If you are running an application and there are lot of chances for a huge traffic to come in future, a single server would not be capable to handle this.
In that case you would have two choices:
A) Replace existing server with an advance server with better configuration
B) Building a global node in the cluster to be used by other nodes.
We know that first option is not a permanent solution. So lets move to second option.
I have created a Login Application with Things To Do functionality using Lift in Scala.
In this application, I have added a chat module using LiftComet Actor and AkkaActor.
In the Chat Module, I have implemented cluster functionality, so that application could be accessed remotely.
So the concept is: there would be one Akka Actor on central server and this central akka actor would be used by other comet actors, whether they are on the same server or different server.
Since Lift has its own actor model, so I have created a bridge between LiftComet and Akka Actor, so that Akka actor would be able send message to comet, once comet has been set.
To learn bridging concept in deep, go here : http://riteofcoding.blogspot.in/2011/05/beyond-chat-lift-comet-and-akka.html
In this application, there is one controller
object CometAlertController extends Loggable {
This controller would give central actor reference, if exists, otherwise create a new central actor, if not exist. Here I have created a central actor with hard-coded configuration,
You can change this according to your application.
As you can see in the above method, first controller will ping to central actor by sending a Ping message.
If actor exists, it would send a reply otherwise a TimeoutException would be thrown. If TimeoutException is caught in catch block, controller would create a new central actor.
There is GlobalActorSystem.scala
to create single actor system throughout the application.
For the chat module, there is Chat.scala
, which is comet actor and AkkaAlertActor
is Akka Actor.
The comet actor and akka actor would communicate with each other using BridgeActor
, which works as a bridge between comet and akka.
Since In a remote application, actors would pass message throughout the network, so those messages must be serialized. To serialized those messages, I have implemented Akka-Kryo-Serialization.
How to run application:-
A) Clone code from https://github.com/romix/akka-kryo-serialization.
B) Run sbt compile publish-local
C) Now clone https://github.com/knoldus/Lift_UserLogin_Template
D) Run sbt ~container:start
How to test in remote environment:
A) Open a terminal and run sbt ~container:start
.
B) Open build.sbt and change
port in container.Configuration := 8081
C) Open another terminal and run sbt ~container:start
.
D) Register yourself and login and Enjoy chat.
You would be able to do chat remotely from different JVMs. Check and let me know your feedback. Your feedback would be highly appreciated.
Reblogged this on Agile Mobile Developer.
Regards
Congratulations, your article is very interesting
This topic is just what I was looking for
Download your project to test it, but when compiling shows me the following error
[error]
../Lift_UserLogin_Template/src/main/scala/code/lib/NettyPort.scala:15: class RemoteActorRefProvider in package remote cannot be accessed in package akka.remote
[error] case r: RemoteActorRefProvider => r.transport.address.port.get.asInstanceOf[Int]
[error] ^
[error]
../Lift_UserLogin_Template/src/main/scala/code/lib/NettyPort.scala:15: value transport is not a member of akka.actor.ActorRefProvider
[error] case r: RemoteActorRefProvider => r.transport.address.port.get.asInstanceOf[Int]
[error] ^
[error] two errors found
How I can fix it?
Hi Santo,
Thanks for your feedback. I just saw your message. I would look into this issue and get back to you with the solution very soon.
Hi Santo,
I have fixed the issue. Please check and let me know if still you are facing any issue.
Make sure you have SBT 0.13.