Cherry xAPP Startup

@startuml
Autonumber
Skinparam sequenceArrowThickness 2
skinparam ParticipantPadding 5
skinparam BoxPadding 10

Box "SMO/Non-RT RIC Framework" #gold
   participant NFO as "NF Orchestration" <<INT OTF>>
   Boundary MC as "Model Catalog" <<SMO MVC State Manager>>
   Boundary VI as "Virtual Inventory" <<SMO MVC State Manager>>
   Boundary IC as "Instance Config" <<SMO MVC State Manager>>
end box

Box "O-Cloud Platform"  #lightseagreen
   participant IMS as "Cloud Manager"
   participant DMS as "Deployment Manager"
End box

Box "O-RAN" #NavajoWhite
   Participant AppMgr as "xAPPMgr" <<RICPLT>>
End box

Box "Near-RT RIC\napplication execution environment " #PapayaWhip
   participant App as "Application" <<RICAPP>>
   participant Sidecar as "rAPP Sidecar" <<RICAPP>>
end box

== Building Block Identity & Legend ==

note over NFO, Sidecar #royalblue
**<color: yellow>Building Block : xAPP Startup </color>**
end note

== Assumptions and Prerequisites ==

note over NFO, DMS #darkorange
Application and its sidecar were just created/started by the DMS.
end note

== Begin Building Block ==

Note Right of NFO
Message numbers are discontinous
In order to match same message numbers
In rAPP startup
End note

     Sidecar <-> App : connect
     Sidecar -> AppMgr : PUT ../xAPPs/<myAPPID>
     Note right of AppMgr
     Registration returns record contain:
        xAPPID,
        xAPPRegistrationTime,
        xAPPRestarts,
        configurationID
     end note

     alt if xAPPRestarts > 0 and ConfigurationID is not null then
        Sidecar -> AppMgr : GET ../configs/<configurationdID>
Autonumber 5
        Sidecar -> App : Config(configuration)
     Else if ConfigurationID is Null and xAPPRestarts > MaxStartAttempts then
        Sidecar -> DMS : Fatal Error, don't restart
     Else
        Sidecar -> App : Config(configMap.configuration)
        Alt If successful then
           Sidecar -> AppMgr : POST ../configSchemas {configMap.configurationSchema}
           AppMgr -> AppMgr :
           Note left: xAPPMgr needs to incorporate xAPP YANG leafs into RIC Config
           Sidecar -> AppMgr : POST ../configurations {configMap.configuration}
           AppMgr -> AppMgr :
           Note Left : Create MOI and populate ConfigDB
           Opt Stretch goal for CM Notify
           AppMgr -> NFO : <<O1>> MOI Create Notification
           End
        Else
           Sidecar -> App : Restart
           App -> DMS : Internal Error, restart
           Sidecar -> DMS : Internal Error, restart
        End if
     End if

@enduml