Initial 3.0.0-beta1 release - migrates from Akka to Pekko nightly build

Quickstart.sc

@@ -7,7 +7,7 @@
 */
 import $ivy.`io.skuber::skuber:2.0.10`, skuber._, skuber.json.format._
 
-import akka.actor.ActorSystem
+import org.apache.pekko.actor.ActorSystem
 import api.Configuration
 import scala.concurrent.Future
 import scala.util.{Success, Failure}

README.md

@@ -21,12 +21,12 @@ See the [programming guide](docs/GUIDE.md) for more details.
 
 ## Example
 
-This example lists pods in `kube-system` namespace:
+This example (for Skuber 3.x) lists pods in `kube-system` namespace:
 
   ```scala
   import skuber._
   import skuber.json.format._
-  import akka.actor.ActorSystem
+  import org.apache.pekko.actor.ActorSystem
   import scala.util.{Success, Failure}
 
   implicit val system = ActorSystem()
@@ -107,31 +107,38 @@ For other Kubernetes setups, see the [configuration guide](docs/Configuration.md
 
 ## Prerequisites
 
-- Java 8
+- Java 8 or higher
 - Kubernetes cluster
 
-A Kubernetes cluster is needed at runtime. For local development purposes, minikube is recommended.
-To get minikube follow the instructions [here](https://github.com/kubernetes/minikube)
+A Kubernetes cluster is needed at runtime. For local development purposes, `kind` is recommended.
+To install `kind` follow the instructions [here](https://kind.sigs.k8s.io/docs/user/quick-start/).
 
 ## Release
 
-You can use the latest release (for 2.12 or 2.13) by adding to your build:
+You can use the latest full 2.x release (for Scala 2.12 or 2.13) by adding to your build:
 
 ```sbt
 libraryDependencies += "io.skuber" %% "skuber" % "2.6.7"
 ```
 
-Meanwhile users of skuber v1 can continue to use the final v1.x release, which is available only on Scala 2.11:
+Meanwhile a pre-release of 3.x (which moves away from Akka to Pekko) is now available:
 
 ```sbt
-libraryDependencies += "io.skuber" % "skuber_2.11" % "1.7.1"
+libraryDependencies += "io.skuber" % "skuber" % "3.0.0-beta1"
 ```
 
-NOTE: Skuber 2 supports Scala 2.13 since v2.4.0 - support for Scala 2.11 has now been removed since v2.6.0.
+The pre-release currently uses a nightly build of Pekko as no full release is yet available - as such it is not recommended for production use but can be used for testing migration of your stack away from Akka. 
+A full release of Skuber 3.x will be made available when Pekko has an official release.
 
-## Migrating to release v2
+NOTE: Skuber supports Scala 2.13 since 2.4.0 - support for Scala 2.11 has now been removed since 2.6.0.
 
-If you have an application using the legacy version v1 of Skuber and want to move to v2, then check out the [migration guide](docs/MIGRATION_1-to-2.md).
+## Migrating from release 2.x to 3.x
+
+Skuber 3.x is mostly backwards-compatible with 2.x, except that it replaces all of its uses of Akka with [Pekko](https://github.com/apache/incubator-pekko). 
+In practice this normally requires minimal changes to your application to migrate to 3.x:
+
+- rename Akka imports e.g. `import akka.actor.ActorSystem` becomes `import org.apache.pekko.actor.ActorSystem`
+- rename any `akka` section(s) of your application configuration (`application.conf` file) that relate to skuber to `pekko`.
 
 ## Building
 
@@ -141,7 +148,6 @@ Building the library from source is very straightforward. Simply run `sbt test`i
 
 This code is licensed under the Apache V2.0 license, a copy of which is included [here](LICENSE.txt).
 
-## IMPORTANT: Akka License Model Changes
-
-Lightbend have moved Akka versions starting from 2.7.x from an Apache 2.0 to BSL license. Skuber currently uses Akka 2.6.x and it is not planned to move to a BSL licensed Akka version - instead it is planned to migrate Skuber to the Apache Pekko open-source fork once it has a full release.
+## IMPORTANT: Akka License Model Changes And Pekko Migration
 
+Lightbend have moved Akka versions starting from 2.7.x from an Apache 2.0 to BSL license. Skuber 2.x uses Akka 2.6.x and it is not planned to move to a BSL licensed Akka version - instead it is planned that Skuber 3.x will move from Akka to the Apache Pekko open-source fork.

build.sbt

@@ -1,84 +1,93 @@
 
-resolvers += "Typesafe Releases" at "https://repo.typesafe.com/typesafe/releases/"
+// resolvers += "Typesafe Releases" at "https://repo.typesafe.com/typesafe/releases/"
 
-val akkaVersion = "2.6.19"
+val pekkoGroup = "org.apache.pekko"
 
-val scalaCheck = "org.scalacheck" %% "scalacheck" % "1.15.4"
-val specs2 = "org.specs2" %% "specs2-core" % "4.17.0"
-val scalaTest = "org.scalatest" %% "scalatest" % "3.2.14"
+val pekkoVersion = "0.0.0+26626-3e1231c3-SNAPSHOT"
+val pekkoHttpVersion = "0.0.0+4332-87421a76-SNAPSHOT"
+
+// the client API request/response handing uses Pekka Http
+val pekkoHttp = pekkoGroup %% "pekko-http" % pekkoHttpVersion
+
+// The `watch` and some other functionality uses Pekko streams
+val pekkoStreams = pekkoGroup %% "pekko-stream" % pekkoVersion
+val pekkoStreamsTestkit = pekkoGroup %% "pekko-stream-testkit" % pekkoVersion % Test
+
+// Skuber uses Pekko logging, so the examples config uses the Pekko slf4j logger with logback backend
+val pekkoSlf4j = pekkoGroup %% "pekko-slf4j" % pekkoVersion
+val logback = "ch.qos.logback" % "logback-classic" % "1.4.6" % Runtime
+
+val scalaCheck = "org.scalacheck" %% "scalacheck" % "1.17.0"
+val specs2 = "org.specs2" %% "specs2-core" % "4.19.2"
+val scalaTest = "org.scalatest" %% "scalatest" % "3.2.15"
 val mockito = "org.mockito" % "mockito-core" % "4.6.1"
-val scalaTestMockito = "org.scalatestplus" %% "mockito-4-6" % "3.2.14.0"
-val akkaStreamTestKit = "com.typesafe.akka" %% "akka-stream-testkit" % akkaVersion
+val scalaTestMockito = "org.scalatestplus" %% "mockito-4-6" % "3.2.15.0"
 
 val snakeYaml =  "org.yaml" % "snakeyaml" % "2.0"
 val commonsIO = "commons-io" % "commons-io" % "2.11.0"
 val commonsCodec = "commons-codec" % "commons-codec" % "1.15"
 
-// the client API request/response handing uses Akka Http
-val akkaHttp = "com.typesafe.akka" %% "akka-http" % "10.2.9"
-val akkaStream = "com.typesafe.akka" %% "akka-stream" % akkaVersion
-val akka = "com.typesafe.akka" %% "akka-actor" % akkaVersion
-
-// Skuber uses akka logging, so the examples config uses the akka slf4j logger with logback backend
-val akkaSlf4j = "com.typesafe.akka" %% "akka-slf4j" % akkaVersion
-val logback = "ch.qos.logback" % "logback-classic" % "1.4.4" % Runtime
-
 // the Json formatters are based on Play Json
-val playJson = "com.typesafe.play" %% "play-json" % "2.9.3"
+val playJson = "com.typesafe.play" %% "play-json" % "2.9.4"
 
 // Need Java 8 or later as the java.time package is used to represent K8S timestamps
 scalacOptions += "-target:jvm-1.8"
 
-scalacOptions in Test ++= Seq("-Yrangepos")
+Test / scalacOptions ++= Seq("-Yrangepos")
 
-ThisBuild / version := "2.6.7"
+ThisBuild / version := "3.0.0-beta1"
 
 sonatypeProfileName := "io.skuber"
 
-publishMavenStyle in ThisBuild := true
+ThisBuild / publishMavenStyle := true
 
-licenses in ThisBuild := Seq("APL2" -> url("http://www.apache.org/licenses/LICENSE-2.0.txt"))
+ThisBuild / licenses := Seq("APL2" -> url("http://www.apache.org/licenses/LICENSE-2.0.txt"))
 
-homepage in ThisBuild := Some(url("https://github.com/doriordan"))
+ThisBuild / homepage := Some(url("https://github.com/doriordan"))
 
-scmInfo in ThisBuild := Some(
+ThisBuild / scmInfo := Some(
   ScmInfo(
     url("https://github.com/doriordan/skuber"),
     "scm:[email protected]:doriordan/skuber.git"
   )
 )
 
-developers in ThisBuild := List(Developer(id="doriordan", name="David ORiordan", email="[email protected]", url=url("https://github.com/doriordan")))
+ThisBuild / developers := List(Developer(id="doriordan", name="David ORiordan", email="[email protected]", url=url("https://github.com/doriordan")))
 
 lazy val commonSettings = Seq(
   organization := "io.skuber",
   crossScalaVersions := Seq("2.12.17", "2.13.10"),
   scalaVersion := "2.13.10",
   publishTo :=  sonatypePublishToBundle.value,
   pomIncludeRepository := { _ => false },
-  Test / classLoaderLayeringStrategy := ClassLoaderLayeringStrategy.Flat
+  Test / classLoaderLayeringStrategy := ClassLoaderLayeringStrategy.Flat,
+  resolvers += "Apache Pekko Snapshots" at "https://repository.apache.org/content/groups/snapshots"
 )
 
 lazy val skuberSettings = Seq(
   name := "skuber",
   libraryDependencies ++= Seq(
-    akkaHttp, akkaStream, playJson, snakeYaml, commonsIO, commonsCodec,
+    pekkoHttp, pekkoStreams, playJson, snakeYaml, commonsIO, commonsCodec,
     scalaCheck % Test, specs2 % Test, mockito % Test, scalaTestMockito % Test,
-    akkaStreamTestKit % Test, scalaTest % Test
+    pekkoStreamsTestkit, scalaTest % Test
   ).map(_.exclude("commons-logging", "commons-logging"))
 )
 
+// This explicit Pekko dependency for the example build is not strictly necessary (the necessary dependencies will be transitively
+// inherited from skuber dependency anyway) but clients might opt to explicitly specify such dependencies, for example to override version.
+val pekkoActors = pekkoGroup %% "pekko-actor" % pekkoVersion
+
 lazy val examplesSettings = Seq(
   name := "skuber-examples",
-  libraryDependencies ++= Seq(akka, akkaSlf4j, logback)
+  libraryDependencies ++= Seq(pekkoActors, pekkoSlf4j, logback)
 )
 
-// by default run the guestbook example when executing a fat examples JAR
+// by default run the deployment examples when executing a fat examples JAR
 lazy val examplesAssemblySettings = Seq(
-  mainClass in assembly := Some("skuber.examples.guestbook.Guestbook")
+  assembly / mainClass := Some("skuber.examples.deployment.DeploymentExamples")
 )
 
-publishArtifact in root := false
+root / publishArtifact := false
 
 lazy val root = (project in file("."))
   .settings(commonSettings: _*)
@@ -90,11 +99,11 @@ lazy val skuber= (project in file("client"))
     commonSettings,
     skuberSettings,
     Defaults.itSettings,
-    libraryDependencies += scalaTest % "it"
+    libraryDependencies += scalaTest % "it",
   )
 
 lazy val examples = (project in file("examples"))
   .settings(commonSettings: _*)
   .settings(examplesSettings: _*)
   .settings(examplesAssemblySettings: _*)
-  .dependsOn(skuber)
+  .dependsOn(skuber)

client/src/it/scala/skuber/CustomResourceBetaSpec.scala

@@ -1,7 +1,7 @@
 package skuber
 
-import akka.stream._
-import akka.stream.scaladsl._
+import org.apache.pekko.stream._
+import org.apache.pekko.stream.scaladsl._
 import org.scalatest.concurrent.Eventually
 import org.scalatest.matchers.should.Matchers
 import play.api.libs.json._

client/src/it/scala/skuber/CustomResourceSpec.scala

@@ -1,7 +1,7 @@
 package skuber
 
-import akka.stream._
-import akka.stream.scaladsl._
+import org.apache.pekko.stream._
+import org.apache.pekko.stream.scaladsl._
 import skuber.apiextensions.v1.CustomResourceDefinition
 import org.scalatest.matchers.should.Matchers
 import org.scalatest.concurrent.Eventually

client/src/it/scala/skuber/ExecSpec.scala

@@ -1,7 +1,7 @@
 package skuber
 
-import akka.Done
-import akka.stream.scaladsl.{Sink, Source}
+import org.apache.pekko.Done
+import org.apache.pekko.stream.scaladsl.{Sink, Source}
 import org.scalatest.BeforeAndAfterAll
 import org.scalatest.concurrent.Eventually
 import org.scalatest.matchers.should.Matchers

client/src/it/scala/skuber/K8SFixture.scala

@@ -1,6 +1,6 @@
 package skuber
 
-import akka.actor.ActorSystem
+import org.apache.pekko.actor.ActorSystem
 import org.scalatest.FutureOutcome
 import com.typesafe.config.ConfigFactory
 import org.scalatest.flatspec.FixtureAsyncFlatSpec

client/src/it/scala/skuber/PodLogSpec.scala

@@ -2,7 +2,7 @@ package skuber
 
 import java.time.ZonedDateTime
 
-import akka.stream.scaladsl.TcpIdleTimeoutException
+import org.apache.pekko.stream.scaladsl.TcpIdleTimeoutException
 import com.typesafe.config.ConfigFactory
 import org.scalatest.BeforeAndAfterAll
 import org.scalatest.concurrent.Eventually

client/src/it/scala/skuber/WatchContinuouslySpec.scala

@@ -1,7 +1,7 @@
 package skuber
 
-import akka.stream.KillSwitches
-import akka.stream.scaladsl.{Keep, Sink}
+import org.apache.pekko.stream.KillSwitches
+import org.apache.pekko.stream.scaladsl.{Keep, Sink}
 import org.scalatest.matchers.should.Matchers
 import org.scalatest.concurrent.{Eventually, ScalaFutures}
 import org.scalatest.time.{Seconds, Span}

client/src/main/resources/reference.conf

@@ -1,7 +1,7 @@
 skuber {
 
-  akka {
-    # The ID of the dispatcher to use by Skuber. If undefined or empty the default Akka dispatcher is used.
+  pekko {
+    # The ID of the dispatcher to use by Skuber. If undefined or empty the default Pekko dispatcher is used.
     dispatcher = ""
   }
 

client/src/main/scala/skuber/api/client/KubernetesClient.scala

@@ -1,7 +1,7 @@
 package skuber.api.client
 
-import akka.stream.scaladsl.{Sink, Source}
-import akka.util.ByteString
+import org.apache.pekko.stream.scaladsl.{Sink, Source}
+import org.apache.pekko.util.ByteString
 import play.api.libs.json.{Writes,Format}
 import skuber.{DeleteOptions, HasStatusSubresource, LabelSelector, ListOptions, ListResource, ObjectResource, Pod, ResourceDefinition, Scale}
 import skuber.api.patch.Patch
@@ -176,7 +176,7 @@ trait KubernetesClient {
     * timeouts - the source returned by this method will complete in the presence of such timeouts or other disconnections.
     * @param obj the name of the object to watch
     * @tparam O the type of the object to watch e.g. Pod, Deployment
-    * @return A future containing an Akka streams Source of WatchEvents that will be emitted
+    * @return A future containing a Pekko streams Source of WatchEvents that will be emitted
     */
   def watch[O <: ObjectResource](obj: O)(implicit fmt: Format[O], rd: ResourceDefinition[O], lc: LoggingContext): Future[Source[WatchEvent[O], _]]
 
@@ -191,7 +191,7 @@ trait KubernetesClient {
     * be produced for an already existing object followed by events for any future changes.
     * @param bufSize An optional buffer size for the returned on-the-wire representation of each modified object - normally the default is more than enough.
     * @tparam O the type of the resource to watch
-    * @return A future containing an Akka streams Source of WatchEvents that will be emitted
+    * @return A future containing a Pekko streams Source of WatchEvents that will be emitted
     */
   def watch[O <: ObjectResource](name: String, sinceResourceVersion: Option[String] = None, bufSize: Int = 10000)(
     implicit fmt: Format[O], rd: ResourceDefinition[O], lc: LoggingContext): Future[Source[WatchEvent[O], _]]
@@ -207,7 +207,7 @@ trait KubernetesClient {
     * be produced for an already existing object followed by events for any future changes.
     * @param bufSize optional buffer size for each modified object received, normally the default is more than enough
     * @tparam O the type of resource to watch e.g. Pod, Dpeloyment
-    * @return A future containing an Akka streams Source of WatchEvents that will be emitted
+    * @return A future containing a Pekko streams Source of WatchEvents that will be emitted
     */
   def watchAll[O <: ObjectResource](sinceResourceVersion: Option[String] = None, bufSize: Int = 10000)(
     implicit fmt: Format[O], rd: ResourceDefinition[O], lc: LoggingContext): Future[Source[WatchEvent[O], _]]
@@ -217,7 +217,7 @@ trait KubernetesClient {
     * events on any updates to the object even if the server times out, by transparently restarting the watch as needed.
     * @param obj  the object resource to watch
     * @tparam O the type of the resource e.g Pod
-    * @return  A future containing an Akka streams Source of WatchEvents that will be emitted
+    * @return  A future containing a Pekko streams Source of WatchEvents that will be emitted
     */
   def watchContinuously[O <: ObjectResource](obj: O)(implicit fmt: Format[O], rd: ResourceDefinition[O], lc: LoggingContext): Source[WatchEvent[O], _]
 
@@ -233,7 +233,7 @@ trait KubernetesClient {
     * a single ADDED event will be produced for an already existing object followed by events for any future changes.
     * @param bufSize optional buffer size for received object updates, normally the default is more than enough
     * @tparam O the type of the resource
-    * @return A future containing an Akka streams Source of WatchEvents that will be emitted
+    * @return A future containing a Pekka streams Source of WatchEvents that will be emitted
     */
   def watchContinuously[O <: ObjectResource](name: String, sinceResourceVersion: Option[String] = None, bufSize: Int = 10000)(
     implicit fmt: Format[O], rd: ResourceDefinition[O], lc: LoggingContext): Source[WatchEvent[O], _]
@@ -249,7 +249,7 @@ trait KubernetesClient {
     * a single ADDED event will be produced for an already existing object followed by events for any future changes.
     * @param bufSize optional buffer size for received object updates, normally the default is more than enough
     * @tparam O the type pf the resource
-    * @return A future containing an Akka streams Source of WatchEvents that will be emitted
+    * @return A future containing a Pekko streams Source of WatchEvents that will be emitted
     */
   def watchAllContinuously[O <: ObjectResource](sinceResourceVersion: Option[String] = None, bufSize: Int = 10000)(
     implicit fmt: Format[O], rd: ResourceDefinition[O], lc: LoggingContext): Source[WatchEvent[O], _]
@@ -262,7 +262,7 @@ trait KubernetesClient {
   * ensures a watch is always requested on the server.
   * @param bufsize optional buffer size for received object updates, normally the default is more than enough
   * @tparam O the resource type to watch
-  * @return A future containing an Akka streams Source of WatchEvents that will be emitted
+  * @return A future containing a Pekko streams Source of WatchEvents that will be emitted
   */
   def watchWithOptions[O <: ObjectResource](options: ListOptions, bufsize: Int = 10000)(
     implicit fmt: Format[O], rd: ResourceDefinition[O], lc: LoggingContext): Source[WatchEvent[O], _]
@@ -320,7 +320,7 @@ trait KubernetesClient {
   def jsonMergePatch[O <: ObjectResource](obj: O, patch: String)(implicit rd: ResourceDefinition[O], fmt: Format[O], lc: LoggingContext): Future[O]
 
   /**
-    * Get the logs from a pod (similar to `kubectl logs ...`). The logs are streamed using an Akka streams source
+    * Get the logs from a pod (similar to `kubectl logs ...`). The logs are streamed using a Pekko streams source
     * @param name the name of the pod
     * @param queryParams optional parameters of the request (for example container name)
     * @param namespace if set this specifies the namespace of the pod (otherwise the configured namespace is used)
@@ -333,9 +333,9 @@ trait KubernetesClient {
     * @param podName the name of the pod
     * @param command the command to execute
     * @param maybeContainerName an optional container name
-    * @param maybeStdin optional Akka Source for sending input to stdin for the command
-    * @param maybeStdout optional Akka Sink to receive output from stdout for the command
-    * @param maybeStderr optional Akka Sink to receive output from stderr for the command
+    * @param maybeStdin optional Pekko Source for sending input to stdin for the command
+    * @param maybeStdout optional Pekko Sink to receive output from stdout for the command
+    * @param maybeStderr optional Pekko Sink to receive output from stderr for the command
     * @param tty optionally set tty on
     * @param maybeClose if set, this can be used to close the connection to the pod by completing the promise
     * @return A future indicating the exec command has been submitted