feat: implementation of scala fibonacci sample

samples/scala-fibonacci-action/build.sbt

@@ -2,26 +2,24 @@ name := "fibonacci-action"
 
 organization := "com.akkaserverless.samples"
 organizationHomepage := Some(url("https://akkaserverless.com"))
-licenses := Seq(
-  ("CC0", url("https://creativecommons.org/publicdomain/zero/1.0"))
-)
+licenses := Seq(("CC0", url("https://creativecommons.org/publicdomain/zero/1.0")))
 
 scalaVersion := "2.13.6"
 
-enablePlugins(AkkaserverlessPlugin)
+enablePlugins(AkkaserverlessPlugin, JavaAppPackaging, DockerPlugin)
+dockerBaseImage := "docker.io/library/adoptopenjdk:11-jre-hotspot"
+dockerUsername := sys.props.get("docker.username")
+dockerRepository := sys.props.get("docker.registry")
+ThisBuild / dynverSeparator := "-"
 
 Compile / scalacOptions ++= Seq(
   "-target:11",
   "-deprecation",
   "-feature",
   "-unchecked",
   "-Xlog-reflective-calls",
-  "-Xlint"
-)
-Compile / javacOptions ++= Seq(
-  "-Xlint:unchecked",
-  "-Xlint:deprecation",
-  "-parameters" // for Jackson
+  "-Xlint")
+Compile / javacOptions ++= Seq("-Xlint:unchecked", "-Xlint:deprecation", "-parameters" // for Jackson
 )
 
 Test / parallelExecution := false

samples/scala-fibonacci-action/project/plugins.sbt

@@ -1 +1,4 @@
 addSbtPlugin("com.akkaserverless" % "sbt-akkaserverless" % System.getProperty("akkaserverless-sdk.version", "0.7.2"))
+addSbtPlugin("com.typesafe.sbt" % "sbt-native-packager" % "1.8.1")
+addSbtPlugin("com.dwijnand" % "sbt-dynver" % "4.1.1")
+addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.4.2")

samples/scala-fibonacci-action/src/main/scala/com/example/fibonacci/FibonacciAction.scala

@@ -0,0 +1,34 @@
+/* This code was generated by Akka Serverless tooling.
+ * As long as this file exists it will not be re-generated.
+ * You are free to make changes to this file.
+ */
+package com.example.fibonacci
+
+import com.akkaserverless.scalasdk.action.Action
+import com.akkaserverless.scalasdk.action.ActionCreationContext
+
+/** An action. */
+class FibonacciAction(creationContext: ActionCreationContext) extends AbstractFibonacciAction {
+
+  private def isFibonacci(num: Long): Boolean = {
+    val isPerfectSquare = (n: Long) => {
+      val square = Math.sqrt(n.toDouble).toLong
+      square * square == n
+    }
+    isPerfectSquare(5 * num * num + 4) || isPerfectSquare(5 * num * num - 4)
+  }
+
+  private def nextFib(num: Long): Long = {
+    val result = num * (1 + Math.sqrt(5)) / 2.0;
+    Math.round(result)
+  }
+
+  /** Handler for "NextNumber". */
+  override def nextNumber(number: Number): Action.Effect[Number] = {
+    val num = number.value
+    if (isFibonacci(num))
+      effects.reply(Number(nextFib(num)))
+    else
+      effects.error(s"Input number is not a Fibonacci number, received '$num'")
+  }
+}

samples/scala-fibonacci-action/src/main/scala/com/example/fibonacci/Main.scala

@@ -0,0 +1,23 @@
+package com.example.fibonacci
+
+import com.akkaserverless.scalasdk.AkkaServerless
+import org.slf4j.LoggerFactory
+
+object Main {
+
+  private val log = LoggerFactory.getLogger("com.example.fibonacci.Main")
+
+  def createAkkaServerless(): AkkaServerless = {
+    // The AkkaServerlessFactory automatically registers any generated Actions, Views or Entities,
+    // and is kept up-to-date with any changes in your protobuf definitions.
+    // If you prefer, you may remove this and manually register these components in a
+    // `AkkaServerless()` instance.
+    AkkaServerlessFactory.withComponents(
+      new FibonacciAction(_))
+  }
+
+  def main(args: Array[String]): Unit = {
+    log.info("starting the Akka Serverless service")
+    createAkkaServerless().start()
+  }
+}