+doc #15239: Stream cookbook

akka-docs-dev/rst/scala/code/docs/stream/cookbook/RecipeManualTrigger.scala

@@ -0,0 +1,94 @@
+package docs.stream.cookbook
+
+import akka.stream.scaladsl._
+import akka.stream.testkit.StreamTestKit
+import akka.stream.testkit.StreamTestKit.{ SubscriberProbe, PublisherProbe }
+import scala.concurrent.duration._
+
+class RecipeManualTrigger extends RecipeSpec {
+
+  "Recipe for triggering a stream manually" must {
+
+    "work" in {
+
+      val elements = Source(List("1", "2", "3", "4"))
+      val pub = PublisherProbe[Trigger]()
+      val sub = SubscriberProbe[Message]()
+      val triggerSource = Source(pub)
+      val sink = Sink(sub)
+
+      //#manually-triggered-stream
+      import FlowGraphImplicits._
+      val graph = FlowGraph { implicit builder =>
+        val zip = Zip[Message, Trigger]
+        elements ~> zip.left
+        triggerSource ~> zip.right
+        zip.out ~> Flow[(Message, Trigger)].map { case (msg, trigger) => msg } ~> sink
+      }
+      //#manually-triggered-stream
+
+      graph.run()
+      val manualSource = new StreamTestKit.AutoPublisher(pub)
+
+      sub.expectSubscription().request(1000)
+      sub.expectNoMsg(100.millis)
+
+      manualSource.sendNext(())
+      sub.expectNext("1")
+      sub.expectNoMsg(100.millis)
+
+      manualSource.sendNext(())
+      manualSource.sendNext(())
+      sub.expectNext("2")
+      sub.expectNext("3")
+      sub.expectNoMsg(100.millis)
+
+      manualSource.sendNext(())
+      sub.expectNext("4")
+      sub.expectComplete()
+    }
+
+    "work with ZipWith" in {
+
+      val elements = Source(List("1", "2", "3", "4"))
+      val pub = PublisherProbe[Trigger]()
+      val sub = SubscriberProbe[Message]()
+      val triggerSource = Source(pub)
+      val sink = Sink(sub)
+
+      //#manually-triggered-stream-zipwith
+      import FlowGraphImplicits._
+      val graph = FlowGraph { implicit builder =>
+        val zip = ZipWith[Message, Trigger, Message](
+          (msg: Message, trigger: Trigger) => msg)
+
+        elements ~> zip.left
+        triggerSource ~> zip.right
+        zip.out ~> sink
+      }
+      //#manually-triggered-stream-zipwith
+
+      graph.run()
+      val manualSource = new StreamTestKit.AutoPublisher(pub)
+
+      sub.expectSubscription().request(1000)
+      sub.expectNoMsg(100.millis)
+
+      manualSource.sendNext(())
+      sub.expectNext("1")
+      sub.expectNoMsg(100.millis)
+
+      manualSource.sendNext(())
+      manualSource.sendNext(())
+      sub.expectNext("2")
+      sub.expectNext("3")
+      sub.expectNoMsg(100.millis)
+
+      manualSource.sendNext(())
+      sub.expectNext("4")
+      sub.expectComplete()
+    }
+
+  }
+
+}