gemini-hlsw · hugo-vrijswijk · May 8, 2026 · May 7, 2026 · May 7, 2026 · May 7, 2026
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -29,8 +29,11 @@ jobs:
       matrix:
         os: [ubuntu-22.04]
         scala: [3.8.3]
-        java: [temurin@17]
+        java: [temurin@25, temurin@17]
         project: [rootJS, rootJVM]
+        exclude:
+          - project: rootJS
+            java: temurin@17
     runs-on: ${{ matrix.os }}
     timeout-minutes: 60
     steps:
@@ -42,6 +45,19 @@ jobs:
       - name: Setup sbt
         uses: sbt/setup-sbt@v1
 
+      - name: Setup Java (temurin@25)
+        id: setup-java-temurin-25
+        if: matrix.java == 'temurin@25'
+        uses: actions/setup-java@v5
+        with:
+          distribution: temurin
+          java-version: 25
+          cache: sbt
+
+      - name: sbt update
+        if: matrix.java == 'temurin@25' && steps.setup-java-temurin-25.outputs.cache-hit == 'false'
+        run: sbt +update
+
       - name: Setup Java (temurin@17)
         id: setup-java-temurin-17
         if: matrix.java == 'temurin@17'
@@ -59,11 +75,11 @@ jobs:
         run: sbt githubWorkflowCheck
 
       - name: Check headers and formatting
-        if: matrix.java == 'temurin@17' && matrix.os == 'ubuntu-22.04'
+        if: matrix.java == 'temurin@25' && matrix.os == 'ubuntu-22.04'
         run: sbt 'project ${{ matrix.project }}' '++ ${{ matrix.scala }}' headerCheckAll scalafmtCheckAll 'project /' scalafmtSbtCheck lucumaScalafmtCheck lucumaScalafixCheck
 
       - name: Check scalafix lints
-        if: matrix.java == 'temurin@17' && matrix.os == 'ubuntu-22.04'
+        if: matrix.java == 'temurin@25' && matrix.os == 'ubuntu-22.04'
         run: sbt 'project ${{ matrix.project }}' '++ ${{ matrix.scala }}' 'scalafixAll --check'
 
       - name: scalaJSLink
@@ -74,11 +90,11 @@ jobs:
         run: sbt 'project ${{ matrix.project }}' '++ ${{ matrix.scala }}' test
 
       - name: Check binary compatibility
-        if: matrix.java == 'temurin@17' && matrix.os == 'ubuntu-22.04'
+        if: matrix.java == 'temurin@25' && matrix.os == 'ubuntu-22.04'
         run: sbt 'project ${{ matrix.project }}' '++ ${{ matrix.scala }}' mimaReportBinaryIssues
 
       - name: Generate API documentation
-        if: matrix.java == 'temurin@17' && matrix.os == 'ubuntu-22.04'
+        if: matrix.java == 'temurin@25' && matrix.os == 'ubuntu-22.04'
         run: sbt 'project ${{ matrix.project }}' '++ ${{ matrix.scala }}' doc
 
       - name: Aggregate coverage reports
@@ -94,7 +110,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-22.04]
-        java: [temurin@17]
+        java: [temurin@25]
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout current branch (full)
@@ -105,6 +121,19 @@ jobs:
       - name: Setup sbt
         uses: sbt/setup-sbt@v1
 
+      - name: Setup Java (temurin@25)
+        id: setup-java-temurin-25
+        if: matrix.java == 'temurin@25'
+        uses: actions/setup-java@v5
+        with:
+          distribution: temurin
+          java-version: 25
+          cache: sbt
+
+      - name: sbt update
+        if: matrix.java == 'temurin@25' && steps.setup-java-temurin-25.outputs.cache-hit == 'false'
+        run: sbt +update
+
       - name: Setup Java (temurin@17)
         id: setup-java-temurin-17
         if: matrix.java == 'temurin@17'

diff --git a/.mergify.yml b/.mergify.yml
@@ -13,7 +13,8 @@ pull_request_rules:
     - body~=labels:.*early-semver-patch
     - body~=labels:.*early-semver-minor
     - 'title=flake.lock: Update'
-  - status-success=Test (ubuntu-22.04, 3.8.3, temurin@17, rootJS)
+  - status-success=Test (ubuntu-22.04, 3.8.3, temurin@25, rootJS)
+  - status-success=Test (ubuntu-22.04, 3.8.3, temurin@25, rootJVM)
   - status-success=Test (ubuntu-22.04, 3.8.3, temurin@17, rootJVM)
   actions:
     merge: {}

diff --git a/.scalafix.conf b/.scalafix.conf
@@ -1,3 +1,4 @@
 include ".scalafix-common.conf"
 
 OrganizeImports.removeUnused = false # scala 3
+OrganizeImports.targetDialect = Scala3
diff --git a/build.sbt b/build.sbt
@@ -1,8 +1,8 @@
 lazy val V = _root_.scalafix.sbt.BuildInfo
 
-ThisBuild / tlBaseVersion               := "0.52"
+ThisBuild / tlBaseVersion               := "0.53"
 ThisBuild / tlJdkRelease                := Some(17)
-ThisBuild / githubWorkflowJavaVersions  := Seq("17").map(JavaSpec.temurin(_))
+ThisBuild / githubWorkflowJavaVersions  := Seq("25", "17").map(JavaSpec.temurin(_))
 ThisBuild / scalaVersion                := "3.8.3"
 ThisBuild / crossScalaVersions          := Seq("3.8.3")
 ThisBuild / githubWorkflowScalaVersions := Seq("3.8.3")
@@ -88,7 +88,9 @@ lazy val http4s =
       libraryDependencies ++=
         Settings.Libraries.Http4sCirce.value ++
           Settings.Libraries.Http4sClient.value ++
-          Settings.Libraries.Http4sOtel4sMiddleware.value
+          Settings.Libraries.Http4sOtel4sMiddleware.value ++
+          Settings.Libraries.MUnitCatsEffect.value ++
+          Settings.Libraries.MUnit.value
     )
     .dependsOn(core)
 

diff --git a/http4s/src/main/scala/clue/http4s/Http4sWebSocketBackend.scala b/http4s/src/main/scala/clue/http4s/Http4sWebSocketBackend.scala
@@ -30,43 +30,62 @@ final class Http4sWebSocketBackend[F[_]: Concurrent](client: WSClient[F])
     client
       .connectHighLevel:
         WSRequest(uri).withHeaders(Headers("Sec-WebSocket-Protocol" -> "graphql-transport-ws"))
-      .allocated // TODO replace with allocatedCase
+      .allocated
       .flatMap: (connection, release) =>
-        connection.receiveStream
-          .evalTap:
-            case WSFrame.Text(data, _) => handler.onMessage(connectionId, data)
-            case WSFrame.Binary(_, _)  => Concurrent[F].unit
-          .onFinalizeCase:
-            case ExitCase.Succeeded  =>
-              connection.closeFrame.tryGet.flatMap: closeFrame =>
-                val event = closeFrame
-                  .map(close => CloseParams(close.statusCode, close.reason))
-                  .toRight:
-                    new GraphQLException(
-                      s"Unexpected clean close for WS without close frame. URI: [$uri]"
-                    )
-                handler.onClose(connectionId, event) >> release // TODO
-            case ExitCase.Errored(t) => handler.onClose(connectionId, t.asLeft) >> release // TODO
-            case ExitCase.Canceled   =>
-              handler.onClose(
-                connectionId,
-                new GraphQLException(s"WS listener canceled. URI: [$uri]").asLeft
-              ) >> release // TODO
-          .compile
-          .drain
-          .start
-          .as(new Http4sWSConnection(connection))
+        // Refs to ensure release/close are only executed once
+        val closeFunctionsF = for
+          releaseState <- Ref[F].of(false)
+          closeState   <- Ref[F].of(false)
+          releaseNow    = releaseState
+                            .modify(released => true -> !released)
+                            .flatMap(isNotReleased => release.whenA(isNotReleased))
+          notifyClose   =
+            (event: CloseEvent) =>
+              closeState
+                .modify(closed => true -> !closed)
+                .flatMap(isNotClosed => handler.onClose(connectionId, event).whenA(isNotClosed))
+          canceledClose =
+            notifyClose(new GraphQLException(s"WS listener canceled. URI: [$uri]").asLeft)
+        yield (releaseNow, notifyClose, canceledClose)
+
+        closeFunctionsF.flatMap: (releaseNow, notifyClose, canceledClose) =>
+          connection.receiveStream
+            .evalTap:
+              case WSFrame.Text(data, _) => handler.onMessage(connectionId, data)
+              case WSFrame.Binary(_, _)  => Concurrent[F].unit
+            .onFinalizeCase:
+              case ExitCase.Succeeded  =>
+                connection.closeFrame.tryGet.flatMap: closeFrame =>
+                  val event = closeFrame
+                    .map(close => CloseParams(close.statusCode, close.reason))
+                    .toRight:
+                      new GraphQLException(
+                        s"Unexpected clean close for WS without close frame. URI: [$uri]"
+                      )
+                  notifyClose(event) >> releaseNow
+              case ExitCase.Errored(t) => notifyClose(t.asLeft) >> releaseNow
+              case ExitCase.Canceled   => canceledClose >> releaseNow
+            .compile
+            .drain
+            .start
+            .map(new Http4sWSConnection(connection, _, canceledClose, releaseNow))
+            .guaranteeCase:
+              case Outcome.Succeeded(_) => Concurrent[F].unit
+              case Outcome.Errored(t)   => notifyClose(t.asLeft) >> releaseNow
+              case Outcome.Canceled()   => canceledClose >> releaseNow
 
 object Http4sWebSocketBackend:
   def apply[F[_]: Concurrent](client: WSClient[F]): Http4sWebSocketBackend[F] =
     new Http4sWebSocketBackend(client)
 
 final class Http4sWSConnection[F[_]: Concurrent](
-  private val conn: WSConnectionHighLevel[F]
+  private val conn:       WSConnectionHighLevel[F],
+  private val listener:   Fiber[F, Throwable, Unit],
+  private val onCanceled: F[Unit],
+  private val releaseNow: F[Unit]
 ) extends WebSocketConnection[F]:
   override def send(msg: StreamingMessage.FromClient): F[Unit] =
-    conn.send(WSFrame.Text(msg.asJson.toString))
+    conn.send(WSFrame.Text(msg.asJson.noSpaces))
 
-  // In high-level WS, we cannot specify close code.
   override def closeInternal(closeParameters: Option[CloseParams]): F[Unit] =
-    Concurrent[F].unit // TODO
+    listener.cancel >> onCanceled >> releaseNow
diff --git a/http4s/src/test/scala/clue/http4s/Http4sWebSocketBackendSuite.scala b/http4s/src/test/scala/clue/http4s/Http4sWebSocketBackendSuite.scala
@@ -0,0 +1,56 @@
+// Copyright (c) 2016-2025 Association of Universities for Research in Astronomy, Inc. (AURA)
+// For license information see LICENSE or https://opensource.org/licenses/BSD-3-Clause
+
+package clue.http4s
+
+import cats.Foldable
+import cats.effect.*
+import cats.syntax.all.*
+import clue.ConnectionId
+import clue.websocket.*
+import munit.CatsEffectSuite
+import org.http4s.Uri
+import org.http4s.client.websocket.*
+import org.http4s.syntax.literals.*
+
+class Http4sWebSocketBackendSuite extends CatsEffectSuite:
+
+  test("close releases high-level connection and only notifies onClose once") {
+    for {
+      releases   <- Ref.of[IO, Int](0)
+      closes     <- Ref.of[IO, Int](0)
+      deferred   <- Deferred[IO, WSFrame.Close]
+      wsConn      = new WSConnectionHighLevel[IO]:
+                      override def send(wsf: WSDataFrame): IO[Unit]                                 = IO.unit
+                      override def sendMany[G[_]: Foldable, A <: WSDataFrame](wsfs: G[A]): IO[Unit] =
+                        IO.unit
+                      override def receive: IO[Option[WSDataFrame]]                                 = IO.never
+                      override def subprotocol: Option[String]                                      = none
+                      override def closeFrame: Deferred[IO, WSFrame.Close]                          = deferred
+      wsClient    = new WSClient[IO]:
+                      override def connect(request: WSRequest): Resource[IO, WSConnection[IO]] =
+                        Resource.eval(IO.raiseError(new RuntimeException("unused")))
+                      override def connectHighLevel(
+                        request: WSRequest
+                      ): Resource[IO, WSConnectionHighLevel[IO]] =
+                        Resource.make(IO.pure(wsConn))(_ => releases.update(_ + 1))
+      handler     = new WebSocketHandler[IO]:
+                      override def onMessage(connectionId: ConnectionId, msg: String): IO[Unit]     =
+                        IO.unit
+                      override def onClose(connectionId: ConnectionId, event: CloseEvent): IO[Unit] =
+                        closes.update(_ + 1)
+      connection <- Http4sWebSocketBackend[IO](wsClient).connect(
+                      uri"ws://127.0.0.1/ws",
+                      handler,
+                      ConnectionId.Zero
+                    )
+      _          <- connection.close()
+      _          <- connection.close()
+      _          <- IO.cede
+      releaseN   <- releases.get
+      closeN     <- closes.get
+    } yield {
+      assertEquals(releaseN, 1)
+      assertEquals(closeN, 1)
+    }
+  }
diff --git a/scalajs/src/main/scala/clue/js/FetchJsBackend.scala b/scalajs/src/main/scala/clue/js/FetchJsBackend.scala
@@ -46,7 +46,7 @@ final class FetchJsBackend[F[_]: Async](fetchMethod: FetchMethod)
               baseRequest.uri.toString,
               new RequestInit {
                 method = HttpMethod.POST
-                body = request.asJson.toString
+                body = request.asJson.noSpaces
                 headers = _headers
                 signal = _signal
               }

diff --git a/scalajs/src/main/scala/clue/js/WebSocketJsBackend.scala b/scalajs/src/main/scala/clue/js/WebSocketJsBackend.scala
@@ -101,7 +101,7 @@ object WebSocketJsBackend {
 final class WebSocketJsConnection[F[_]: Sync: Logger](private val ws: WebSocket)
     extends WebSocketConnection[F] {
   override def send(msg: StreamingMessage.FromClient): F[Unit] =
-    Sync[F].delay(ws.send(msg.asJson.toString))
+    Sync[F].delay(ws.send(msg.asJson.noSpaces))
 
   override def closeInternal(closeParameters: Option[CloseParams]): F[Unit] =
     "Disconnecting WebSocket...".traceF >>