Source: https://github.com/mikolak-net/akka-intro-prez

1. An Introduction to Akka
Mikołaj Koziarkiewicz

2. Akka - what is it? 1/2
a platform,
"for building highly concurrent, distributed, and resilient message-driven
applications on the JVM."[1],
based on the actor model.

3. Akka - what is it? 2/2
platform has a lot of specialized extensions
all based on the actor core
goal of the presentation:
explain the core

4. Actor model - what is it?
actor: unit of computation
actors build actor systems
quite "old" (1973).[2]

5. Anatomy of an Akka Actor - intro 1/2
class MyActor extends Actor {
def receive = {
case Something => //...
}
}

6. Anatomy of an Akka Actor - intro 2/2

7. My first Akka Actor™
class HaiActor extends Actor {
def receive: Receive = {
case target: ActorRef => target ! "Hello!"
case "Hello!" => sender ! "OHAI"
case "OHAI" => println(s"$self: got OHAI from
$sender")
}
}
Where:
type Receive = PartialFunction[Any, Unit]

8. My first Akka Actor™ - example

9. Anatomy of an Akka Actor - hierarchy

10. Akka actor model - lifecycle & hierarchy
Purpose:
division of labor
supervision:
each actor has lifecycle
special hooks - preStart, preRestart, postStop
allow for e.g. self-init
"parent" controls how it reacts to failure

11. Hierarchy - example

12. Akka - guarantees
an actor processes one message at a time,
a message will be delivered at most 1 times,
messages are ordered by sender

13. Guarantee takeaways
don’t pass mutable state,
use services to ensure send:
contex.scheduler
persistence

14. Testing
Akka Testkit
Features:
can run special 1-thread dispatcher
asserts for getting msgs
TestProbe

15. Remoting
Simple remoting:
e.g. "akka.tcp://remote@freund.de:1337
/user/actorName"
remote creation as well

16. Talking to actor system
Custom:
ask pattern
ask(actoRef, request)(timeout): Future
Many others (also builtin)

17. Summary
Akka - actor model on the JVM
alternative way to handle
concurrency
distribution
declared guarantees
make reasoning easier

18. THANK YOU!
The End
Doc link:
http://doc.akka.io/docs/akka/current/scala.html
Bibliography
http://akka.io , retrieved 2015-04-20
https://en.wikipedia.org/wiki/History_of_the_Actor_model , retrieved
2015-04-12