Hi Mark, there are some ways to achieve what you want, but propagating the exception in the same thread is not directly achievable with any async framework,
One way - asking: Use Actors and `?` (ask) your backend for a response. The actor will complete the future or it will contain a timeout. Or you could reply to the future by sending it an exception.. Sometimes this method is good enough, though not the most performant one. Another way - per-request actor pattern: Though this is spray / akka-http specific, as you can _.complete(data) a request asynchronously. Used by our friends at net-a-porter and described in detail in this blog post: http://techblog.net-a-porter.com/2013/12/ask-tell-and-per-request-actors/ I hope this helps, even if only to inspire for another solution! -- konrad On Wed, Oct 15, 2014 at 3:47 PM, Mark Kaberman <mkaber...@gmail.com> wrote: > Rafal, > > Thanks for the clarification. The pattern you are describing works very > well if your entire application is Akka based. In that case there is no > need to externalize the exceptions, everything is handled internally. Rest > controllers are a different matter. My thought was that different > controllers will spawn different actor hierarchies, some simple (as in > example above where a single actor is responsible for handing the > persistence) some very complicated with the deep actor's tree. I wanted to > be able to handle actor's exception's in simple cases, but now I realize > that Akk won't let me do it. I guess I will have to rethink my strategy. > > Thanks, > > Mark > > > On Tuesday, October 14, 2014 5:25:29 PM UTC-4, Rafał Krzewski wrote: >> >> This is not how things work in Akka-land :) Exceptions thrown in an >> Actors receive method are reported to it's supervisor actor which may >> choose to escalate it (among other choices), but that means that the >> supervisor itself terminates abnormally throwing an exception that is >> passed in turn to it's own supervisor. Its no wonder that the Guardian >> actor refuses to escalate the exception, because it would make your whole >> ActorSystem inoperable. >> >> I can see two paths from here: you could follow the error kernel pattern >> and use intermediate actor: Let your Spring controller create a "safe" >> actor, that will spawn a child actor to do the "dangerous" work and handle >> the child's failure appropriately. The second choice is not letting the >> exception to escape receive method: catch it and send a message that >> describes the error to the Spring controller. >> >> Hope that helps, >> Rafał >> >> W dniu wtorek, 14 października 2014 22:03:19 UTC+2 użytkownik Mark >> Kaberman napisał: >>> >>> I have Spring MVC controller class in my application which creates top >>> level Akka actor (via Spring). When this actor throws an exception I expect >>> it to be handled by the controller, but in my case the actor simply times >>> out after 5 sec. I tried to implement my own SupervisorStrategyConfigurator >>> which I put into my Akka configuration file like this: >>> akka.actor.guardian-supervisor-strategy = "com....akka. >>> GuardianActorSupervisorStrategyConfigurator" >>> but it does not seem to have any effect >>> >>> This is the way I instantiate Akka in my rest controller: >>> public class MyRestController { >>> >>> @Autowired >>> private ActorSystem system; >>> >>> @Autowired >>> private AkkaSpringExtension extention; >>> >>> private ActorRef persistenceActor; >>> >>> @PostConstruct >>> public void init() { >>> try { >>> persistenceActor = system.actorOf(extention. >>> props("persistenceActor").withRouter( new FromConfig()), >>> "persistenceActor"); >>> } catch (Throwable e) { >>> ... >>> } >>> } >>> >>> .... >>> } >>> >>> inside controller's method I call persistenceActor.tell(message, null); >>> >>> When my actor throws an exception the controller gets >>> AkkaTimeoutException instead of the exception thrown by the actor. >>> >>> I am wondering how can I force my actor to escalate the exception to the >>> rest controller? Putting escalate() into my >>> GuardianActorSupervisorStrategyConfigurator >>> does not seem to be working >>> >>> Thanks, >>> >>> Mark >>> >> -- > >>>>>>>>>> Read the docs: http://akka.io/docs/ > >>>>>>>>>> Check the FAQ: > http://doc.akka.io/docs/akka/current/additional/faq.html > >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user > --- > You received this message because you are subscribed to the Google Groups > "Akka User List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to akka-user+unsubscr...@googlegroups.com. > To post to this group, send email to akka-user@googlegroups.com. > Visit this group at http://groups.google.com/group/akka-user. > For more options, visit https://groups.google.com/d/optout. > -- Akka Team Typesafe - The software stack for applications that scale Blog: letitcrash.com Twitter: @akkateam -- >>>>>>>>>> Read the docs: http://akka.io/docs/ >>>>>>>>>> Check the FAQ: >>>>>>>>>> http://doc.akka.io/docs/akka/current/additional/faq.html >>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user --- You received this message because you are subscribed to the Google Groups "Akka User List" group. 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