Carbon Offset Trading Platform

A blockchain-enabled carbon offset trading platform that connects project developers with willing buyers. This platform allows project developers to list their carbon offset projects and enables buyers to purchase verified carbon credits through blockchain transactions.

Features

For Project Developers

• Register as a project developer
• Create and manage carbon offset projects
• Upload project verification documents
• Track project performance and sales
• Integrate with blockchain for tokenization

For Buyers

• Register as a buyer
• Browse verified carbon offset projects
• Purchase carbon credits
• Link blockchain wallets for transactions
• Track purchase history and carbon offset ownership

Blockchain Integration

• Wallet linking support (Ethereum-compatible)
• Smart contract integration for carbon credit tokens
• Transaction verification and tracking
• Secure blockchain-based ownership records

Tech Stack

• Backend: Node.js with Express.js and TypeScript
• Database: SQLite with Prisma ORM
• Authentication: JWT tokens with bcrypt password hashing
• Blockchain: Web3.js and Ethers.js for Ethereum integration
• Validation: Joi for request validation
• Security: Helmet, CORS, Rate limiting

Project Structure

├── src/
│   ├── server.ts           # Express application entry point
│   ├── types/              # TypeScript type definitions
│   │   └── index.ts        # Main types and interfaces
│   ├── routes/             # API endpoints
│   │   ├── auth.ts         # Authentication endpoints
│   │   ├── wallet.ts       # Wallet management endpoints
│   │   ├── projects.ts     # Project management endpoints
│   │   └── trading.ts      # Trading and marketplace endpoints
│   ├── middleware/         # Express middleware
│   │   ├── auth.ts         # Authentication middleware
│   │   ├── validation.ts   # Request validation middleware
│   │   ├── security.ts     # Security middleware
│   │   └── error.ts        # Error handling middleware
│   ├── services/           # Business logic services
│   │   ├── blockchain.ts   # Blockchain integration
│   │   └── wallet.ts       # Wallet management
│   └── utils/              # Utility functions
│       ├── database.ts     # Database connection and utilities
│       └── auth.ts         # Authentication utilities
├── prisma/
│   └── schema.prisma       # Database schema
├── storage/                # Application storage directory
│   └── db/                 # SQLite database files
├── package.json            # Node.js dependencies and scripts
├── tsconfig.json          # TypeScript configuration
└── .env.example           # Environment variables template

Installation

1. Install dependencies:

npm install

2. Set up environment variables:

cp .env.example .env
# Edit .env with your configuration

3. Generate Prisma client and run migrations:

npm run db:generate
npm run db:migrate

Running the Application

Development

Start the development server with hot reload:

npm run dev

Production

Build and start the production server:

npm run build
npm start

The application will be available at:

• API: http://localhost:8000
• Health Check: http://localhost:8000/health
• API Documentation: http://localhost:8000/api/docs

Environment Variables

Variable	Description	Required	Default
NODE_ENV	Environment mode	No	development
PORT	Server port	No	8000
JWT_SECRET	JWT token secret	Yes	-
DATABASE_URL	SQLite database file path	No	file:./storage/db/database.db
BLOCKCHAIN_RPC_URL	Ethereum RPC endpoint	No	http://localhost:8545
CORS_ORIGIN	CORS allowed origins	No	*

API Endpoints

Authentication

• POST /api/auth/register - Register new user (developer or buyer)
• POST /api/auth/login - User login

Wallet Management

• POST /api/wallet/link - Link blockchain wallet to user account
• DELETE /api/wallet/unlink - Unlink wallet from user account
• GET /api/wallet/info - Get wallet information and balance
• POST /api/wallet/generate-test-wallet - Generate test wallet for development

Project Management (Developers)

• POST /api/projects/ - Create new carbon offset project
• GET /api/projects/my-projects - Get developer's projects
• PUT /api/projects/{project_id} - Update project
• DELETE /api/projects/{project_id} - Delete project

Marketplace & Trading

• GET /api/projects/ - Browse all available projects
• GET /api/projects/{project_id} - Get project details
• POST /api/trading/purchase - Purchase carbon offsets
• GET /api/trading/my-transactions - Get user's transactions
• GET /api/trading/marketplace/stats - Get marketplace statistics

System

• GET / - Platform information
• GET /health - Health check endpoint

Database Schema

Users

• User authentication and profile information
• Wallet linking for blockchain integration
• User types: DEVELOPER or BUYER

Carbon Projects

• Project details and metadata
• Verification status and documents
• Credit availability and pricing
• Blockchain contract information

Carbon Offsets

• Individual carbon credit tokens
• Serial numbers and vintage years
• Blockchain token IDs and hashes
• Ownership tracking

Transactions

• Purchase records and blockchain transactions
• Transaction status and confirmation details
• Gas usage and block information

Development

Database Migrations

Generate Prisma client:

npm run db:generate

Create and apply migrations:

npm run db:migrate

View database in Prisma Studio:

npm run db:studio

Code Quality

Run linting:

npm run lint

Fix linting issues:

npm run lint:fix

Build TypeScript:

npm run build

Testing Wallet Integration

Use the test wallet generation endpoint to create wallets for development:

curl -X POST http://localhost:8000/api/wallet/generate-test-wallet

Security Features

• JWT-based authentication with secure token generation
• Password hashing with bcrypt (12 rounds)
• Role-based access control (DEVELOPER/BUYER)
• Rate limiting and CORS protection
• Helmet security headers
• Input validation with Joi
• Blockchain wallet verification
• Transaction signing and verification

Production Deployment

1. Set production environment variables in .env
2. Build the application: npm run build
3. Start the production server: npm start
4. Ensure database is properly migrated
5. Configure reverse proxy (nginx/Apache)
6. Set up SSL certificates
7. Configure firewall and security groups

Contributing

1. Follow TypeScript best practices
2. Use the existing code structure and patterns
3. Add comprehensive input validation
4. Include proper error handling
5. Update documentation for API changes
6. Test blockchain integration thoroughly
7. Follow the established commit message format

License

This project is part of a carbon offset trading platform implementation.