Rialto Server Initialisation
@startuml
autonumber
participant ApplicationManager
participant RialtoServerManager
ApplicationManager -> RialtoServerManager: create(state_observer, config)
note right: config allows app manager to specify number of preloaded servers, path to RialtoApplicationSessionServer binary, startup timer and heathcheck interval
loop For num of preloaded server
RialtoServerManager -> RialtoServerManager: Generate socketpair for Rialto Application Session Server to Server Manager communication
RialtoServerManager -> RialtoApplicationSessionServer **: Spawn(server_manager_socket)
note left
Spawn preloaded Application
Session Servers to speed up app launch time.
end note
RialtoServerManager -> RialtoServerManager: Start [startup] second READY timer
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Set current_state = Uninitialised
alt RialtoApplicationSessionServer started successfully
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Uninitialised)
RialtoServerManager -> RialtoServerManager: Cancel READY timer
else Session Server initialisation failed
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Error)
RialtoServerManager -> RialtoServerManager: Cancel READY timer
RialtoApplicationSessionServer -> RialtoApplicationSessionServer !!: Exit process
else READY timer expired
RialtoServerManager -> RialtoServerManager: Kill spawned Rialto Application Session Server process
end
end
RialtoServerManager --> ApplicationManager:
@enduml |
Rialto App Startup
Rialto Application State Changes
Not Running (no server preloading)/Unitialized (server prealoding)→Inactive
@startuml
autonumber
participant ApplicationManager
participant RialtoServerManager
ApplicationManager -> RialtoServerManager: initiateApplication(application_id, AppState::Inactive, app_config)
note right: app_config allows app manager to specify the socket name to use for Rialto client/server session management and the socket name for communication with a display server
opt session_management_socket_name not specified in app_config
RialtoServerManager -> RialtoServerManager: Generate unique session_management_socket_name for Rialto Client to Rialto Application Session Server communication
end
alt There are no preloaded servers
RialtoServerManager -> RialtoServerManager: Generate socketpair for Rialto Application Session Server to Server Manager communication
RialtoServerManager -> RialtoApplicationSessionServer **: Spawn(server_manager_socket)
RialtoServerManager -> RialtoServerManager: Start [startup] second READY timer
RialtoServerManager --> ApplicationManager: OK/ERROR
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Set current_state = Uninitialised
alt RialtoApplicationSessionServer started successfully
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Uninitialised)
RialtoServerManager -> RialtoServerManager: Cancel READY timer
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Uninitialised)
RialtoServerManager -> RialtoApplicationSessionServer: SetConfiguration(session_management_socket_name, AppState::Inactive, resources, log_level)
note right
"resources" structure will specify the maximum decoder resources that the
application is permitted to use. For now it shall have a max_playback_sessions
property and a supports_web_audio flag. This may be enhanced for things like
HD/UHD, audio only etc in future.
end note
RialtoApplicationSessionServer --> RialtoServerManager:
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Create listening socket & bind to session_management_socket_name
alt State transition successful
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Set current_state = Inactive
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Inactive)
RialtoServerManager -// ApplicationManager: StateChanged(application_id, AppState::Inactive)
ApplicationManager -> RialtoServerManager: getAppConnectionInfo()
RialtoServerManager --> ApplicationManager: session_management_socket_name
else State transition failed
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Unbind/free session management socket (if created)
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Error)
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Error)
RialtoApplicationSessionServer -> RialtoApplicationSessionServer !!: Exit process
end
else Session Server initialisation failed
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Unbind/free session management socket (if created)
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Error)
RialtoServerManager -> RialtoServerManager: Cancel READY timer
RialtoApplicationSessionServer -> RialtoApplicationSessionServer !!: Exit process
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Error)
else READY timer expired
RialtoServerManager -> RialtoServerManager: Kill spawned Rialto Application Session Server process
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Error)
end
end
@enduml |
@startuml
autonumber
participant ApplicationManager
participant RialtoServerManager
ApplicationManager -> RialtoServerManager: initiateApplication(application_id, AppState::Inactive, app_config)
note right: app_config allows app manager to specify the socket name to use for Rialto client/server session management
opt Socket name not specified in app_config
RialtoServerManager -> RialtoServerManager: Generate unique session_management_socket_name for Rialto Client to Rialto Application Session Server communication
end
RialtoServerManager -> RialtoServerManager: Generate socketpair for Rialto Application Session Server to Server Manager communication
RialtoServerManager -> RialtoApplicationSessionServer **: Spawn(server_manager_socket, session_management_socket_name)
note left
Depending on configuration, Rialto Server Manager
may maintain a pool of pre-loaded Application
Session Servers in which case one of these will
be used to speed up app launch time.
end note
RialtoServerManager -> RialtoServerManager: Start [1] second READY timer
RialtoServerManager --> ApplicationManager: OK/ERROR
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Set current_state = Uninitialised
alt RialtoApplicationSessionServer started successfully
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Uninitialised)
RialtoServerManager -> RialtoServerManager: Cancel READY timer
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Uninitialised)
RialtoServerManager -> RialtoApplicationSessionServer: SetConfiguration(session_management_socket_name, AppState::Inactive, resources, log_level)
note right
"resources" structure will specify the maximum decoder resources that the
application is permitted to use. For now it shall have a max_playback_sessions
property and a supports_web_audio flag. This may be enhanced for things like
HD/UHD, audio only etc in future.
end note
RialtoApplicationSessionServer --> RialtoServerManager:
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Create listening socket & bind to session_management_socket_name
alt State transition successful
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Set current_state = Inactive
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Inactive)
RialtoServerManager -// ApplicationManager: StateChanged(application_id, AppState::Inactive)
ApplicationManager -> RialtoServerManager: getAppConnectionInfo()
RialtoServerManager --> ApplicationManager: session_management_socket_name
else State transition failed
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Unbind/free session management socket (if created)
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Error)
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Error)
RialtoApplicationSessionServer -> RialtoApplicationSessionServer !!: Exit process
end
else Session Server initialisation failed
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Unbind/free session management socket (if created)
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Error)
RialtoServerManager -> RialtoServerManager: Cancel READY timer
RialtoApplicationSessionServer -> RialtoApplicationSessionServer !!: Exit process
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Error)
else READY timer expired
RialtoServerManager -> RialtoServerManager: Kill spawned Rialto Application Session Server process
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Error)
end
@enduml |
3. socketpair is used to create the point-to-point IPC channel used for all Rialto Server Manager to Rialto Application Session Server communications
8. Application Session Server sends first message so Server Manager knows that it is now up and running
13. Session server creates the socket that the app will use for sending AV data and control respectively.
17/18. Server Manager has an API to allow the Application Manager to get the socket name that the App will use for communication with Rialto which it should fetch as soon as it is notified that Rialto has moved the app out of the Not Running state so that it can be passed to the app/container when it is launched (this is optional as the app manager can supply the socket name in step 1)
Inactive→Active
@startuml
autonumber
participant ApplicationManager
participant RialtoServerManager
participant RialtoApplicationSessionServer
ApplicationManager -> RialtoServerManager: changeSessionServerState(application_id, AppState::Active)
RialtoServerManager -> RialtoApplicationSessionServer: SetState(AppState::Active)
RialtoApplicationSessionServer --> RialtoServerManager: OK/ERROR
RialtoServerManager --> ApplicationManager: OK/ERROR
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Allocate shared memory buffer
opt State transition successful
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Set current_state = Active
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Active)
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Active)
else State transition failed
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Free shared memory buffer if allocated
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Error)
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Error)
end
@enduml |
2. RialtoServerManager will need to look up which RialtoApplicationSessionServer to which to send the notification
Not Running→Active
Same sequence as Not Running→Inactive but change target state to Active and allocate shared memory buffer after creating session management socket.
Active→Inactive
@startuml
autonumber
participant ApplicationManager
participant RialtoServerManager
participant RialtoApplicationSessionServer
ApplicationManager -> RialtoServerManager: changeSessionServerState(application_id, AppState::Inactive)
RialtoServerManager -> RialtoApplicationSessionServer: SetState(AppState::Inactive)
RialtoApplicationSessionServer --> RialtoServerManager: OK/ERROR
RialtoServerManager --> ApplicationManager: OK/ERROR
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Free any remaining CDM resources
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Free any remaining Player resources
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Unmap/free shared memory buffer
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Set current_state = Inactive
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::Inactive)
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::Inactive)
@enduml |
6. Free any Player resources means close any open GStreamer pipelines, for example those used for AV playback and/or UI audio.
Inactive→Not Running
@startuml
autonumber
participant ApplicationManager
participant RialtoServerManager
participant RialtoApplicationSessionServer
ApplicationManager -> RialtoServerManager: changeSessionServerState(application_id, AppState::NotRunning)
RialtoServerManager -> RialtoApplicationSessionServer: SetState(AppState::NotRunning)
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Close IPC connection with app
RialtoApplicationSessionServer -> RialtoApplicationSessionServer: Set current_state = NotRunning
RialtoApplicationSessionServer -// RialtoServerManager: stateChanged(AppState::NotRunning)
RialtoApplicationSessionServer -> RialtoApplicationSessionServer !!: Exit process
RialtoServerManager -// ApplicationManager: stateChanged(application_id, AppState::NotRunning)
@enduml |
6. The Session Server process should self terminate once it has sent the NotRunning notification to the Server Manager.
Active→Not Running
Not shown for brevity, but should perform all of the cleanup operations in Rialto Sessions server shown in Active→Inactive & Inactive->Not Running.
Application Management
Start Application in Inactive State
@startuml
autonumber
participant ApplicationManager
participant RialtoApplicationSessionServer
ref over ApplicationManager, RialtoApplicationSessionServer : [[#RialtoApplicationSessionManagement-NotRunning→Inactive Not Running to Inactive]]
ApplicationManager -> Application ** : Spawn(AppState::Inactive, listening_socket_name)
Application -> RialtoClient ** : Load RialtoClient library
RialtoClient -> RialtoApplicationSessionServer: Connect(rialto_listening_socket)
note right
Connect is not an API call, it is establishing IPC channel with server
end note
RialtoClient --> Application: status
Application -// ApplicationManager: stateChanged(AppState::Inactive)
@enduml |
Start Application in Running State
@startuml
autonumber
participant ApplicationManager
participant RialtoApplicationSessionServer
ref over ApplicationManager, RialtoApplicationSessionServer : [[#RialtoApplicationSessionManagement-NotRunning→Active Not Running to Active]]
ApplicationManager -> Application ** : Spawn(AppState::Running, listening_socket_name)
Application -> RialtoClient ** : load RialtoClient library
RialtoClient -> RialtoApplicationSessionServer: Connect(rialto_listening_socket)
note right
Connect is not an API call, it is establishing IPC channel with server
end note
RialtoClient --> Application:
Application -> RialtoClient: setApplicationState(Running)
RialtoClient -> RialtoApplicationSessionServer: GetSharedMemory()
RialtoApplicationSessionServer --> RialtoClient: shm_fd
RialtoClient -> RialtoClient: Map shared memory
RialtoClient --> Application: status
Application -// ApplicationManager: stateChanged(AppState::Running)
@enduml |
Switch Application from Inactive to Running State
@startuml
autonumber
participant ApplicationManager
participant RialtoApplicationSessionServer
participant Application
participant RialtoClient
ref over ApplicationManager, RialtoApplicationSessionServer : [[#RialtoApplicationSessionManagement-Inactive→Active Inactive to Active]]
ApplicationManager -> Application : NotifyNewState(AppState::Running)
Application -> RialtoClient: setApplicationState(Running)
RialtoClient -> RialtoApplicationSessionServer: GetSharedMemory()
RialtoApplicationSessionServer --> RialtoClient: shm_fd
RialtoClient -> RialtoClient: Map shared memory
RialtoClient --> Application: status
Application -// ApplicationManager: stateChanged(AppState::Running)
@enduml |
Switch Application from Running to Inactive State
@startuml
autonumber
participant ApplicationManager
participant RialtoApplicationSessionServer
participant Application
participant RialtoClient
ApplicationManager -> Application : NotifyNewState(AppState::Inactive)
Application -> RialtoClient: setApplicationState(Inactive)
RialtoClient -> RialtoClient : Free CDM & Player resources
RialtoClient -> RialtoClient: Unmap shared memory
RialtoClient --> Application: status
Application -// ApplicationManager: stateChanged(AppState::Inactive)
ref over ApplicationManager, RialtoApplicationSessionServer : [[#RialtoApplicationSessionManagement-Active→Inactive Active to Inactive]]
@enduml
|
Stop Application from Inactive State
@startuml
autonumber
participant ApplicationManager
participant RialtoApplicationSessionServer
participant Application
participant RialtoClient
ApplicationManager -> Application : NotifyNewState(AppState::NotRunning)
Application -// ApplicationManager: stateChanged(AppState::NotRunning)
Application -> RialtoClient: Unload library
RialtoClient -> RialtoClient !!:
Application -> Application !!:
ref over ApplicationManager, RialtoApplicationSessionServer : [[#RialtoApplicationSessionManagement-Inactive→NotRunning Inactive to Not Running]]
@enduml |
Stop Application from Running State
@startuml
autonumber
participant ApplicationManager
participant RialtoApplicationSessionServer
participant Application
participant RialtoClient
ApplicationManager -> Application : NotifyNewState(AppState::NotRunning)
Application -> RialtoClient: setApplicationState(Inactive)
RialtoClient -> RialtoClient : Free CDM & Player resources
RialtoClient -> RialtoClient: Unmap shared memory
RialtoClient --> Application: status
Application -// ApplicationManager: stateChanged(AppState::NotRunning)
Application -> RialtoClient: Unload library
RialtoClient -> RialtoClient !!:
Application -> Application !!:
ref over ApplicationManager, RialtoApplicationSessionServer : [[#RialtoApplicationSessionManagement-Active→NotRunning Active to Not Running]]
@enduml |
Example Application Switch Sequences
Active / Inactive Application Switch
This following diagram shows a typical sequence for when the Application Manager needs to make an application active when a currently running application is using the Player resources that the new application requires. The application manager therefore moves the current application into the inactive state to free up the resources and once that is complete switches the new application into the active state so that it can acquire those resources.
@startuml
autonumber
participant ApplicationManager
participant RialtoServerManager
note across : First make App_1 Inactive
ref over ApplicationManager, RialtoServerManager : [[#RialtoApplicationSessionManagement-Active→Inactive Active->Inactive(app_id_1)]]
note across
Once Application Manager has received
the state change event to Inactive for
app_id_1 it can then make App_2 Active
end note
ref over ApplicationManager, RialtoServerManager : [[#RialtoApplicationSessionManagement-Inactive→Active Inactive->Active(app_id_2)]]
@enduml |