How to use Logging into Akka actor? - scala

Question

Can I set Logging in Akka actor by implicit? I would like to log inside the actor. My code is as given below:
object EmployeeRouterActor {
final case class Employee(id: Long, name: String)
final case object StopChild
final case class ChildResponse(id: Long, name: String)
}
final class EmployeeRouterActor extends Actor with akka.actor.ActorLogging {
import EmployeeRouterActor._
private var children = Map.empty[Long, ActorRef]
override def receive: Receive = {
case e # Employee(id, _) => {
getChild(id) ! e
}
case r # ChildResponse(id, _) => {
stopChild(id)
val idItem = r.id
val nameItem = r.name
sender ! s"Employee {$idItem} is $nameItem."
}
}
private def getChild(id: Long): ActorRef =
context.child(id.toString).getOrElse {
val child = context.actorOf(EmployeeEchoActor.apply(), id.toString)
children += (id -> child)
child
}
private def stopChild(id: Long) = {
children(id) ! StopChild
children -= id
}
}
But, in this case, I can not do something like this:
class EmployeeRouterActor (implicit logger: LoggingAdapter) { ... }
I have got following errors:
Error:(10, 30) could not find implicit value for parameter logger: akka.event.LoggingAdapter
def apply(): Props = Props(new EmployeeEchoActor)
Error:(10, 30) not enough arguments for constructor EmployeeEchoActor: (implicit logger: akka.event.LoggingAdapter)actors.EmployeeEchoActor.
Unspecified value parameter logger.
def apply(): Props = Props(new EmployeeEchoActor)
Is it possible to use Logging from Akka inside the actors?
EmployeeEchoActor (child actor) is defined as given below:
object EmployeeEchoActor {
def apply(): Props = Props(new EmployeeEchoActor)
}
class EmployeeEchoActor(implicit logger: LoggingAdapter) extends Actor {
override def receive = {
case employee: EmployeeRouterActor.Employee => {
logger.info("Message received!")
val idItem = employee.id
val nameItem = employee.name
context.parent ! EmployeeRouterActor.ChildResponse( idItem, nameItem )
}
case EmployeeRouterActor.StopChild => {
logger.info("Stopping :(!")
context.stop(self)
}
case _ => sender ! "Internal Error!"
}
}

Answer 1

The solution is:
final class EmployeeRouterActor extends Actor with akka.actor.ActorLogging {
Implement ActorLogging and use log at code, for example:
override def receive: Receive = {
case e # Employee(id, _) => {
log.info("Message received!")
getChild(id) ! e
}
case r # ChildResponse(id, _) => {
log.info("Response received from child!")
stopChild(id)
log.info("Child has been stopped!")
val idItem = r.id
val nameItem = r.name
sender ! s"Employee {$idItem} is $nameItem."
}
}