Add wiretap/wiretapContext to FlowWithContext/SourceWithContext

docs/src/main/paradox/release-notes/releases-1.1.md

@@ -5,6 +5,11 @@
 Release notes for Apache Pekko 1.1.0-M1. See [GitHub Milestone](https://github.com/apache/pekko/milestone/2?closed=1) for fuller list of changes.
 As with all milestone releases, this release is not recommended for production use - it is designed to allow users to try out the changes in a test environment.
 
+### Additional APIs
+* add optionalVia/unsafeOptionalDataVia operators ([PR1422](https://github.com/apache/pekko/pull/1422))
+* add alsoTo/alsoToContext operators to `SourceWithContext`/`FlowWithContext` ([PR-1443](https://github.com/apache/pekko/pull/1443))
+* add wireTap/wireTapContext operators to `SourceWithContext`/`FlowWithContext` ([PR-1446](https://github.com/apache/pekko/pull/1446))
+
 ### 1.0.x changes
 
 Apache Pekko 1.1.0-M1 contains all of the changes that have been released in the @ref:[1.0.x releases](releases-1.0.md) up to and including v1.0.3-M1.
@@ -41,8 +46,6 @@ The Stream API has been updated to add some extra functions.
 * add Sink.forall operator ([PR989](https://github.com/apache/pekko/pull/989))
 * add Source.iterate operator ([PR1244](https://github.com/apache/pekko/pull/1244))
 * added extra retry operators that allow users to provide a predicate to decide whether to retry based on the exception ([PR1269](https://github.com/apache/pekko/pull/1269))
-* add optionalVia/unsafeOptionalDataVia operators ([PR1422](https://github.com/apache/pekko/pull/1422))
-* add alsoTo/alsoToContext operators to `SourceWithContext`/`FlowWithContext` ([PR-1443](https://github.com/apache/pekko/pull/1443))
 
 The Stream Testkit Java DSL has some extra functions.
 

stream-tests/src/test/scala/org/apache/pekko/stream/scaladsl/FlowWithContextSpec.scala

@@ -126,6 +126,50 @@ class FlowWithContextSpec extends StreamSpec {
  }
  }
 
+ "pass through all data when using wireTap" in {
+ val listBuffer = new ListBuffer[String]()
+ Source(Vector(Message("A", 1L), Message("B", 2L), Message("D", 3L), Message("C", 4L)))
+ .asSourceWithContext(_.offset)
+ .via(
+ FlowWithContext.fromTuples(Flow.fromFunction[(Message, Long), (String, Long)] { case (data, offset) =>
+ (data.data.toLowerCase, offset)
+ }).wireTap(Sink.foreach(string => listBuffer.+=(string)))
+ )
+ .toMat(TestSink.probe[(String, Long)])(Keep.right)
+ .run()
+ .request(4)
+ .expectNext(("a", 1L))
+ .expectNext(("b", 2L))
+ .expectNext(("d", 3L))
+ .expectNext(("c", 4L))
+ .expectComplete()
+ .within(10.seconds) {
+ listBuffer should contain atLeastOneElementOf List("a", "b", "d", "c")
+ }
+ }
+
+ "pass through all data when using wireTapContext" in {
+ val listBuffer = new ListBuffer[Long]()
+ Source(Vector(Message("A", 1L), Message("B", 2L), Message("D", 3L), Message("C", 4L)))
+ .asSourceWithContext(_.offset)
+ .via(
+ FlowWithContext.fromTuples(Flow.fromFunction[(Message, Long), (String, Long)] { case (data, offset) =>
+ (data.data.toLowerCase, offset)
+ }).wireTapContext(Sink.foreach(offset => listBuffer.+=(offset)))
+ )
+ .toMat(TestSink.probe[(String, Long)])(Keep.right)
+ .run()
+ .request(4)
+ .expectNext(("a", 1L))
+ .expectNext(("b", 2L))
+ .expectNext(("d", 3L))
+ .expectNext(("c", 4L))
+ .expectComplete()
+ .within(10.seconds) {
+ listBuffer should contain atLeastOneElementOf List(1L, 2L, 3L, 4L)
+ }
+ }
+
  "keep the same order for data and context when using unsafeDataVia" in {
  val data = List(("1", 1), ("2", 2), ("3", 3), ("4", 4))
 

stream-tests/src/test/scala/org/apache/pekko/stream/scaladsl/SourceWithContextSpec.scala

@@ -115,6 +115,44 @@ class SourceWithContextSpec extends StreamSpec {
  }
  }
 
+ "pass through all data when using wireTap" in {
+ val listBuffer = new ListBuffer[Message]()
+ val messages = Vector(Message("A", 1L), Message("B", 2L), Message("D", 3L), Message("C", 4L))
+ Source(messages)
+ .asSourceWithContext(_.offset)
+ .wireTap(Sink.foreach(message => listBuffer.+=(message)))
+ .toMat(TestSink.probe[(Message, Long)])(Keep.right)
+ .run()
+ .request(4)
+ .expectNext((Message("A", 1L), 1L))
+ .expectNext((Message("B", 2L), 2L))
+ .expectNext((Message("D", 3L), 3L))
+ .expectNext((Message("C", 4L), 4L))
+ .expectComplete()
+ .within(10.seconds) {
+ listBuffer.toVector should contain atLeastOneElementOf messages
+ }
+ }
+
+ "pass through all data when using wireTapContext" in {
+ val listBuffer = new ListBuffer[Long]()
+ val messages = Vector(Message("A", 1L), Message("B", 2L), Message("D", 3L), Message("C", 4L))
+ Source(messages)
+ .asSourceWithContext(_.offset)
+ .wireTapContext(Sink.foreach(offset => listBuffer.+=(offset)))
+ .toMat(TestSink.probe[(Message, Long)])(Keep.right)
+ .run()
+ .request(4)
+ .expectNext((Message("A", 1L), 1L))
+ .expectNext((Message("B", 2L), 2L))
+ .expectNext((Message("D", 3L), 3L))
+ .expectNext((Message("C", 4L), 4L))
+ .expectComplete()
+ .within(10.seconds) {
+ listBuffer.toVector should contain atLeastOneElementOf (messages.map(_.offset))
+ }
+ }
+
  "pass through contexts via a FlowWithContext" in {
 
  def flowWithContext[T] = FlowWithContext[T, Long]

stream/src/main/mima-filters/1.0.x.backwards.excludes/pr-1446-wireTap-wireTapContext-source-flow-with-context.backwards.excludes

@@ -0,0 +1,2 @@
+ ProblemFilters.exclude[ReversedMissingMethodProblem]("org.apache.pekko.stream.scaladsl.FlowWithContextOps.wireTap")
+ ProblemFilters.exclude[ReversedMissingMethodProblem]("org.apache.pekko.stream.scaladsl.FlowWithContextOps.wireTapContext")

stream/src/main/scala/org/apache/pekko/stream/scaladsl/FlowWithContext.scala

@@ -144,6 +144,12 @@ final class FlowWithContext[-In, -CtxIn, +Out, +CtxOut, +Mat](delegate: Flow[(In
  override def alsoToContext(that: Graph[SinkShape[CtxOut], _]): Repr[Out, CtxOut] =
  FlowWithContext.fromTuples(delegate.alsoTo(Sink.contramapImpl(that, (in: (Out, CtxOut)) => in._2)))
 
+ override def wireTap(that: Graph[SinkShape[Out], _]): Repr[Out, CtxOut] =
+ FlowWithContext.fromTuples(delegate.wireTap(Sink.contramapImpl(that, (in: (Out, CtxOut)) => in._1)))
+
+ override def wireTapContext(that: Graph[SinkShape[CtxOut], _]): Repr[Out, CtxOut] =
+ FlowWithContext.fromTuples(delegate.wireTap(Sink.contramapImpl(that, (in: (Out, CtxOut)) => in._2)))
+
  /**
  * Context-preserving variant of [[pekko.stream.scaladsl.Flow.withAttributes]].
  *

stream/src/main/scala/org/apache/pekko/stream/scaladsl/FlowWithContextOps.scala

@@ -104,6 +104,22 @@ trait FlowWithContextOps[+Out, +Ctx, +Mat] {
  */
  def alsoToContext(that: Graph[SinkShape[Ctx], _]): Repr[Out, Ctx]
 
+ /**
+ * Data variant of [[pekko.stream.scaladsl.FlowOps.wireTap]]
+ *
+ * @see [[pekko.stream.scaladsl.FlowOps.wireTap]]
+ * @since 1.1.0
+ */
+ def wireTap(that: Graph[SinkShape[Out], _]): Repr[Out, Ctx]
+
+ /**
+ * Context variant of [[pekko.stream.scaladsl.FlowOps.wireTap]]
+ *
+ * @see [[pekko.stream.scaladsl.FlowOps.wireTap]]
+ * @since 1.1.0
+ */
+ def wireTapContext(that: Graph[SinkShape[Ctx], _]): Repr[Out, Ctx]
+
  /**
  * Context-preserving variant of [[pekko.stream.scaladsl.FlowOps.map]].
  *

stream/src/main/scala/org/apache/pekko/stream/scaladsl/SourceWithContext.scala

@@ -161,6 +161,12 @@ final class SourceWithContext[+Out, +Ctx, +Mat] private[stream] (delegate: Sourc
  override def alsoToContext(that: Graph[SinkShape[Ctx], _]): Repr[Out, Ctx] =
  SourceWithContext.fromTuples(delegate.alsoTo(Sink.contramapImpl(that, (in: (Out, Ctx)) => in._2)))
 
+ override def wireTap(that: Graph[SinkShape[Out], _]): Repr[Out, Ctx] =
+ SourceWithContext.fromTuples(delegate.wireTap(Sink.contramapImpl(that, (in: (Out, Ctx)) => in._1)))
+
+ override def wireTapContext(that: Graph[SinkShape[Ctx], _]): Repr[Out, Ctx] =
+ SourceWithContext.fromTuples(delegate.wireTap(Sink.contramapImpl(that, (in: (Out, Ctx)) => in._2)))
+
  /**
  * Connect this [[pekko.stream.scaladsl.SourceWithContext]] to a [[pekko.stream.scaladsl.Sink]] and run it.
  * The returned value is the materialized value of the `Sink`.