From 12d5c819fb9b0a104c3732ec1e8ee46241ccdbac Mon Sep 17 00:00:00 2001
From: PJ Fanning <pjfanning@users.noreply.github.com>
Date: Fri, 3 Oct 2025 06:41:06 +0100
Subject: [PATCH 1/5] add pekko.http.server.enable-http2 config

---
 http-core/src/main/resources/reference.conf       | 10 +++++++++-
 .../http/impl/settings/ServerSettingsImpl.scala   | 12 ++++++++----
 .../javadsl/settings/PreviewServerSettings.scala  |  4 ++++
 .../http/javadsl/settings/ServerSettings.scala    |  8 ++++++++
 .../org/apache/pekko/http/scaladsl/Http.scala     |  6 +++---
 .../scaladsl/settings/PreviewServerSettings.scala |  3 +++
 .../http/scaladsl/settings/ServerSettings.scala   | 15 +++++++++++++++
 .../pekko/http/scaladsl/ClientServerSpec.scala    |  2 +-
 .../pekko/http/javadsl/Http2JavaServerTest.java   |  2 +-
 .../impl/engine/http2/H2SpecIntegrationSpec.scala |  2 +-
 .../http/impl/engine/http2/H2cUpgradeSpec.scala   |  2 +-
 .../impl/engine/http2/Http2ClientServerSpec.scala |  2 +-
 .../engine/http2/Http2PersistentClientSpec.scala  |  2 +-
 .../http/impl/engine/http2/TelemetrySpiSpec.scala |  2 +-
 .../engine/http2/WithPriorKnowledgeSpec.scala     |  2 +-
 .../pekko/http/scaladsl/Http2ServerTest.scala     |  2 +-
 16 files changed, 59 insertions(+), 17 deletions(-)

diff --git a/http-core/src/main/resources/reference.conf b/http-core/src/main/resources/reference.conf
index fae5ac0b1..12c7c3a18 100644
--- a/http-core/src/main/resources/reference.conf
+++ b/http-core/src/main/resources/reference.conf
@@ -20,6 +20,12 @@ pekko.http {
     # the request, no `Server` header will be rendered at all.
     server-header = pekko-http/${pekko.http.version}
 
+    # If this setting is enabled `Http().newServerAt(...).bind` and `bindSync`
+    # will be enabled to use HTTP/2.
+    #
+    # `Http().newServerAt(...).bindFlow` and `connectionSource()` are not supported.
+    enable-http2 = off
+
     # "PREVIEW" features that are not yet fully production ready.
     # These flags can change or be removed between patch releases.
     preview {
@@ -27,7 +33,9 @@ pekko.http {
       # will be enabled to use HTTP/2.
       #
       # `Http().newServerAt(...).bindFlow` and `connectionSource()` are not supported.
-      enable-http2 = off
+      #
+      # Note that this setting is ignored if `pekko.http.server.enable-http2` is set to `on`.
+      enable-http2 = ${pekko.http.server.enable-http2}
     }
 
     # The time after which an idle connection will be automatically closed.
diff --git a/http-core/src/main/scala/org/apache/pekko/http/impl/settings/ServerSettingsImpl.scala b/http-core/src/main/scala/org/apache/pekko/http/impl/settings/ServerSettingsImpl.scala
index 273645f53..91782018d 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/impl/settings/ServerSettingsImpl.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/impl/settings/ServerSettingsImpl.scala
@@ -14,6 +14,7 @@
 package org.apache.pekko.http.impl.settings
 
 import scala.language.implicitConversions
+import scala.annotation.nowarn
 import scala.collection.immutable
 import scala.concurrent.duration._
 import scala.util.Try
@@ -36,7 +37,7 @@ import pekko.io.Inet.SocketOption
 @InternalApi
 private[pekko] final case class ServerSettingsImpl(
     serverHeader: Option[Server],
-    previewServerSettings: PreviewServerSettings,
+    @nowarn("msg=deprecated") previewServerSettings: PreviewServerSettings,
     timeouts: ServerSettings.Timeouts,
     maxConnections: Int,
     pipeliningLimit: Int,
@@ -56,7 +57,8 @@ private[pekko] final case class ServerSettingsImpl(
     defaultHttpsPort: Int,
     terminationDeadlineExceededResponse: HttpResponse,
     parsingErrorHandler: String,
-    streamCancellationDelay: FiniteDuration) extends ServerSettings {
+    streamCancellationDelay: FiniteDuration,
+    enableHttp2: Boolean) extends ServerSettings {
 
   require(0 < maxConnections, "max-connections must be > 0")
   require(0 < pipeliningLimit && pipeliningLimit <= 1024, "pipelining-limit must be > 0 and <= 1024")
@@ -90,9 +92,10 @@ private[http] object ServerSettingsImpl extends SettingsCompanionImpl[ServerSett
 
   def fromSubConfig(root: Config, c: Config) = {
     val parserSettings = ParserSettingsImpl.fromSubConfig(root, c.getConfig("parsing"))
+    val previewSettings = PreviewServerSettingsImpl.fromSubConfig(root, c.getConfig("preview"))
     new ServerSettingsImpl(
       c.getString("server-header").toOption.map(Server(_)),
-      PreviewServerSettingsImpl.fromSubConfig(root, c.getConfig("preview")),
+      previewSettings,
       Timeouts(
         c.getPotentiallyInfiniteDuration("idle-timeout"),
         if (c.getString("request-timeout") == "off") Duration.Zero
@@ -123,7 +126,8 @@ private[http] object ServerSettingsImpl extends SettingsCompanionImpl[ServerSett
       c.getInt("default-https-port"),
       terminationDeadlineExceededResponseFrom(c),
       c.getString("parsing.error-handler"),
-      c.getFiniteDuration("stream-cancellation-delay"))
+      c.getFiniteDuration("stream-cancellation-delay"),
+      c.getBoolean("enable-http2") || previewSettings.enableHttp2)
   }
 
   private def terminationDeadlineExceededResponseFrom(c: Config): HttpResponse = {
diff --git a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/PreviewServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/PreviewServerSettings.scala
index b69e528f9..44de8d4c3 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/PreviewServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/PreviewServerSettings.scala
@@ -25,8 +25,12 @@ import com.typesafe.config.Config
  * Options that are in "preview" or "early access" mode.
  * These options may change and/or be removed within patch releases
  * without early notice (e.g. by moving them into a stable supported place).
+ *
+ * @deprecated PreviewServerSettings is deprecated, use pekko.http.javadsl.settings.ServerSettings instead (since 2.0.0)
  */
 @ApiMayChange @DoNotInherit
+@Deprecated
+@deprecated("PreviewServerSettings is deprecated, use pekko.http.javadsl.settings.ServerSettings instead", "2.0.0")
 abstract class PreviewServerSettings private[pekko] () { self: PreviewServerSettingsImpl =>
 
   /**
diff --git a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
index 15ca39707..013507adf 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
@@ -34,6 +34,7 @@ import scala.concurrent.duration.{ Duration, FiniteDuration }
  */
 @DoNotInherit abstract class ServerSettings { self: ServerSettingsImpl =>
   def getServerHeader: Optional[Server]
+  @deprecated("the preview server settings are now integrated into the main server settings", "2.0.0")
   def getPreviewServerSettings: PreviewServerSettings
   def getTimeouts: ServerSettings.Timeouts
   def getMaxConnections: Int
@@ -55,11 +56,17 @@ import scala.concurrent.duration.{ Duration, FiniteDuration }
   def getTerminationDeadlineExceededResponse: pekko.http.javadsl.model.HttpResponse
   def getParsingErrorHandler: String
   def getStreamCancellationDelay: FiniteDuration
+  /**
+   * Configures the Http extension to bind using HTTP/2 if given an
+   * [[pekko.http.scaladsl.HttpsConnectionContext]]. Otherwise binds as plain HTTP.
+   */
+  def enableHttp2: Boolean
 
   // ---
 
   def withServerHeader(newValue: Optional[Server]): ServerSettings =
     self.copy(serverHeader = newValue.toScala.map(_.asScala))
+  @deprecated("the preview server settings are now integrated into the main server settings", "2.0.0")
   def withPreviewServerSettings(newValue: PreviewServerSettings): ServerSettings =
     self.copy(previewServerSettings = newValue.asScala)
   def withTimeouts(newValue: ServerSettings.Timeouts): ServerSettings = self.copy(timeouts = newValue.asScala)
@@ -87,6 +94,7 @@ import scala.concurrent.duration.{ Duration, FiniteDuration }
   def withParsingErrorHandler(newValue: String): ServerSettings = self.copy(parsingErrorHandler = parsingErrorHandler)
   def withStreamCancellationDelay(newValue: FiniteDuration): ServerSettings =
     self.copy(streamCancellationDelay = newValue)
+  def withEnableHttp2(newValue: Boolean): ServerSettings = self.copy(enableHttp2 = newValue)
 }
 
 object ServerSettings extends SettingsCompanion[ServerSettings] {
diff --git a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/Http.scala b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/Http.scala
index 17a5044a1..6a7f2692d 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/Http.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/Http.scala
@@ -180,7 +180,7 @@ class HttpExt @InternalStableApi /* constructor signature is hardcoded in Teleme
       connectionContext: ConnectionContext,
       settings: ServerSettings,
       log: LoggingAdapter): Source[Http.IncomingConnection, Future[ServerBinding]] = {
-    if (settings.previewServerSettings.enableHttp2)
+    if (settings.enableHttp2)
       log.warning(
         s"Binding with a connection source not supported with HTTP/2. Falling back to HTTP/1.1 for port [$port]")
 
@@ -221,7 +221,7 @@ class HttpExt @InternalStableApi /* constructor signature is hardcoded in Teleme
       connectionContext: ConnectionContext,
       settings: ServerSettings,
       log: LoggingAdapter)(implicit fm: Materializer): Future[ServerBinding] = {
-    if (settings.previewServerSettings.enableHttp2)
+    if (settings.enableHttp2)
       log.warning(
         s"Binding with a connection source not supported with HTTP/2. Falling back to HTTP/1.1 for port [$port].")
 
@@ -282,7 +282,7 @@ class HttpExt @InternalStableApi /* constructor signature is hardcoded in Teleme
       settings: ServerSettings,
       parallelism: Int,
       log: LoggingAdapter)(implicit fm: Materializer): Future[ServerBinding] = {
-    if (settings.previewServerSettings.enableHttp2) {
+    if (settings.enableHttp2) {
       log.debug("Binding server using HTTP/2")
 
       val definitiveSettings =
diff --git a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala
index acba1b782..5bcac07b7 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala
@@ -24,8 +24,11 @@ import com.typesafe.config.Config
  * Options that are in "preview" or "early access" mode.
  * These options may change and/or be removed within patch releases
  * without early notice (e.g. by moving them into a stable supported place).
+ * 
+ * @deprecated PreviewServerSettings is deprecated, use pekko.http.scaladsl.settings.ServerSettings instead (since 2.0.0)
  */
 @ApiMayChange @DoNotInherit
+@deprecated("PreviewServerSettings is deprecated, use pekko.http.scaladsl.settings.ServerSettings instead", "2.0.0")
 abstract class PreviewServerSettings private[pekko] ()
     extends org.apache.pekko.http.javadsl.settings.PreviewServerSettings {
   self: PreviewServerSettingsImpl =>
diff --git a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
index a655e8448..4b788b3fa 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
@@ -60,10 +60,19 @@ abstract class ServerSettings private[pekko] () extends pekko.http.javadsl.setti
   def terminationDeadlineExceededResponse: HttpResponse
   def parsingErrorHandler: String
   def streamCancellationDelay: FiniteDuration
+  /**
+    * @since 2.0.0
+    */
+  def enableHttp2: Boolean
 
   /* Java APIs */
 
   override def getBacklog = this.backlog
+  /**
+    * @deprecated the preview server settings are now integrated into the main server settings (since 2.0.0)
+    */
+  @Deprecated
+  @deprecated("the preview server settings are now integrated into the main server settings", "2.0.0")
   override def getPreviewServerSettings: pekko.http.javadsl.settings.PreviewServerSettings = this.previewServerSettings
   override def getDefaultHostHeader = this.defaultHostHeader.asJava
   override def getPipeliningLimit = this.pipeliningLimit
@@ -87,6 +96,11 @@ abstract class ServerSettings private[pekko] () extends pekko.http.javadsl.setti
   // ---
 
   // override for more specific return type
+  /**
+   * @deprecated the preview server settings are now integrated into the main server settings (since 2.0.0)
+   */
+  @Deprecated
+  @deprecated("the preview server settings are now integrated into the main server settings", "2.0.0")
   def withPreviewServerSettings(newValue: PreviewServerSettings): ServerSettings =
     self.copy(previewServerSettings = newValue)
   override def withMaxConnections(newValue: Int): ServerSettings = self.copy(maxConnections = newValue)
@@ -110,6 +124,7 @@ abstract class ServerSettings private[pekko] () extends pekko.http.javadsl.setti
   override def withParsingErrorHandler(newValue: String): ServerSettings = self.copy(parsingErrorHandler = newValue)
   override def withStreamCancellationDelay(newValue: FiniteDuration): ServerSettings =
     self.copy(streamCancellationDelay = newValue)
+  override def withEnableHttp2(newValue: Boolean): ServerSettings = self.copy(enableHttp2 = newValue)
 
   // overloads for Scala idiomatic use
   def withTimeouts(newValue: ServerSettings.Timeouts): ServerSettings = self.copy(timeouts = newValue)
diff --git a/http-core/src/test/scala/org/apache/pekko/http/scaladsl/ClientServerSpec.scala b/http-core/src/test/scala/org/apache/pekko/http/scaladsl/ClientServerSpec.scala
index 9f8649d46..e53091199 100644
--- a/http-core/src/test/scala/org/apache/pekko/http/scaladsl/ClientServerSpec.scala
+++ b/http-core/src/test/scala/org/apache/pekko/http/scaladsl/ClientServerSpec.scala
@@ -58,7 +58,7 @@ class ClientServerHttp2EnabledSpec extends ClientServerSpecBase(http2 = true)
 
 abstract class ClientServerSpecBase(http2: Boolean) extends PekkoSpecWithMaterializer(
       s"""
-     pekko.http.server.preview.enable-http2 = $http2
+     pekko.http.server.enable-http2 = $http2
      pekko.http.server.request-timeout = infinite
      pekko.http.server.log-unencrypted-network-bytes = 200
      pekko.http.client.log-unencrypted-network-bytes = 200
diff --git a/http2-tests/src/test/java/org/apache/pekko/http/javadsl/Http2JavaServerTest.java b/http2-tests/src/test/java/org/apache/pekko/http/javadsl/Http2JavaServerTest.java
index 86b822477..8ad281779 100644
--- a/http2-tests/src/test/java/org/apache/pekko/http/javadsl/Http2JavaServerTest.java
+++ b/http2-tests/src/test/java/org/apache/pekko/http/javadsl/Http2JavaServerTest.java
@@ -35,7 +35,7 @@ public static void main(String[] args) {
                 + "pekko.actor.serialize-messages = off\n"
                 + "#pekko.actor.default-dispatcher.throughput = 1000\n"
                 + "pekko.actor.default-dispatcher.fork-join-executor.parallelism-max=8\n"
-                + "pekko.http.server.preview.enable-http2 = on\n");
+                + "pekko.http.server.enable-http2 = on\n");
     ActorSystem system = ActorSystem.create("ServerTest", testConf);
 
     Function<HttpRequest, CompletionStage<HttpResponse>> handler =
diff --git a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/H2SpecIntegrationSpec.scala b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/H2SpecIntegrationSpec.scala
index 63bfb35ef..9907cbf60 100644
--- a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/H2SpecIntegrationSpec.scala
+++ b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/H2SpecIntegrationSpec.scala
@@ -35,7 +35,7 @@ class H2SpecIntegrationSpec extends PekkoFreeSpec(
        loglevel = DEBUG
        loggers = ["org.apache.pekko.http.impl.util.SilenceAllTestEventListener"]
        http.server.log-unencrypted-network-bytes = 100
-       http.server.preview.enable-http2 = on
+       http.server.enable-http2 = on
        http.server.http2.log-frames = on
 
        actor.serialize-creators = off
diff --git a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/H2cUpgradeSpec.scala b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/H2cUpgradeSpec.scala
index 34c0a7413..555e627ec 100644
--- a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/H2cUpgradeSpec.scala
+++ b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/H2cUpgradeSpec.scala
@@ -27,7 +27,7 @@ import pekko.stream.scaladsl.{ Source, Tcp }
 import pekko.util.ByteString
 
 class H2cUpgradeSpec extends PekkoSpecWithMaterializer("""
-    pekko.http.server.preview.enable-http2 = on
+    pekko.http.server.enable-http2 = on
     pekko.http.server.http2.log-frames = on
   """) {
 
diff --git a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/Http2ClientServerSpec.scala b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/Http2ClientServerSpec.scala
index b46ab3c00..75c8d9f5f 100644
--- a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/Http2ClientServerSpec.scala
+++ b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/Http2ClientServerSpec.scala
@@ -52,7 +52,7 @@ import org.scalatest.concurrent.ScalaFutures
 class Http2ClientServerSpec extends PekkoSpecWithMaterializer(
       """pekko.http.server.http2.log-frames = on
      pekko.http.server.log-unencrypted-network-bytes = 100
-     pekko.http.server.preview.enable-http2 = on
+     pekko.http.server.enable-http2 = on
      pekko.http.client.http2.log-frames = on
      pekko.http.client.log-unencrypted-network-bytes = 100
      pekko.actor.serialize-messages = false
diff --git a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/Http2PersistentClientSpec.scala b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/Http2PersistentClientSpec.scala
index 9c5d60b4d..b9e25cfb6 100644
--- a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/Http2PersistentClientSpec.scala
+++ b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/Http2PersistentClientSpec.scala
@@ -62,7 +62,7 @@ abstract class Http2PersistentClientSpec(tls: Boolean) extends PekkoSpecWithMate
       // FIXME: would rather use remote-address-attribute, but that doesn't work with HTTP/2
       // see https://github.com/akka/akka-http/issues/3707
       """pekko.http.server.remote-address-attribute = on
-     pekko.http.server.preview.enable-http2 = on
+     pekko.http.server.enable-http2 = on
      pekko.http.client.http2.log-frames = on
      pekko.http.client.http2.max-persistent-attempts = 5
      pekko.http.client.log-unencrypted-network-bytes = 100
diff --git a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/TelemetrySpiSpec.scala b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/TelemetrySpiSpec.scala
index 0e3ffe4d2..5a0d07cf1 100644
--- a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/TelemetrySpiSpec.scala
+++ b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/TelemetrySpiSpec.scala
@@ -68,7 +68,7 @@ class TelemetrySpiCypherSpec extends TelemetrySpiSpec(true)
 
 abstract class TelemetrySpiSpec(useTls: Boolean) extends PekkoSpecWithMaterializer(
       """
-     pekko.http.server.preview.enable-http2 = on
+     pekko.http.server.enable-http2 = on
      pekko.actor.serialize-messages = false
      pekko.http.http2-telemetry-class = "org.apache.pekko.http.impl.engine.http2.TestTelemetryImpl"
   """) with ScalaFutures with BeforeAndAfterAll {
diff --git a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/WithPriorKnowledgeSpec.scala b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/WithPriorKnowledgeSpec.scala
index 258493cbf..931ba08a4 100644
--- a/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/WithPriorKnowledgeSpec.scala
+++ b/http2-tests/src/test/scala/org/apache/pekko/http/impl/engine/http2/WithPriorKnowledgeSpec.scala
@@ -27,7 +27,7 @@ import pekko.stream.scaladsl.Sink
 import pekko.util.ByteString
 
 class WithPriorKnowledgeSpec extends PekkoSpecWithMaterializer("""
-    pekko.http.server.preview.enable-http2 = on
+    pekko.http.server.enable-http2 = on
     pekko.http.server.http2.log-frames = on
   """) {
 
diff --git a/http2-tests/src/test/scala/org/apache/pekko/http/scaladsl/Http2ServerTest.scala b/http2-tests/src/test/scala/org/apache/pekko/http/scaladsl/Http2ServerTest.scala
index f82f180ae..c6d049e48 100644
--- a/http2-tests/src/test/scala/org/apache/pekko/http/scaladsl/Http2ServerTest.scala
+++ b/http2-tests/src/test/scala/org/apache/pekko/http/scaladsl/Http2ServerTest.scala
@@ -44,7 +44,7 @@ object Http2ServerTest extends App {
     pekko.actor.serialize-messages = off
     #pekko.actor.default-dispatcher.throughput = 1000
     pekko.actor.default-dispatcher.fork-join-executor.parallelism-max=8
-    pekko.http.server.preview.enable-http2 = true
+    pekko.http.server.enable-http2 = true
                                                    """)
   implicit val system: ActorSystem = ActorSystem("ServerTest", testConf)
   implicit val ec: ExecutionContext = system.dispatcher

From 17b6de1fa2c1504dfa03c2d07f3f2942d800243f Mon Sep 17 00:00:00 2001
From: PJ Fanning <pjfanning@users.noreply.github.com>
Date: Fri, 3 Oct 2025 06:46:23 +0100
Subject: [PATCH 2/5] scalafmt

---
 http-core/src/main/resources/reference.conf            |  3 +++
 .../pekko/http/javadsl/settings/ServerSettings.scala   |  1 +
 .../http/scaladsl/settings/PreviewServerSettings.scala |  2 +-
 .../pekko/http/scaladsl/settings/ServerSettings.scala  | 10 ++++++----
 4 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/http-core/src/main/resources/reference.conf b/http-core/src/main/resources/reference.conf
index 12c7c3a18..fb2c89a29 100644
--- a/http-core/src/main/resources/reference.conf
+++ b/http-core/src/main/resources/reference.conf
@@ -24,6 +24,9 @@ pekko.http {
     # will be enabled to use HTTP/2.
     #
     # `Http().newServerAt(...).bindFlow` and `connectionSource()` are not supported.
+    #
+    # Note that this setting is intended to replace `pekko.http.server.preview.enable-http2`
+    # but that setting is still supported for compatibility reasons.
     enable-http2 = off
 
     # "PREVIEW" features that are not yet fully production ready.
diff --git a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
index 013507adf..36a23b7b2 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
@@ -56,6 +56,7 @@ import scala.concurrent.duration.{ Duration, FiniteDuration }
   def getTerminationDeadlineExceededResponse: pekko.http.javadsl.model.HttpResponse
   def getParsingErrorHandler: String
   def getStreamCancellationDelay: FiniteDuration
+
   /**
    * Configures the Http extension to bind using HTTP/2 if given an
    * [[pekko.http.scaladsl.HttpsConnectionContext]]. Otherwise binds as plain HTTP.
diff --git a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala
index 5bcac07b7..5c513538f 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala
@@ -24,7 +24,7 @@ import com.typesafe.config.Config
  * Options that are in "preview" or "early access" mode.
  * These options may change and/or be removed within patch releases
  * without early notice (e.g. by moving them into a stable supported place).
- * 
+ *
  * @deprecated PreviewServerSettings is deprecated, use pekko.http.scaladsl.settings.ServerSettings instead (since 2.0.0)
  */
 @ApiMayChange @DoNotInherit
diff --git a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
index 4b788b3fa..cf8f717ca 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
@@ -60,17 +60,19 @@ abstract class ServerSettings private[pekko] () extends pekko.http.javadsl.setti
   def terminationDeadlineExceededResponse: HttpResponse
   def parsingErrorHandler: String
   def streamCancellationDelay: FiniteDuration
+
   /**
-    * @since 2.0.0
-    */
+   * @since 2.0.0
+   */
   def enableHttp2: Boolean
 
   /* Java APIs */
 
   override def getBacklog = this.backlog
+
   /**
-    * @deprecated the preview server settings are now integrated into the main server settings (since 2.0.0)
-    */
+   * @deprecated the preview server settings are now integrated into the main server settings (since 2.0.0)
+   */
   @Deprecated
   @deprecated("the preview server settings are now integrated into the main server settings", "2.0.0")
   override def getPreviewServerSettings: pekko.http.javadsl.settings.PreviewServerSettings = this.previewServerSettings

From a90fd70aa9434f7a0e7d3d9ea2c15087b9996098 Mon Sep 17 00:00:00 2001
From: PJ Fanning <pjfanning@users.noreply.github.com>
Date: Fri, 3 Oct 2025 07:01:46 +0100
Subject: [PATCH 3/5] mima

---
 .../http2-out-of-preview.excludes             | 20 +++++++++++++++++++
 .../settings/PreviewServerSettings.scala      |  4 ++--
 .../javadsl/settings/ServerSettings.scala     |  4 ++--
 .../settings/PreviewServerSettings.scala      |  4 ++--
 .../scaladsl/settings/ServerSettings.scala    | 10 +++++-----
 5 files changed, 31 insertions(+), 11 deletions(-)
 create mode 100644 http-core/src/main/mima-filters/1.3.x.backwards.excludes/http2-out-of-preview.excludes

diff --git a/http-core/src/main/mima-filters/1.3.x.backwards.excludes/http2-out-of-preview.excludes b/http-core/src/main/mima-filters/1.3.x.backwards.excludes/http2-out-of-preview.excludes
new file mode 100644
index 000000000..61efca5c8
--- /dev/null
+++ b/http-core/src/main/mima-filters/1.3.x.backwards.excludes/http2-out-of-preview.excludes
@@ -0,0 +1,20 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# HTTP/2 is no longer in preview
+ProblemFilters.exclude[ReversedMissingMethodProblem]("org.apache.pekko.http.javadsl.settings.ServerSettings.enableHttp2")
+ProblemFilters.exclude[ReversedMissingMethodProblem]("org.apache.pekko.http.scaladsl.settings.ServerSettings.enableHttp2")
diff --git a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/PreviewServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/PreviewServerSettings.scala
index 44de8d4c3..c3c148c3a 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/PreviewServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/PreviewServerSettings.scala
@@ -26,11 +26,11 @@ import com.typesafe.config.Config
  * These options may change and/or be removed within patch releases
  * without early notice (e.g. by moving them into a stable supported place).
  *
- * @deprecated PreviewServerSettings is deprecated, use pekko.http.javadsl.settings.ServerSettings instead (since 2.0.0)
+ * @deprecated PreviewServerSettings is deprecated, use pekko.http.javadsl.settings.ServerSettings instead (since 1.3.0)
  */
 @ApiMayChange @DoNotInherit
 @Deprecated
-@deprecated("PreviewServerSettings is deprecated, use pekko.http.javadsl.settings.ServerSettings instead", "2.0.0")
+@deprecated("PreviewServerSettings is deprecated, use pekko.http.javadsl.settings.ServerSettings instead", "1.3.0")
 abstract class PreviewServerSettings private[pekko] () { self: PreviewServerSettingsImpl =>
 
   /**
diff --git a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
index 36a23b7b2..51f3df32c 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
@@ -34,7 +34,7 @@ import scala.concurrent.duration.{ Duration, FiniteDuration }
  */
 @DoNotInherit abstract class ServerSettings { self: ServerSettingsImpl =>
   def getServerHeader: Optional[Server]
-  @deprecated("the preview server settings are now integrated into the main server settings", "2.0.0")
+  @deprecated("the preview server settings are now integrated into the main server settings", "1.3.0")
   def getPreviewServerSettings: PreviewServerSettings
   def getTimeouts: ServerSettings.Timeouts
   def getMaxConnections: Int
@@ -67,7 +67,7 @@ import scala.concurrent.duration.{ Duration, FiniteDuration }
 
   def withServerHeader(newValue: Optional[Server]): ServerSettings =
     self.copy(serverHeader = newValue.toScala.map(_.asScala))
-  @deprecated("the preview server settings are now integrated into the main server settings", "2.0.0")
+  @deprecated("the preview server settings are now integrated into the main server settings", "1.3.0")
   def withPreviewServerSettings(newValue: PreviewServerSettings): ServerSettings =
     self.copy(previewServerSettings = newValue.asScala)
   def withTimeouts(newValue: ServerSettings.Timeouts): ServerSettings = self.copy(timeouts = newValue.asScala)
diff --git a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala
index 5c513538f..9de8d7beb 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/PreviewServerSettings.scala
@@ -25,10 +25,10 @@ import com.typesafe.config.Config
  * These options may change and/or be removed within patch releases
  * without early notice (e.g. by moving them into a stable supported place).
  *
- * @deprecated PreviewServerSettings is deprecated, use pekko.http.scaladsl.settings.ServerSettings instead (since 2.0.0)
+ * @deprecated PreviewServerSettings is deprecated, use pekko.http.scaladsl.settings.ServerSettings instead (since 1.3.0)
  */
 @ApiMayChange @DoNotInherit
-@deprecated("PreviewServerSettings is deprecated, use pekko.http.scaladsl.settings.ServerSettings instead", "2.0.0")
+@deprecated("PreviewServerSettings is deprecated, use pekko.http.scaladsl.settings.ServerSettings instead", "1.3.0")
 abstract class PreviewServerSettings private[pekko] ()
     extends org.apache.pekko.http.javadsl.settings.PreviewServerSettings {
   self: PreviewServerSettingsImpl =>
diff --git a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
index cf8f717ca..520035f09 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
@@ -62,7 +62,7 @@ abstract class ServerSettings private[pekko] () extends pekko.http.javadsl.setti
   def streamCancellationDelay: FiniteDuration
 
   /**
-   * @since 2.0.0
+   * @since 1.3.0
    */
   def enableHttp2: Boolean
 
@@ -71,10 +71,10 @@ abstract class ServerSettings private[pekko] () extends pekko.http.javadsl.setti
   override def getBacklog = this.backlog
 
   /**
-   * @deprecated the preview server settings are now integrated into the main server settings (since 2.0.0)
+   * @deprecated the preview server settings are now integrated into the main server settings (since 1.3.0)
    */
   @Deprecated
-  @deprecated("the preview server settings are now integrated into the main server settings", "2.0.0")
+  @deprecated("the preview server settings are now integrated into the main server settings", "1.3.0")
   override def getPreviewServerSettings: pekko.http.javadsl.settings.PreviewServerSettings = this.previewServerSettings
   override def getDefaultHostHeader = this.defaultHostHeader.asJava
   override def getPipeliningLimit = this.pipeliningLimit
@@ -99,10 +99,10 @@ abstract class ServerSettings private[pekko] () extends pekko.http.javadsl.setti
 
   // override for more specific return type
   /**
-   * @deprecated the preview server settings are now integrated into the main server settings (since 2.0.0)
+   * @deprecated the preview server settings are now integrated into the main server settings (since 1.3.0)
    */
   @Deprecated
-  @deprecated("the preview server settings are now integrated into the main server settings", "2.0.0")
+  @deprecated("the preview server settings are now integrated into the main server settings", "1.3.0")
   def withPreviewServerSettings(newValue: PreviewServerSettings): ServerSettings =
     self.copy(previewServerSettings = newValue)
   override def withMaxConnections(newValue: Int): ServerSettings = self.copy(maxConnections = newValue)

From 49100b6cca9dcc91eb36f1f910681ca5e97765d8 Mon Sep 17 00:00:00 2001
From: PJ Fanning <pjfanning@users.noreply.github.com>
Date: Fri, 3 Oct 2025 07:06:19 +0100
Subject: [PATCH 4/5] scaladoc

---
 .../apache/pekko/http/javadsl/settings/ServerSettings.scala | 6 ++++++
 .../pekko/http/scaladsl/settings/ServerSettings.scala       | 3 +++
 2 files changed, 9 insertions(+)

diff --git a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
index 51f3df32c..1f9dcc1db 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/javadsl/settings/ServerSettings.scala
@@ -60,6 +60,8 @@ import scala.concurrent.duration.{ Duration, FiniteDuration }
   /**
    * Configures the Http extension to bind using HTTP/2 if given an
    * [[pekko.http.scaladsl.HttpsConnectionContext]]. Otherwise binds as plain HTTP.
+   *
+   * @since 1.3.0
    */
   def enableHttp2: Boolean
 
@@ -95,6 +97,10 @@ import scala.concurrent.duration.{ Duration, FiniteDuration }
   def withParsingErrorHandler(newValue: String): ServerSettings = self.copy(parsingErrorHandler = parsingErrorHandler)
   def withStreamCancellationDelay(newValue: FiniteDuration): ServerSettings =
     self.copy(streamCancellationDelay = newValue)
+
+  /**
+   * @since 1.3.0
+   */
   def withEnableHttp2(newValue: Boolean): ServerSettings = self.copy(enableHttp2 = newValue)
 }
 
diff --git a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
index 520035f09..79599fa86 100644
--- a/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
+++ b/http-core/src/main/scala/org/apache/pekko/http/scaladsl/settings/ServerSettings.scala
@@ -62,6 +62,9 @@ abstract class ServerSettings private[pekko] () extends pekko.http.javadsl.setti
   def streamCancellationDelay: FiniteDuration
 
   /**
+   * Configures the Http extension to bind using HTTP/2 if given an
+   * [[pekko.http.scaladsl.HttpsConnectionContext]]. Otherwise binds as plain HTTP.
+   *
    * @since 1.3.0
    */
   def enableHttp2: Boolean

From acdf7ee146b0d59209d3084f01083556a7539997 Mon Sep 17 00:00:00 2001
From: PJ Fanning <pjfanning@users.noreply.github.com>
Date: Fri, 3 Oct 2025 10:27:41 +0100
Subject: [PATCH 5/5] Update ServerSettingsSpec.scala

---
 .../settings/ServerSettingsSpec.scala         | 33 +++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/http-core/src/test/scala/org/apache/pekko/http/scaladsl/settings/ServerSettingsSpec.scala b/http-core/src/test/scala/org/apache/pekko/http/scaladsl/settings/ServerSettingsSpec.scala
index 20197cb52..9c1b72a63 100644
--- a/http-core/src/test/scala/org/apache/pekko/http/scaladsl/settings/ServerSettingsSpec.scala
+++ b/http-core/src/test/scala/org/apache/pekko/http/scaladsl/settings/ServerSettingsSpec.scala
@@ -13,6 +13,7 @@
 
 package org.apache.pekko.http.scaladsl.settings
 
+import com.typesafe.config.ConfigFactory
 import org.apache.pekko.testkit.PekkoSpec
 
 class ServerSettingsSpec extends PekkoSpec {
@@ -32,5 +33,37 @@ class ServerSettingsSpec extends PekkoSpec {
       }
       e.getMessage should include("does not contain the server-specific settings")
     }
+    "default enableHttp2 to false" in {
+      val serverSettings = ServerSettings(system)
+      serverSettings.enableHttp2 should ===(false)
+    }
+    "set enableHttp2 to true if preview.enable-http2 is on" in {
+      val cfg = ConfigFactory.parseString("""
+        pekko.http.server {
+          preview.enable-http2 = on
+        }
+      """).withFallback(system.settings.config)
+      val serverSettings = ServerSettings(cfg)
+      serverSettings.enableHttp2 should ===(true)
+    }
+    "set enableHttp2 to true if enable-http2 is on" in {
+      val cfg = ConfigFactory.parseString("""
+        pekko.http.server {
+          enable-http2 = on
+        }
+      """).withFallback(system.settings.config)
+      val serverSettings = ServerSettings(cfg)
+      serverSettings.enableHttp2 should ===(true)
+    }
+    "set enableHttp2 to true if enable-http2 is on and preview.enable-http2 is off" in {
+      val cfg = ConfigFactory.parseString("""
+        pekko.http.server {
+          enable-http2 = on
+          preview.enable-http2 = off
+        }
+      """).withFallback(system.settings.config)
+      val serverSettings = ServerSettings(cfg)
+      serverSettings.enableHttp2 should ===(true)
+    }
   }
 }