Summary

Create C++20 module files for messaging_system as part of the Tier 5 (Application) layer.

Parent Epic

Part of kcenon/common_system#256 (C++20 Module Migration - Cross-System Preparation)

Prerequisites

All lower tier modules must be completed first:

• [MODULE] Create C++20 module files for kcenon.common common_system#269 - common_system module (Tier 0)
• [MODULE] Create C++20 module files for kcenon.thread thread_system#371 - thread_system module (Tier 1)
• [MODULE] Create C++20 module files for kcenon.container container_system#222 - container_system module (Tier 1)
• [MODULE] Create C++20 module files for kcenon.logger logger_system#275 - logger_system module (Tier 2)
• [MODULE] Create C++20 module files for kcenon.network network_system#395 - network_system module (Tier 4)
• [MODULE] Create C++20 module files for kcenon.database database_system#314 - database_system module (Tier 3)

Proposed Module Structure

// Primary module interface
export module kcenon.messaging;

import kcenon.common;           // Required
import kcenon.thread;           // Required
import kcenon.container;        // Required
import kcenon.logger;           // Required
import kcenon.network;          // Required
import kcenon.database;         // Required

export import kcenon.messaging.core;
export import kcenon.messaging.protocols;
export import kcenon.messaging.serialization;

Module Partitions

File Structure

src/modules/
├── messaging.cppm           # Primary module interface
├── core.cppm                # Core partition
├── protocols.cppm           # Protocols partition
└── serialization.cppm       # Serialization partition

CMake Configuration

cmake_minimum_required(VERSION 3.28)
set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_SCAN_FOR_MODULES ON)

add_library(kcenon_messaging)
target_sources(kcenon_messaging
    PRIVATE FILE_SET CXX_MODULES
    FILES
        src/modules/messaging.cppm
        src/modules/core.cppm
        src/modules/protocols.cppm
        src/modules/serialization.cppm
)

Tasks

• Wait for all dependency modules (Tier 0-4) completion
• Create module directory structure
• Create module files
• Update CMakeLists.txt for module support
• Verify no circular module dependencies
• Update all tests to use modules
• Update documentation

Acceptance Criteria

• Module builds successfully with CMake 3.28+
• Successfully imports all 6 dependent modules
• All existing tests pass with module
• No circular dependencies
• Header-based build still works (transition period)

Migration Timeline

This is Phase 2 work (Release N+4) per EPIC:

• This is the final module in the dependency chain
• Blocked by: All Tier 0-4 modules

Related

• C++20 Module Migration Epic ([EPIC] C++20 Module Migration - Cross-System Preparation common_system#256)