Chord - Discord-like Real-Time Chat Application

Purpose: Main project overview, features, and quick start guide. For detailed documentation, see the specific README files below.

Note: The project final report is available in the root directory: 21290270.pdf

Project Presentation Video: YouTube

Chord is a modern, real-time chat application inspired by Discord, built with .NET 9 and React.

🌐 Live Demo: chord.borak.dev

Documentation

Document	Description
backend/README.md	API endpoints, SignalR, LiveKit, mobile integration
frontend/README.md	React components, state management, UI
docs/DEPLOYMENT.md	Deployment scenarios, CI/CD, production setup
docs/ER_DIAGRAM.md	Database schema ER diagram (Mermaid)
docs/DEMO.md	Complete demo scenario covering all features
docs/LOAD-TESTING.md	K6 load testing guide (1K concurrent users)
chord_roadmap.md	Development phases and feature roadmap

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Features

• Real-Time Messaging - Instant messaging with SignalR WebSockets
• Guilds & Channels - Discord-like servers with text and voice channels
• Voice & Video Chat - LiveKit SFU for 10+ users with speaking indicators
• Direct Messages - 1-1 private messaging with unread tracking
• Friends System - Add friends, accept/decline requests, block users
• File Upload - Images, videos, documents (25MB limit)
• Profile Photos - Avatars and guild icons (auto-resized to 256x256 WebP)
• Role-Based Permissions - Custom roles with granular permissions
• Message Features - Reactions, pinning, editing, deletion, @mentions
• User Presence - Online, Idle, DND, Invisible, Offline statuses
• Guild Invites - Shareable invite links
• Typing Indicators - See who's typing
• Unread Tracking - Per-channel and per-DM unread counts
• Audit Logs - Track guild actions (owner-only, paginated)

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Tech Stack

Layer	Technologies
Backend	.NET 9, EF Core 9, SQL Server, Redis, SignalR, JWT
Frontend	React 18, TypeScript, Vite, Redux Toolkit, Tailwind CSS
Voice/Video	LiveKit (WebRTC SFU), Coturn (STUN/TURN)
Storage	MinIO (S3-compatible object storage)
CI/CD	GitHub Actions, Docker, Blue-Green deployment

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Quick Start

Prerequisites

• .NET 9 SDK
• Node.js 18+ (or nvm)
• Docker & Docker Compose
• Git

Automated Setup (Recommended)

git clone https://github.com/brckfrc/chord.git
cd chord

# Development (localhost + LAN access)
./setup-env.sh dev

# Production (domain + SSL + CI/CD)
./setup-env.sh prod

The script automatically:

• Installs dependencies (Docker, Node.js, dotnet-ef)
• Generates secure secrets
• Starts all Docker services
• Runs database migrations
• (Production) Sets up GitHub Actions CI/CD

After Setup

./start-dev.sh   # Start all services
./stop.sh        # Stop all services
./update-ip.sh   # Quick IP change (laptop users)

Manual Setup

See backend/README.md and frontend/README.md for manual setup instructions.

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Project Structure

chord/
├── backend/                       # .NET 9 Web API
│   ├── Controllers/               # API endpoints
│   ├── Hubs/                      # SignalR (ChatHub, PresenceHub)
│   ├── Services/                  # Business logic
│   ├── docker-compose.dev.yml     # Development infrastructure
│   ├── docker-compose.standalone.yml # Backend standalone (deprecated)
│   └── README.md                  # Backend documentation
│
├── frontend/                      # React + TypeScript
│   ├── src/
│   │   ├── components/            # UI components
│   │   ├── store/                 # Redux state
│   │   └── hooks/                 # Custom hooks
│   └── README.md                  # Frontend documentation
│
├── scripts/                       # Deployment scripts
│   ├── deploy.sh                  # Blue-green deployment
│   ├── rollback.sh                # Rollback utility
│   └── setup-infra.sh             # Infrastructure setup automation
│
├── docs/                          # Documentation
│   ├── DEPLOYMENT.md              # Deployment overview & decision tree
│   ├── DEPLOYMENT-STANDALONE.md   # Fresh server + Caddy guide
│   ├── DEPLOYMENT-STANDARD.md     # Existing reverse proxy guide
│   ├── DEPLOYMENT-YUNOHOST.md     # YunoHost-specific guide
│   └── ER_DIAGRAM.md              # Database ER diagram (Mermaid)
│
├── docker-compose.standalone.yml  # Standalone deployment (Caddy + blue-green)
├── docker-compose.deploy.yml      # Standard VPS deployment (blue-green)
├── docker-compose.yunohost.yml    # YunoHost overrides (security)
│
├── setup-env.sh                   # Automated setup script
├── start-dev.sh                   # Start development
├── stop.sh                        # Stop all services
└── chord_roadmap.md               # Development roadmap

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Development

Initial Setup

git clone https://github.com/brckfrc/chord.git
cd chord
npm install      # Installs husky (pre-commit hooks)

Pre-commit Hooks

This project uses Husky + lint-staged for automatic code quality checks:

git commit → pre-commit hook → ESLint on staged files
                                    ↓
                          Error? → Commit blocked ❌
                          Only warnings? → Commit OK ✅

• Errors block the commit (must be fixed)
• Warnings are allowed (fix later)

Commit Conventions

Use Conventional Commits format:

feat: add new feature
fix: fix bug
chore: update dependencies
docs: update documentation
style: format code
refactor: refactor code
test: add tests

Skip CI/CD:

git commit -m "docs: update README [skip ci]"
git commit -m "chore: cleanup [ci skip]"

Supported skip keywords: [skip ci], [ci skip], [no ci], [skip actions], [actions skip]

Backend

cd backend
dotnet watch run              # Hot reload
dotnet ef migrations add Name # New migration
dotnet ef database update     # Apply migrations

Frontend

cd frontend
npm install      # Install dependencies
npm run dev      # Development server
npm run build    # Production build
npm run lint     # ESLint

Testing

cd frontend
npm run test:e2e      # Run Playwright E2E tests (Login → Guild → Message)
npm run test:e2e:ui   # Run tests in UI mode

E2E tests use an isolated Docker Compose test environment. See frontend/README.md for details.

Load Testing:

npm run test:load        # Full load test (1K concurrent users, ~8 minutes)
npm run test:load:smoke  # Smoke test (10 users, 30 seconds)

Load tests validate API performance under high concurrent load. See docs/LOAD-TESTING.md for details.

API Documentation

• Swagger UI: http://localhost:5049/swagger
• Health Check: http://localhost:5049/health

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Deployment

Three deployment scenarios with blue-green support:

Scenario	When to Use	Guide
Standalone	Fresh server, no existing infrastructure	DEPLOYMENT-STANDALONE.md
Standard VPS	Have Nginx, Traefik, or Apache	DEPLOYMENT-STANDARD.md
YunoHost	Using YunoHost for self-hosting	DEPLOYMENT-YUNOHOST.md

YunoHost Note: YunoHost uses an automated blue-green strategy where:

• Blue stack (5002/3002): Staging environment - deploy new versions here first
• Green stack (5003/3003): Production - Nginx always routes to green
• After blue stack health checks pass, automatically deploy to green, then stop blue
• No manual Nginx config changes needed (Nginx is static, always points to green)

Quick Start:

# Standalone (includes Caddy)
docker compose -f docker-compose.standalone.yml --profile infra up -d
docker compose -f docker-compose.standalone.yml --profile blue --profile caddy up -d

# Standard VPS (bring your own reverse proxy)
docker compose -f docker-compose.deploy.yml --profile infra up -d
docker compose -f docker-compose.deploy.yml --profile blue up -d

# YunoHost (with security overrides)
docker compose -f docker-compose.deploy.yml -f docker-compose.yunohost.yml --profile infra up -d
docker compose -f docker-compose.deploy.yml -f docker-compose.yunohost.yml --profile blue up -d

See docs/DEPLOYMENT.md for the decision tree and detailed instructions.

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Security

• BCrypt password hashing
• JWT authentication with refresh tokens
• Rate limiting (100 req/min)
• CORS protection
• Input validation (FluentValidation)
• SQL injection protection (EF Core)

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License

MIT License - see LICENSE file.

Contributing

Contributions welcome! Please open an issue or submit a Pull Request.