(config.idleTimeout.getOrElse(defaults.IdleTimeout))
+      .withSelectorThreadFactory(structured.threadFactory)
+      .withHttpApp(app)
+
+  def start(): BlazeServerFXBackend =
+    serverFinalizers = handle(
+      Nullable(builder.resource.allocated)
+    )((e: Throwable) => e.shift)
+    this
+
+  def close(): Unit =
+    serverFinalizers.map { case (_, finalizers) => finalizers }.getOrElse(())
+
+  def server(): Server =
+    handle(
+      serverFinalizers.map { case (server, _) => server }.value
+    )((e: Throwable) => e.shift)
+}
+
+object BlazeServerFXBackend:
+  def apply(app: HttpApp[StructuredF])(
+      using structured: Structured,
+      control: Control[Throwable],
+      config: HttpServerConfig
+  ): Resource[BlazeServerFXBackend] =
+    Resource(new BlazeServerFXBackend(app).start(), (server, _) => server.close())

http4s-scala-fx/src/main/scala/http4s/fx/HttpServerConfig.scala

@@ -0,0 +1,20 @@
+package http4s
+package fx
+
+import _root_.fx.Nullable
+
+import java.net.InetSocketAddress
+import scala.concurrent.duration.Duration
+
+/**
+ * Defines the server configuration options for an http server. Not open for extension.
+ */
+final class HttpServerConfig(
+    val port: Nullable[Int],
+    val host: Nullable[String],
+    val idleTimeout: Nullable[Duration]
+)
+
+object HttpServerConfig:
+  given HttpServerConfig =
+    HttpServerConfig(Nullable.none, Nullable.none, Nullable.none)

http4s-scala-fx/src/test/scala/http4s/fx/BlazeServerFXBackendSuite.scala

@@ -0,0 +1,37 @@
+package http4s
+package fx
+
+import _root_.fx.{defaultRetryPolicy, parallel, structured, GET, POST, Structured}
+import munit.fx.ScalaFXSuite
+
+import java.net.URI
+import java.net.http.HttpResponse
+
+class BlazeServerFXBackendSuite extends ScalaFXSuite, HttpServerFixtures:
+
+  httpServerHttp4s(pingPongApp).testFX(
+    "GET requests should be returned in non-blocking fibers") { serverResource =>
+    assertEqualsFX(
+      structured {
+        serverResource.use { baseServerAddress =>
+          parallel(
+            () => URI.create(s"$baseServerAddress/ping/1").GET[String]().body,
+            () => URI.create(s"$baseServerAddress/ping/2").GET[String]().body,
+            () => URI.create(s"$baseServerAddress/ping/3").GET[String]().body
+          )
+        }
+      },
+      ("pong", "pong", "pong")
+    )
+  }
+
+  httpServerHttp4s(echoApp).testFX("POST requests should be returned") { serverResource =>
+    val response: HttpResponse[String] = structured {
+      serverResource.use { baseServerAddress =>
+        URI.create(s"$baseServerAddress/echo").POST[String, String]("hello")
+      }
+    }
+
+    assertEqualsFX(response.body, "hello")
+    assertEqualsFX(response.statusCode, 200)
+  }

http4s-scala-fx/src/test/scala/http4s/fx/HttpServerFixtures.scala

@@ -0,0 +1,33 @@
+package http4s
+package fx
+
+import _root_.fx.{handle, structured, toEither, Control, Resource, Structured}
+import _root_.fx.instances.FxAsync.asyncInstance
+import _root_.fx.instances.StructuredF
+import _root_.fx.HttpExecutionException
+import fx.BlazeServerFXBackend
+import munit.FunSuite
+import org.http4s.Method.{GET, POST}
+import org.http4s.{HttpApp, HttpRoutes, Response}
+
+trait HttpServerFixtures:
+  self: FunSuite =>
+
+  val pingPongApp: HttpApp[StructuredF] =
+    HttpApp.apply {
+      case r if r.method == GET && r.uri.path.renderString.contains("ping") =>
+        Response[StructuredF]().withEntity[String]("pong")
+    }
+
+  val echoApp: HttpApp[StructuredF] =
+    HttpApp.apply {
+      case r if r.method == POST && r.uri.path.renderString.contains("echo") =>
+        Response[StructuredF]().withBodyStream(r.body)
+    }
+
+  def httpServerHttp4s(app: HttpApp[StructuredF])
+      : FunFixture[(Structured, Control[Throwable]) ?=> Resource[String]] =
+    FunFixture(
+      setup = _ => BlazeServerFXBackend(app).map(server => s"http:/${server.server().address}"),
+      teardown = _ => ()
+    )

project/project/Dependencies.scala

@@ -32,6 +32,7 @@ object Dependencies {
     val sttp = "3.6.2"
     val httpCore5 = "5.1.4"
     val hedgehog = "0.9.0"
+    val http4sBlaze = "0.23.12"
   }
 
   object Compile {
@@ -47,7 +48,7 @@ object Dependencies {
     val logback = "ch.qos.logback" % "logback-classic" % Versions.logback
     val sttp = "com.softwaremill.sttp.client3" %% "core" % Versions.sttp
     val httpCore5 = "org.apache.httpcomponents.core5" % "httpcore5" % Versions.httpCore5
-
+    val http4sBlaze = "org.http4s" %% "http4s-blaze-server" % Versions.http4sBlaze
   }
 
   object Test {

scala-fx/src/main/scala/fx/Continuation.scala

@@ -4,7 +4,7 @@ import scala.annotation.implicitNotFound
 import scala.util.control.ControlThrowable
 import java.util.UUID
 import scala.util.control.NonFatal
-import java.util.concurrent.ExecutionException
+import java.util.concurrent.{CompletionException, ExecutionException}
 import scala.annotation.tailrec
 
 object Continuation:
@@ -30,7 +30,7 @@ object Continuation:
 
   @tailrec def handleControl(control: Control[_], e: Throwable): Any =
     e match
-      case e: ExecutionException =>
+      case e: (ExecutionException | CompletionException) =>
         handleControl(control, e.getCause)
       case e @ ControlToken(token, shifted, recover) =>
         if (control.token == token)