akka.persistence.multidc.internal

Class NotificationReader

java.lang.Object

akka.persistence.multidc.internal.NotificationReader

All Implemented Interfaces:

akka.actor.Actor, akka.actor.ActorLogging, akka.actor.Timers

public class NotificationReader
extends java.lang.Object
implements akka.actor.Actor, akka.actor.ActorLogging, akka.actor.Timers

INTERNAL API

Reads rows from the notification table and publish those to interested subscribers, with an optional delay defined by publishDelay and additionalRandomPublishDelay.

The notification table is structured in time buckets (e.g. 1 minute periods) to allow for efficient removal of old entries.

It starts at the given startTimestamp. It performs the queries periodically with the readInterval. It keeps track of latest timestamp for the latest (current) bucket and uses that in the query to only select newer. When no more events are found in current time bucket it progress to next bucket (but not ahead of current time).

Replication of rows can be delayed and to find such delayed rows in current bucket and old buckets it also performs so called backtracking queries. A backtracking query scans all rows in a time bucket to find rows that have not been published previously. It looks back for maxBacktrackingBuckets but scans only one bucket per tick. It switches between backtracking queries and queries of latest rows in current bucket. There is only one query in progress at a time.

Nested Class Summary

Nested classes/interfaces inherited from interface akka.actor.Actor

akka.actor.Actor.emptyBehavior$, akka.actor.Actor.ignoringBehavior$

Constructor Summary

Constructors

Constructor and Description
NotificationReader(long startTimestamp, NotificationSettings settings, akka.persistence.cassandra.session.scaladsl.CassandraSession session, java.lang.String readNotificationCql, scala.Function2<java.lang.String,NotificationWriter.EventsWritten,scala.runtime.BoxedUnit> notificationCallback)

Method Summary

Modifier and Type	Method and Description
protected void	akka$actor$Actor$_setter_$context_$eq(akka.actor.ActorContext x$1)
protected void	akka$actor$Actor$_setter_$self_$eq(akka.actor.ActorRef x$1)
akka.actor.ActorContext	context()
scala.PartialFunction<java.lang.Object,scala.runtime.BoxedUnit>	idle()
akka.event.LoggingAdapter	log()
static akka.actor.Props	props(long startTimestamp, NotificationSettings notificationConfig, akka.persistence.cassandra.session.scaladsl.CassandraSession session, java.lang.String readNotificationCql, scala.Function2<java.lang.String,NotificationWriter.EventsWritten,scala.runtime.BoxedUnit> notificationCallback)
scala.PartialFunction<java.lang.Object,scala.runtime.BoxedUnit>	receive()
akka.actor.ActorRef	self()

Methods inherited from class java.lang.Object

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

Methods inherited from interface akka.actor.ActorLogging

$init$, akka$actor$ActorLogging$$_log_$eq, akka$actor$ActorLogging$$_log

Methods inherited from interface akka.actor.Timers

$init$, akka$actor$Timers$_setter_$akka$actor$Timers$$_timers_$eq, akka$actor$Timers$$_timers, aroundPostStop, aroundPreRestart, aroundReceive, timers

Methods inherited from interface akka.actor.Actor

$init$, aroundPostRestart, aroundPreStart, noSender, postRestart, postStop, preRestart, preStart, sender, supervisorStrategy, unhandled

Constructor Detail

NotificationReader

public NotificationReader(long startTimestamp,
                          NotificationSettings settings,
                          akka.persistence.cassandra.session.scaladsl.CassandraSession session,
                          java.lang.String readNotificationCql,
                          scala.Function2<java.lang.String,NotificationWriter.EventsWritten,scala.runtime.BoxedUnit> notificationCallback)

Method Detail

props

public static akka.actor.Props props(long startTimestamp,
                                     NotificationSettings notificationConfig,
                                     akka.persistence.cassandra.session.scaladsl.CassandraSession session,
                                     java.lang.String readNotificationCql,
                                     scala.Function2<java.lang.String,NotificationWriter.EventsWritten,scala.runtime.BoxedUnit> notificationCallback)

context

public akka.actor.ActorContext context()

Specified by:

context in interface akka.actor.Actor

self

public final akka.actor.ActorRef self()

Specified by:

self in interface akka.actor.Actor

akka$actor$Actor$_setter_$context_$eq

protected void akka$actor$Actor$_setter_$context_$eq(akka.actor.ActorContext x$1)

Specified by:

akka$actor$Actor$_setter_$context_$eq in interface akka.actor.Actor

akka$actor$Actor$_setter_$self_$eq

protected final void akka$actor$Actor$_setter_$self_$eq(akka.actor.ActorRef x$1)

Specified by:

akka$actor$Actor$_setter_$self_$eq in interface akka.actor.Actor

log

public akka.event.LoggingAdapter log()

Specified by:

log in interface akka.actor.ActorLogging

receive

public scala.PartialFunction<java.lang.Object,scala.runtime.BoxedUnit> receive()

Specified by:

receive in interface akka.actor.Actor

idle

public scala.PartialFunction<java.lang.Object,scala.runtime.BoxedUnit> idle()