@startuml
title Alternative B: Event-based notification between RouDi and User App

participant RouDi
participant UserAppA
participant UserAppB

UserAppA->RouDi:  getMiddlewareInterface() / CREATE_INTERFACE
activate UserAppA
RouDi->UserAppA: CREATE_INTERFACE_ACK
deactivate UserAppA

RouDi->UserAppA: handleInterfaces() sends complete service registry
activate UserAppA

note right: Only react on CaproMessageSubType::SERVICE

UserAppB->RouDi: offer()
loop every 100ms
    RouDi->RouDi: doDiscovery()

    activate RouDi
    RouDi->RouDi: doDiscoveryForPublisherPorts()
    alt CaproMessage received
        RouDi->RouDi: sendToAllMatchingInterfaces()
        RouDi->UserAppA: dispatchCaProMessage()
    end
end
deactivate RouDi
UserAppA->UserAppA: wake up from wait()
deactivate UserAppA

@enduml