exhibit-d.scala

// kinja-service library
 
class SsoService extends ApiService {
    def authorByToken(token: String): Author = {
        lookupAuthorInDatabase(token)
    }
}

trait SsoServiceContract {
    
    abstract class AuthorByToken {
        def apply(token: String): Author
    }
    
}
 
class InvitesService extends Service {
    def invite(token: String, invitee: Author, ssoServiceCallContract: SsoServiceContract#AuthorByToken): Unit = {
        val inviter = ssoServiceCallContract.apply(token)
        saveInvitationToDatabase(inviter, invitee)
    }
}
 
case class InviteMessage(token: String, invitee: Author)
 
 
 
// kinja-core application
 
object SsoService extends service.SsoService
 
object SsoServiceContract extends service.SsoServiceContract {
    
    class AuthorByTokenImpl extends AuthorByToken {
        def apply(token: String) = SsoService.authorByToken(token)
    }
    
}
 
object InvitesService extends service.InvitesService

import service.model.InviteMessage

class InvitesActor extends Actor {
    
    def receive = {
        case InviteMessage(token, invitee) => InvitesService.invite(token, invitee, SsoServiceContract.AuthorByTokenImpl)
    }
    
}
 
val invitesActor = akka.actor.ActorSystem("kinja-core").actorOf(Props(classOf[InvitesActor], "invites-actor"))
 
 
 
// kinja-mantle application
 
import service.model.InviteMessage
 
object InvitesApiClient {
    def invite(token: String, invitee: Author): Unit = {
        val invitesService = context.actorSelection("akka.tcp://kinja-core@localhost:2552/user/invites-actor")
        invitesService ! InviteMessage(token, invitee)
    }
}