Add compat module for wire compatibility with Akka

akka-kryo-serialization-pekko-compat/src/main/scala/io/altoo/akka/serialization/kryo/compat/PekkoCompatKryoInitializer.scala

@@ -0,0 +1,20 @@
+package io.altoo.akka.serialization.kryo.compat
+
+import akka.actor.ExtendedActorSystem
+import io.altoo.akka.serialization.kryo.DefaultKryoInitializer
+import io.altoo.akka.serialization.kryo.compat.serializer.CompatActorRefSerializer
+import io.altoo.akka.serialization.kryo.serializer.akka.ByteStringSerializer
+import io.altoo.akka.serialization.kryo.serializer.scala.ScalaKryo
+
+class PekkoCompatKryoInitializer extends DefaultKryoInitializer {
+
+  override def initAkkaSerializer(kryo: ScalaKryo, system: ExtendedActorSystem): Unit = {
+    super.initAkkaSerializer(kryo, system)
+
+    // registering dummy Akka ActorRef to provide wire compatibility
+    kryo.addDefaultSerializer(classOf[org.apache.pekko.actor.ActorRef], new CompatActorRefSerializer(system))
+    kryo.addDefaultSerializer(classOf[org.apache.pekko.actor.RepointableActorRef], new CompatActorRefSerializer(system))
+    // registering dummy Akka ByteString to provide wire compatibility
+    kryo.addDefaultSerializer(classOf[org.apache.pekko.util.ByteString], classOf[ByteStringSerializer])
+  }
+}

akka-kryo-serialization-pekko-compat/src/main/scala/io/altoo/akka/serialization/kryo/compat/TypedPekkoCompatKryoInitializer.scala

@@ -0,0 +1,23 @@
+package io.altoo.akka.serialization.kryo.compat
+
+import akka.actor.{ExtendedActorSystem, typed}
+import io.altoo.akka.serialization.kryo.compat.serializer.{CompatActorRefSerializer, CompatTypedActorRefSerializer}
+import io.altoo.akka.serialization.kryo.serializer.akka.ByteStringSerializer
+import io.altoo.akka.serialization.kryo.serializer.scala.ScalaKryo
+import io.altoo.akka.serialization.kryo.typed.TypedKryoInitializer
+
+class TypedPekkoCompatKryoInitializer extends TypedKryoInitializer {
+
+  override def initAkkaSerializer(kryo: ScalaKryo, typedSystem: typed.ActorSystem[Nothing]): Unit = {
+    super.initAkkaSerializer(kryo, typedSystem)
+
+    // registering dummy Akka ActorRef to provide wire compatibility
+    kryo.addDefaultSerializer(classOf[org.apache.pekko.actor.ActorRef], new CompatActorRefSerializer(typedSystem.classicSystem.asInstanceOf[ExtendedActorSystem]))
+    kryo.addDefaultSerializer(classOf[org.apache.pekko.actor.RepointableActorRef], new CompatActorRefSerializer(typedSystem.classicSystem.asInstanceOf[ExtendedActorSystem]))
+    // registering dummy Akka ByteString to provide wire compatibility
+    kryo.addDefaultSerializer(classOf[org.apache.pekko.util.ByteString], classOf[ByteStringSerializer])
+
+    // registering dummy Akka ActorRef to provide wire compatibility
+    kryo.addDefaultSerializer(classOf[org.apache.pekko.actor.typed.ActorRef[Nothing]], new CompatTypedActorRefSerializer(typedSystem))
+  }
+}

akka-kryo-serialization-pekko-compat/src/main/scala/io/altoo/akka/serialization/kryo/compat/serializer/CompatActorRefSerializer.scala

@@ -0,0 +1,42 @@
+/**
+ * *****************************************************************************
+ * Copyright 2012 Roman Levenstein
+ *
+ * Licensed 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.
+ * ****************************************************************************
+ */
+
+package io.altoo.akka.serialization.kryo.compat.serializer
+
+import com.esotericsoftware.kryo.io.{Input, Output}
+import com.esotericsoftware.kryo.{Kryo, Serializer}
+import akka.actor.{ActorRef, ExtendedActorSystem}
+import akka.serialization.Serialization
+
+/**
+ * Specialized serializer for actor refs.
+ *
+ * @author Roman Levenstein
+ */
+class CompatActorRefSerializer(val system: ExtendedActorSystem) extends Serializer[ActorRef] {
+
+  override def read(kryo: Kryo, input: Input, typ: Class[? <: ActorRef]): ActorRef = {
+    val path = input.readString()
+    val newPath = path.replace("pekko://", "akka://")
+    system.provider.resolveActorRef(newPath)
+  }
+
+  override def write(kryo: Kryo, output: Output, obj: ActorRef): Unit = {
+    output.writeAscii(Serialization.serializedActorPath(obj))
+  }
+}

akka-kryo-serialization-pekko-compat/src/main/scala/io/altoo/akka/serialization/kryo/compat/serializer/CompatTypedActorRefSerializer.scala

@@ -0,0 +1,43 @@
+/**
+ * *****************************************************************************
+ * Copyright 2012 Roman Levenstein
+ *
+ * Licensed 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.
+ * ****************************************************************************
+ */
+
+package io.altoo.akka.serialization.kryo.compat.serializer
+
+import com.esotericsoftware.kryo.io.{Input, Output}
+import com.esotericsoftware.kryo.{Kryo, Serializer}
+import akka.actor.typed.{ActorRef, ActorRefResolver, ActorSystem}
+
+/**
+ * Specialized serializer for typed actor refs.
+ *
+ * @author Arman Bilge
+ */
+class CompatTypedActorRefSerializer(val system: ActorSystem[Nothing]) extends Serializer[ActorRef[Nothing]] {
+
+  private val resolver = ActorRefResolver(system)
+
+  override def read(kryo: Kryo, input: Input, typ: Class[_ <: ActorRef[Nothing]]): ActorRef[Nothing] = {
+    val path = input.readString()
+    val newPath = path.replace("akka://", "pekko://")
+    resolver.resolveActorRef(newPath)
+  }
+
+  override def write(kryo: Kryo, output: Output, obj: ActorRef[Nothing]): Unit = {
+    output.writeAscii(resolver.toSerializationFormat(obj))
+  }
+}

akka-kryo-serialization-pekko-compat/src/main/scala/org/apache/pekko/actor/ActorRef.scala

@@ -0,0 +1,7 @@
+package org.apache.pekko.actor
+
+/**
+ * Dummy class to register a serializer for akka.actor.ActorRef on Pekko system
+ */
+class ActorRef
+class RepointableActorRef

akka-kryo-serialization-pekko-compat/src/main/scala/org/apache/pekko/actor/typed/ActorRef.scala

@@ -0,0 +1,6 @@
+package org.apache.pekko.actor.typed
+
+/**
+ * Dummy class to register a serializer for akka.actor.typed.ActorRef on Pekko system
+ */
+class ActorRef[-T]

akka-kryo-serialization-pekko-compat/src/main/scala/org/apache/pekko/util/ByteString.scala

@@ -0,0 +1,7 @@
+package org.apache.pekko.util
+
+
+/**
+ * Dummy class to register a serializer for akka.util.ByteString on Pekko system
+ */
+class ByteString

akka-kryo-serialization-pekko-compat/src/test/scala/io/altoo/pekko/serialization/kryo/compat/PekkoCompatSerializerTest.scala

@@ -0,0 +1,66 @@
+package io.altoo.pekko.serialization.kryo.compat
+
+import com.typesafe.config.ConfigFactory
+import akka.actor.{Actor, ActorSystem, Props}
+import akka.serialization.SerializationExtension
+import akka.testkit.TestKit
+import io.altoo.akka.serialization.kryo.KryoSerializer
+import io.altoo.testing.SampleMessage
+import org.scalatest.flatspec.AnyFlatSpecLike
+import org.scalatest.matchers.should.Matchers
+import org.scalatest.{BeforeAndAfterAll, Inside}
+
+object PekkoCompatSerializerTest {
+  private val testConfig =
+    """
+      |akka {
+      |  actor {
+      |    serializers {
+      |      kryo = "io.altoo.akka.serialization.kryo.KryoSerializer"
+      |    }
+      |    serialization-bindings {
+      |      "org.apache.pekko.actor.ActorRef" = kryo
+      |      "akka.actor.ActorRef" = kryo
+      |      "io.altoo.testing.SampleMessage" = kryo
+      |    }
+      |  }
+      |}
+      |akka-kryo-serialization {
+      |  trace = true
+      |  id-strategy = "default"
+      |  implicit-registration-logging = true
+      |  post-serialization-transformations = off
+      |
+      |  kryo-initializer = "io.altoo.akka.serialization.kryo.compat.PekkoCompatKryoInitializer"
+      |}
+      |""".stripMargin
+
+  // serialized io.altoo.testing.SampleMessage(actorRef: org.apache.pekko.actor.ActorRef) with pekko-kryo-serialization
+  private val pekkoActorRefSerialized = Array[Byte](1, 0, 105, 111, 46, 97, 108, 116, 111, 111, 46, 116, 101, 115, 116, 105, 110, 103, 46, 83, 97, 109, 112, 108, 101, 77, 101, 115, 115, 97,
+    103, -27, 1, 1, 1, 111, 114, 103, 46, 97, 112, 97, 99, 104, 101, 46, 112, 101, 107, 107, 111, 46, 97, 99, 116, 111, 114, 46, 82, 101, 112, 111, 105, 110, 116, 97, 98, 108, 101, 65, 99,
+    116, 111, 114, 82, 101, -26, 1, 112, 101, 107, 107, 111, 58, 47, 47, 116, 101, 115, 116, 83, 121, 115, 116, 101, 109, 47, 117, 115, 101, 114, 47, 115, 97, 109, 112, 108, 101, 65, 99, 116,
+    111, 114, 35, 56, 48, 52, 54, 54, 57, 49, 52, -79)
+}
+
+class PekkoCompatSerializerTest extends TestKit(ActorSystem("testSystem", ConfigFactory.parseString(PekkoCompatSerializerTest.testConfig).withFallback(ConfigFactory.load())))
+    with AnyFlatSpecLike with Matchers with Inside with BeforeAndAfterAll {
+
+  private val serialization = SerializationExtension(system)
+
+  override protected def afterAll(): Unit = shutdown(system)
+
+  behavior of "ActorRefSerializer"
+
+  it should "deserialize actorRef from Pekko" in {
+    // create actor with path to not get deadLetter ref
+    system.actorOf(Props(new Actor { def receive: Receive = PartialFunction.empty }), "sampleActor")
+
+    val serializer = serialization.serializerFor(classOf[SampleMessage])
+    serializer shouldBe a[KryoSerializer]
+
+    // deserialize
+    val deserialized = serializer.fromBinary(PekkoCompatSerializerTest.pekkoActorRefSerialized)
+    deserialized shouldBe a[SampleMessage]
+    deserialized.asInstanceOf[SampleMessage].actorRef.path.toString shouldBe "akka://testSystem/user/sampleActor"
+  }
+}

akka-kryo-serialization-pekko-compat/src/test/scala/io/altoo/testing/SampleMessage.scala

@@ -0,0 +1,6 @@
+package io.altoo.testing
+
+import akka.actor.ActorRef
+
+// Mirror class using Pekko ActorRef instead of Akka ActorRef
+case class SampleMessage(actorRef: ActorRef) extends Serializable

build.sbt

@@ -32,7 +32,7 @@ lazy val root: Project = project.in(file("."))
     .settings(publish / skip := true)
     .settings(OsgiKeys.privatePackage := Nil)
     .settings(OsgiKeys.exportPackage := Seq("io.altoo.*"))
-    .aggregate(core, typed)
+    .aggregate(core, typed, pekkoCompat)
 
 lazy val core: Project = Project("akka-kryo-serialization", file("akka-kryo-serialization"))
     .settings(moduleSettings)
@@ -59,6 +59,12 @@ lazy val typed: Project = Project("akka-kryo-serialization-typed", file("akka-kr
     .settings(libraryDependencies ++= typedDeps ++ testingDeps)
     .dependsOn(core)
 
+lazy val pekkoCompat: Project = Project("akka-kryo-serialization-pekko-compat", file("akka-kryo-serialization-pekko-compat"))
+  .settings(moduleSettings)
+  .settings(description := "akka-serialization implementation using kryo - extension for improved wire compatibility with Pekko")
+  .settings(libraryDependencies ++= testingDeps)
+  .dependsOn(core, typed)
+
 
 // Dependencies
 lazy val coreDeps = Seq(

migration-guide.md

@@ -1,6 +1,26 @@
 akka-kryo-serialization - migration guide
 =========================================
 
+Migration from akka-kryo-serialization to pekko-kryo-serialization
+-----------------------------
+* You should upgrade to akka-kryo-serialization 2.5.x before migrating to pekko-kryo-serialization.
+* To support efforts for live migration from Akka to Pekko, compat modules are available in both Akka and Pekko Kryo Serialization to help with wire compatibility of custom messages containing ActorRefs and ByteStrings.
+  ```
+  # on Pekko
+  libraryDependencies += "io.altoo" %% "pekko-kryo-serialization-akka-compat" % "1.0.1"
+
+  # on Akka
+  libraryDependencies += "io.altoo" %% "pekko-kryo-serialization-akka-compat" % "2.5.2"
+  ```
+  Then configure (or derive from if using a custom initializer) `AkkaCompatKryoInitializer` on Pekko, and `PekkoCompatKryoInitializer` on Akka.
+  ```
+  # on Pekko
+  pekko-kryo-serialization.kryo-initializer = "io.altoo.pekko.serialization.kryo.compat.AkkaCompatKryoInitializer"
+
+  # on Akka
+  kka-kryo-serialization.kryo-initializer = "io.altoo.akka.serialization.kryo.compat.PekkoCompatKryoInitializer"
+  ```
+
 Migration from 2.4.x to 2.5.x
 -----------------------------
 * `EnumerationSerializer` has been deprecated with 2.4.2, with 2.5.0 default serializer for `scala.Enumeration` has been switched to `EnumerationNameSerializer`, which is not backwards compatible.