Usage

Application runs inside Linux Terminal Emulator to:

• find users on LAN,
• chat with other people on LAN

The tmux terminal multiplexer was used to create program interface.

Assumptions

Application was written with the following assumptions:

• each username is unique per PC's network interface
• each user in the LAN has the same local time on the system
• only one user can run an application per IP address interface
• no centralized server
• no support for IPv6 and TLS
• terminal emulator window resizing is not supported
• ASCII set is the only supported set of characters
• messages are ephemeral, no storage

Installation

cmake -B build
cmake --build build --parallel 4
cmake --install build --prefix install

Used frameworks, tools and concepts

• C++ Multithreading
• CMake
• Google Protocol Buffers
• Google gRPC
• Google Test
• Bash
• Inter-Process Communication (message queue, named pipe, shared memory)
• Docker
• VirtualBox
• Networking
• PlantUML
• Valgrind
• Minitrace
• Spdlog

Debugging

Use Visual Studio Code (with C/C++ Extension Pack extension) to debug unit tests. Specify -DCMAKE_BUILD_TYPE=Debug to generate trace and log files in /tmp directory on runtime.

Test strategy

Application was tested using:

• Unit tests,
• Integration tests - so called auto tests,
• E2E tests - using up to three docker containers and virtual networks,
• Manual tests - using up to three VMs and virtual networks

Future extensions and support

• support for other character encodings
• support for IPv6 and TLS
• messages rollback after shutdown based on trusted peer (requires TLS)
• utils unit tests
• engine auto tests