Agri-Trace: Blockchain-Based Agricultural Supply Chain Traceability

A comprehensive smart contract system for tracking agricultural products from farm to consumer, ensuring transparency, fair pricing, and fraud detection.

🌾 Overview

Agri-Trace is a decentralized application built on Ethereum that enables:

• End-to-end traceability of agricultural products through the supply chain
• QR code verification for consumers to verify product authenticity
• Fair pricing mechanisms to protect farmers with minimum support prices
• Fraud detection using statistical analysis and pattern recognition
• Payment escrow for secure transactions between supply chain participants
• Consumer-friendly interface for easy product verification

📋 Table of Contents

• Features
• Architecture
• Contracts
• Installation
• Testing
• Deployment
• Usage
• Security
• Contributing

✨ Features

Core Functionality

• Product Tracking: Track products through 9 distinct stages (Planted → Growing → Harvested → Processed → Packaged → In Transit → Distributed → Retail → Sold)
• Quality Monitoring: Record temperature, humidity, and quality scores at each stage
• IPFS Integration: Store product documentation and certificates on IPFS
• Role-Based Access Control: Secure access with farmer, distributor, retailer, and regulator roles

Advanced Features

• QR Code Registry: Link physical QR codes to blockchain product records
• Fair Pricing: Enforce minimum support prices with farmer rating bonuses
• Fraud Detection: Detect price anomalies and timing violations using statistical methods
• Payment Escrow: Secure conditional payments with automatic execution
• Consumer Interface: Simplified verification for end consumers

🏗️ Architecture

The system consists of 6 main smart contracts:

┌─────────────────────┐
│ AgricultureSupplyChain │ (Core tracking)
└──────────┬──────────┘
           │
    ┌──────┴──────┬──────────────┬──────────────┐
    │            │              │              │
┌───▼───┐  ┌────▼────┐  ┌──────▼──────┐  ┌───▼──────┐
│Payment│  │QR Registry│  │Fair Pricing │  │  Fraud   │
│Contract│  │          │  │  Contract   │  │Detection │
└───────┘  └──────────┘  └─────────────┘  └──────────┘
    │            │              │              │
    └────────────┴──────────────┴──────────────┘
                    │
            ┌───────▼────────┐
            │ConsumerInterface│
            └─────────────────┘

📄 Contracts

1. AgricultureSupplyChain

Core contract for product tracking

• Manages product lifecycle through 9 stages
• Stores quality data and IPFS hashes
• Handles ownership transfers
• Role-based stage updates

2. QRCodeRegistry

QR code management

• Registers QR codes linked to products
• Validates QR code authenticity
• Tracks QR code status (active/inactive)

3. PaymentContract

Escrow and payment handling

• Creates conditional payments
• Manages escrow balances
• Automatic payment execution
• Secure fund transfers

4. FairPricingContract

Price protection for farmers

• Enforces minimum support prices
• Farmer rating system
• Market price validation
• Volatility protection

5. FraudDetectionContract

Advanced fraud detection

• Price anomaly detection using statistical methods
• Timing violation detection
• Actor blacklisting
• Comprehensive risk scoring

6. ConsumerInterface

Consumer-friendly verification

• Simple product verification by ID or QR code
• Farmer reputation display
• Product journey tracking
• Batch verification support

🚀 Installation

Prerequisites

• Foundry (latest version)
• Node.js and pnpm (for package management)
• Git

Setup

1. Clone the repository

git clone https://github.com/Chitrangath/Agri-Trace.git
cd Agri-Trace

2. Install dependencies

forge install OpenZeppelin/openzeppelin-contracts

3. Verify installation

forge build

🧪 Testing

Run all tests:

forge test

Run tests with verbosity:

forge test -vvv

Run specific test file:

forge test --match-path test/AgricultureSupplyChainTest.t.sol

📦 Deployment

Local Deployment

Deploy to local Anvil node:

# Start Anvil
anvil

# In another terminal, deploy
forge script script/DeployAll.s.sol:DeployAll --rpc-url http://localhost:8545 --broadcast

Sepolia Testnet Deployment

1. Set up environment variables Create a .env file:

PRIVATE_KEY=your_private_key_here
SEPOLIA_RPC_URL=https://sepolia.infura.io/v3/your_key
SEPOLIA_ETHERSCAN_API_KEY=your_etherscan_api_key

2. Deploy to Sepolia

forge script script/DeploySepolia.s.sol:DeploySepolia \
  --rpc-url $SEPOLIA_RPC_URL \
  --broadcast \
  --verify \
  -vvvv

3. Verify contracts on Etherscan The --verify flag will automatically verify contracts. Alternatively:

forge verify-contract <CONTRACT_ADDRESS> <CONTRACT_NAME> \
  --chain sepolia \
  --etherscan-api-key $SEPOLIA_ETHERSCAN_API_KEY

Deployment Addresses

After deployment, addresses are saved to:

• Local: deployments/all-contracts.env
• Sepolia: deployments/sepolia-contracts.env

💻 Usage

For Farmers

1. Register as a farmer (admin only initially):

supplyChain.grantFarmerRole(farmerAddress);
fairPricing.registerFarmer(farmerAddress);

2. Create a product:

uint256 productId = supplyChain.createProduct(
    100,                    // quantity
    500,                    // price (in wei)
    locationHash,           // location hash
    ipfsHashes              // array of IPFS hashes
);

3. Update product stage:

supplyChain.updateProductStage(productId, ProductStage.Harvested);

4. Add quality data:

supplyChain.addQualityData(
    productId,
    25,                     // temperature
    50,                     // humidity
    90,                     // quality score
    certificationHash,      // certification hash
    ipfsHash                // IPFS hash
);

For Distributors/Retailers

1. Get roles:

supplyChain.grantDistributorRole(distributorAddress);
supplyChain.grantRetailerRole(retailerAddress);

2. Transfer ownership:

supplyChain.transferOwnership(productId, newOwner, newPrice);

For Consumers

1. Verify product by ID:

ProductSummary memory summary = consumerInterface.verifyProduct(productId);

2. Verify product by QR code:

VerificationResult memory result = consumerInterface.verifyByQRCode(qrHash);

3. Get farmer reputation:

FarmerReputation memory reputation = consumerInterface.getFarmerReputation(farmerAddress);

For Administrators

1. Configure contracts:

consumerInterface.configureContracts(
    supplyChainAddress,
    qrRegistryAddress,
    fairPricingAddress
);

2. Set minimum prices:

fairPricing.updateGlobalMinimumPrice(1 ether);

3. Manage fraud detection:

fraudDetection.updateDetectionConfig(newConfig);

🔒 Security

Security Features

• ✅ OpenZeppelin contracts (battle-tested)
• ✅ ReentrancyGuard protection
• ✅ Access control with roles
• ✅ Pausable contracts for emergencies
• ✅ Custom errors for gas efficiency
• ✅ Safe transfer functions (Address.sendValue)

Security Considerations

• ⚠️ Price Oracle: Currently uses a simplified implementation. For production, integrate with Chainlink or similar oracle.
• ⚠️ Admin Functions: Consider implementing timelock and multi-sig for production.
• ⚠️ Upgradeability: Contracts are not upgradeable. Consider proxy pattern for production if needed.

Audit Status

⚠️ Not yet audited. This code is for testing purposes. A professional security audit is recommended before mainnet deployment.

📊 Gas Optimization

The contracts are optimized for gas efficiency:

• Packed structs to minimize storage slots
• Custom errors instead of require strings
• Efficient storage patterns
• Calldata usage for arrays

🤝 Contributing

Contributions are welcome! Please:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests
5. Submit a pull request

📝 License

MIT License - see LICENSE file for details

🔗 Links

• Foundry Documentation
• OpenZeppelin Contracts
• Sepolia Testnet Faucet

📧 Contact

For questions or issues, please open an issue on GitHub.

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⚠️ Disclaimer: This is testnet software. Use at your own risk. Not audited for production use.