Add LogWithMarker to Akka Stream #28450

akka-docs/src/test/java/jdocs/stream/operators/SourceOrFlow.java

@@ -35,12 +35,14 @@ import java.util.Arrays;
 // #zip
 
 // #log
+import akka.event.LogMarker;
 import akka.stream.Attributes;
 
 // #log
 
 import java.time.Duration;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CompletionStage;
@@ -61,6 +63,20 @@ class SourceOrFlow {
     ;
   }
 
+  void logWithMarkerExample() {
+    Flow.of(String.class)
+        // #logWithMarker
+        .logWithMarker(
+            "myStream", (e) -> LogMarker.create("myMarker", Collections.singletonMap("element", e)))
+        .addAttributes(
+            Attributes.createLogLevels(
+                Attributes.logLevelOff(), // onElement
+                Attributes.logLevelInfo(), // onFinish
+                Attributes.logLevelError())) // onFailure
+    // #logWithMarker
+    ;
+  }
+
   void zipWithIndexExample() {
     // #zip-with-index
     Source.from(Arrays.asList("apple", "orange", "banana"))

akka-docs/src/test/scala/docs/stream/operators/sourceorflow/LogWithMarker.scala

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2019-2020 Lightbend Inc. <https://www.lightbend.com>
+ */
+
+package docs.stream.operators.sourceorflow
+
+import akka.stream.scaladsl.Flow
+//#logWithMarker
+import akka.event.LogMarker
+import akka.stream.Attributes
+
+//#logWithMarker
+
+object LogWithMarker {
+  def logWithMarkerExample(): Unit = {
+    Flow[String]
+    //#logWithMarker
+      .logWithMarker(name = "myStream", e => LogMarker(name = "myMarker", properties = Map("element" -> e)))
+      .addAttributes(
+        Attributes.logLevels(
+          onElement = Attributes.LogLevels.Off,
+          onFinish = Attributes.LogLevels.Info,
+          onFailure = Attributes.LogLevels.Error))
+    //#logWithMarker
+  }
+}