DubSub - Distributed PubSub with Akka Cluster
Add the following to your Build.scala
val appDependencies = Seq(
"uk.co.panaxiom" %% "play-dubsub" % "0.4-SNAPSHOT"
)
val main = play.Project(appName, appVersion, appDependencies).settings(
resolvers += Resolver.url("Alex's GitHub Repository", url("http://alexanderjarvis.github.com/snapshots/"))(Resolver.ivyStylePatterns)
)Add to your conf/play.plugins file (and create if it does not exist), where 500 is the priority that you can adjust relative to other plugins.
500:uk.co.panaxiom.dubsub.DubSubPlugin
You will need to define an actor which responds to Subscribe, Unsubscribe and Publish in order to receive messages from DubSub:
import uk.co.panaxiom.dubsub._
class SocketActor extends Actor {
def receive = {
case Subscribe(channel) => Logger.info("Subscribed to dubsub channel " + channel)
case Unsubscribe(channel) => Logger.info("Unsubscribed to dubsub channel " + channel)
case Publish(channel, message) => Logger.info("Publish from dubsub " + channel + " message " + message)
}
}From within this actor you can send messages to DubSub like the following:
val dubsub = DubSubPlugin.dubsub
// Subscribes this actor to messages published to the channel with "topic"
dubsub ! Subscribe("topic")
// Unsubscribes this actor from "topic"
dubsub ! Unsubscribe("topic")
// Publishes a message to all subscribers of "topic" (across all cluster nodes)
dubsub ! Publish("topic", "message")Set the remote port of at least your first seed node as a runtime property. Other nodes can be started without this and will pick a random port.
play stage
target/start -Ddubsub.akka.remote.netty.tcp.port=2551
You can specify the seed-nodes of the cluster in your application.conf:
dubsub {
akka {
cluster {
seed-nodes = [
"akka.tcp://DubSubSystem@127.0.0.1:2551",
"akka.tcp://DubSubSystem@127.0.0.1:2552"]
}
}
}
Play comes with a websocket-chat example, which has been enhanced with DubSub: websocket-chat-dubsub