+doc #19429 initial merge of docs-dev and docs

akka-docs/rst/scala/code/docs/stream/ActorPublisherDocSpec.scala

@@ -0,0 +1,96 @@
+/**
+ * Copyright (C) 2014 Typesafe Inc. <http://www.typesafe.com>
+ */
+package docs.stream
+
+import scala.annotation.tailrec
+import akka.actor.Props
+import akka.stream.ActorMaterializer
+import akka.stream.actor.ActorPublisher
+import akka.stream.scaladsl.{ Flow, Sink, Source }
+import akka.stream.testkit.AkkaSpec
+
+object ActorPublisherDocSpec {
+
+  //#job-manager
+  object JobManager {
+    def props: Props = Props[JobManager]
+
+    final case class Job(payload: String)
+    case object JobAccepted
+    case object JobDenied
+  }
+
+  class JobManager extends ActorPublisher[JobManager.Job] {
+    import akka.stream.actor.ActorPublisherMessage._
+    import JobManager._
+
+    val MaxBufferSize = 100
+    var buf = Vector.empty[Job]
+
+    def receive = {
+      case job: Job if buf.size == MaxBufferSize =>
+        sender() ! JobDenied
+      case job: Job =>
+        sender() ! JobAccepted
+        if (buf.isEmpty && totalDemand > 0)
+          onNext(job)
+        else {
+          buf :+= job
+          deliverBuf()
+        }
+      case Request(_) =>
+        deliverBuf()
+      case Cancel =>
+        context.stop(self)
+    }
+
+    @tailrec final def deliverBuf(): Unit =
+      if (totalDemand > 0) {
+        /*
+         * totalDemand is a Long and could be larger than
+         * what buf.splitAt can accept
+         */
+        if (totalDemand <= Int.MaxValue) {
+          val (use, keep) = buf.splitAt(totalDemand.toInt)
+          buf = keep
+          use foreach onNext
+        } else {
+          val (use, keep) = buf.splitAt(Int.MaxValue)
+          buf = keep
+          use foreach onNext
+          deliverBuf()
+        }
+      }
+  }
+  //#job-manager
+}
+
+class ActorPublisherDocSpec extends AkkaSpec {
+  import ActorPublisherDocSpec._
+
+  implicit val materializer = ActorMaterializer()
+
+  "illustrate usage of ActorPublisher" in {
+    def println(s: String): Unit =
+      testActor ! s
+
+    //#actor-publisher-usage
+    val jobManagerSource = Source.actorPublisher[JobManager.Job](JobManager.props)
+    val ref = Flow[JobManager.Job]
+      .map(_.payload.toUpperCase)
+      .map { elem => println(elem); elem }
+      .to(Sink.ignore)
+      .runWith(jobManagerSource)
+
+    ref ! JobManager.Job("a")
+    ref ! JobManager.Job("b")
+    ref ! JobManager.Job("c")
+    //#actor-publisher-usage
+
+    expectMsg("A")
+    expectMsg("B")
+    expectMsg("C")
+  }
+
+}