ActorSource.actorRef

Materialize an ActorRef<T>ActorRef[T] of the new actors API; sending messages to it will emit them on the stream only if they are of the same type as the stream.

Actor interop operators

Dependency

The Akka dependencies are available from Akka’s library repository. To access them there, you need to configure the URL for this repository.

sbt

resolvers += "Akka library repository".at("https://repo.akka.io/maven")

Maven

<project>
  ...
  <repositories>
    <repository>
      <id>akka-repository</id>
      <name>Akka library repository</name>
      <url>https://repo.akka.io/maven</url>
    </repository>
  </repositories>
</project>

Gradle

repositories {
    mavenCentral()
    maven {
        url "https://repo.akka.io/maven"
    }
}

This operator is included in:

sbt

val AkkaVersion = "2.9.1"
libraryDependencies += "com.typesafe.akka" %% "akka-stream-typed" % AkkaVersion

Maven

<properties>
  <scala.binary.version>2.13</scala.binary.version>
</properties>
<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>com.typesafe.akka</groupId>
      <artifactId>akka-bom_${scala.binary.version}</artifactId>
      <version>2.9.1</version>
      <type>pom</type>
      <scope>import</scope>
    </dependency>
  </dependencies>
</dependencyManagement>
<dependencies>
  <dependency>
    <groupId>com.typesafe.akka</groupId>
    <artifactId>akka-stream-typed_${scala.binary.version}</artifactId>
  </dependency>
</dependencies>

Gradle

def versions = [
  ScalaBinary: "2.13"
]
dependencies {
  implementation platform("com.typesafe.akka:akka-bom_${versions.ScalaBinary}:2.9.1")

  implementation "com.typesafe.akka:akka-stream-typed_${versions.ScalaBinary}"
}

Signature

ActorSource.actorRefActorSource.actorRef

Description

Materialize an ActorRef<T>ActorRef[T] which only accepts messages that are of the same type as the stream.

See also:

• ActorSource.actorRefWithBackpressure This operator, but with backpressure control
• Source.actorRef The corresponding operator for the classic actors API
• Source.actorRefWithBackpressure The operator for the classic actors API with backpressure control
• Source.queue Materialize a SourceQueue onto which elements can be pushed for emitting from the source

Examples

Scala

copysourceimport akka.actor.typed.ActorRef
import akka.stream.OverflowStrategy
import akka.stream.scaladsl.{ Sink, Source }
import akka.stream.typed.scaladsl.ActorSource

trait Protocol
case class Message(msg: String) extends Protocol
case object Complete extends Protocol
case class Fail(ex: Exception) extends Protocol

val source: Source[Protocol, ActorRef[Protocol]] = ActorSource.actorRef[Protocol](completionMatcher = {
  case Complete =>
}, failureMatcher = {
  case Fail(ex) => ex
}, bufferSize = 8, overflowStrategy = OverflowStrategy.fail)

val ref = source
  .collect {
    case Message(msg) => msg
  }
  .to(Sink.foreach(println))
  .run()

ref ! Message("msg1")
// ref ! "msg2" Does not compile

Java

copysourceimport akka.actor.typed.ActorRef;
import akka.actor.typed.ActorSystem;
import akka.japi.JavaPartialFunction;
import akka.stream.OverflowStrategy;
import akka.stream.javadsl.Sink;
import akka.stream.javadsl.Source;
import akka.stream.typed.javadsl.ActorSource;
import java.util.Optional;


interface Protocol {}

class Message implements Protocol {
  private final String msg;

  public Message(String msg) {
    this.msg = msg;
  }
}

class Complete implements Protocol {}

class Fail implements Protocol {
  private final Exception ex;

  public Fail(Exception ex) {
    this.ex = ex;
  }
}

  final Source<Protocol, ActorRef<Protocol>> source =
      ActorSource.actorRef(
          (m) -> m instanceof Complete,
          (m) -> (m instanceof Fail) ? Optional.of(((Fail) m).ex) : Optional.empty(),
          8,
          OverflowStrategy.fail());

  final ActorRef<Protocol> ref =
      source
          .collect(
              new JavaPartialFunction<Protocol, String>() {
                public String apply(Protocol p, boolean isCheck) {
                  if (p instanceof Message) {
                    return ((Message) p).msg;
                  } else {
                    throw noMatch();
                  }
                }
              })
          .to(Sink.foreach(System.out::println))
          .run(system);

  ref.tell(new Message("msg1"));
  // ref.tell("msg2"); Does not compile