Package org.apache.pekko.cluster.sharding.typed

Class ShardingDirectReplication

java.lang.Object

org.apache.pekko.cluster.sharding.typed.ShardingDirectReplication

public class ShardingDirectReplication
extends Object

INTERNAL API

Used when sharding Replicated Event Sourced entities in multiple instances of sharding, for example one per DC in a Multi DC Pekko Cluster.

This actor should be started once on each node where Replicated Event Sourced entities will run (the same nodes that you start sharding on). The entities should be set up with pekko.persistence.typed.scaladsl.EventSourcedBehavior.withEventPublishing or pekko.persistence.typed.javadsl.ReplicatedEventSourcedBehavior#withEventPublishing() If using ReplicatedSharding the replication can be enabled through ReplicatedEntityProvider.withDirectReplication instead of starting this actor manually.

Subscribes to locally written events through the event stream and sends the seen events to all the sharded replicas which can then fast forward their cross-replica event streams to improve latency while allowing less frequent poll for the cross replica queries. Note that since message delivery is at-most-once this can not be the only channel for replica events - the entities must still tail events from the journals of other replicas.

The events are forwarded as pekko.cluster.sharding.typed.ShardingEnvelope this will work out of the box both by default and with a custom extractor since the envelopes are handled internally.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ShardingDirectReplication.Command	Not for user extension
static class	ShardingDirectReplication.VerifyStarted$

Constructor Summary

Constructors

Constructor	Description
ShardingDirectReplication()

Method Summary

Modifier and Type	Method	Description
static <T> Behavior<ShardingDirectReplication.Command>	apply(String typeName, scala.Option<ReplicaId> selfReplica, scala.collection.immutable.Map<ReplicaId,ActorRef<T>> replicaShardingProxies)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ShardingDirectReplication

public ShardingDirectReplication()

Method Details

apply

public static <T>
Behavior<ShardingDirectReplication.Command> apply(String typeName,
 scala.Option<ReplicaId> selfReplica,
 scala.collection.immutable.Map<ReplicaId,ActorRef<T>> replicaShardingProxies)