Proxy/Skeleton Base

This unit provides the proxy- and skeleton-facing base types that generated service-specific middleware bindings inherit from.

It owns initialization, request/header generation, event and attribute distribution, and lifecycle checks for the proxy/skeleton communication API.

Class Diagram

' ******************************************************************************* ' Copyright (c) 2026 BMW AG ' ' This program and the accompanying materials are made available under the ' terms of the Apache License Version 2.0 which is available at ' https://www.apache.org/licenses/LICENSE-2.0 ' ' SPDX-License-Identifier: Apache-2.0 ' ******************************************************************************* @startuml proxy_skeleton_base title Proxy/Skeleton Base - Class Diagram skinparam classFontSize 14 skinparam shadowing false left to right direction namespace middleware { namespace core <<domain>> { class TransceiverBase <<base>> { +getInstanceId(): uint16_t +getServiceId(): uint16_t +getAddressId(): uint8_t +setAddressId(addressId: uint8_t) +onNewMessageReceived(msg: Message): HRESULT +isInitialized(): bool +sendMessage(msg: Message): HRESULT +getSourceClusterId(): uint8_t } class ProxyBase <<client-side>> { +generateMessageHeader(memberId: uint16_t, requestId: uint16_t): Message +sendMessage(msg: Message): HRESULT #unsubscribe(serviceId: uint16_t) #checkCrossThreadError(initId: uint32_t) #initFromInstancesDatabase(instanceId: uint16_t, sourceCluster: uint8_t): HRESULT } class SkeletonBase <<server-side>> { +sendMessage(msg: Message): HRESULT +getClusterConnections(): span<IClusterConnection*> #unsubscribe(serviceId: uint16_t) #checkCrossThreadError(initId: uint32_t) #initFromInstancesDatabase(instanceId: uint16_t): HRESULT } class EventSender { +send(data: T, memberId: uint16_t): HRESULT +send(memberId: uint16_t): HRESULT } class ProxyAttributeBase <<template>> { +get(attrCb: GetterCallback): expected<uint16_t, HRESULT> +freeAll() +updateTimeouts() +cancelGetterRequest(requestId: uint16_t): HRESULT +answerGetterRequest(msg: Message) } class ProxyEventBase <<template>> { +setReceiveHandler(callback: OnFieldChangedCallback) +unsetReceiveHandler() } class SkeletonEvent <<template>> { +send(data: Type): HRESULT } class ProxyMethod <<template>> { +callMethod(...): expected<uint16_t, HRESULT> +answerRequest(msg: Message) +cancelRequest(requestId: uint16_t): HRESULT +freeAll() +updateTimeouts() } class ProxyMethodImpl { #obtainFuture(): Future* #futureMatchingRequestId(msg: Message): Future* } } } ProxyBase ..|> middleware.core.TransceiverBase SkeletonBase ..|> middleware.core.TransceiverBase EventSender --> SkeletonBase : broadcasts via ProxyAttributeBase --> ProxyBase : uses ProxyAttributeBase --> ProxyMethod : uses for getter requests ProxyMethod --|> ProxyMethodImpl ProxyEventBase --> ProxyBase : registered on SkeletonEvent --> EventSender : uses @enduml