LabEval — Blockchain-based Lab Assignment Assessment Platform

A decentralized application (dApp) for lab assignment assessment built on Ethereum blockchain with AI-powered grading and IPFS storage.

Quick Start

cd lab_eval_blockchain/ChainAssess
cp .env.example .env   # fill in your API keys
npm install
npm run dev

See lab_eval_blockchain/ChainAssess/README.md for full documentation.

📖 Overview

LabEval is a comprehensive blockchain-based platform that revolutionizes lab assignment assessment by combining:

• Decentralized Storage via IPFS (Pinata)
• Smart Contract automation on Ethereum
• AI-Powered Grading using Google Gemini

✨ Key Features

🔐 Secure & Transparent

• Wallet-based authentication via MetaMask
• All transactions recorded on Ethereum Sepolia testnet
• Role-based access control (Admin, Teacher, Student)
• Immutable grade records on blockchain

🤖 AI-Powered Intelligence

• Automatic grading suggestions using Google Gemini AI
• Multi-format document support (PDF, DOCX, TXT)
• Intelligent text extraction and analysis
• Customizable grading criteria

📚 Complete Assignment Management

• Batch/class management system
• Assignment creation and distribution
• Student submission tracking
• IPFS-based file storage

⚡ User-Friendly

• No student registration required
• Teachers can add students directly by wallet address
• Clean, modern UI built with React and TailwindCSS
• Real-time blockchain transaction updates

🚀 Quick Start

Prerequisites

• Node.js 18 or higher
• MetaMask browser extension
• Sepolia ETH for gas fees (Get free testnet ETH)

Installation

# Clone the repository
git clone https://github.com/nishant-uxs/labeval.git
cd labeval/lab_eval_blockchain/ChainAssess

# Install dependencies
npm install

# Setup environment variables
cp .env.example .env
# Edit .env and add your API keys

# Run the application
npm run dev

The app will be available at http://localhost:5000

Environment Variables

Create a .env file in the ChainAssess directory:

# Blockchain Configuration
ALCHEMY_API_KEY=your_alchemy_api_key_here
PRIVATE_KEY=your_wallet_private_key_here

# IPFS Storage (Pinata)
PINATA_API_KEY=your_pinata_api_key_here
PINATA_SECRET_KEY=your_pinata_secret_key_here

# AI Grading (Optional but recommended)
GEMINI_API_KEY=your_google_gemini_api_key_here

Getting API Keys:

• Alchemy: Sign up at Alchemy and create a Sepolia app
• Pinata: Get API keys from Pinata
• Gemini: Get API key from Google AI Studio

🏗️ Technology Stack

Frontend

• React 19 with TypeScript
• Vite for fast builds
• TailwindCSS + shadcn/ui for styling
• MetaMask SDK for wallet integration
• ethers.js v6 for blockchain interaction

Backend

• Express.js with TypeScript
• Google Gemini AI for grading
• Pinata SDK for IPFS storage
• PDF/DOCX/TXT parsers for document processing

Blockchain

• Ethereum Sepolia Testnet
• Solidity smart contracts
• OpenZeppelin libraries
• Hardhat development environment

Smart Contracts (Already Deployed)

Contract	Address	Purpose
AccessControl	0xFB7c09E0d25577401cB98C9b29B0465243A97E5F	Role management
BatchManagement	0xddD637Fd04a8b14470Bcf3b78c683c1a87C99aB8	Student batches
AssignmentSubmission	0xf39A62a69222ad7F51217AFedd46178e7926039d	Assignment lifecycle

📋 How It Works

For Teachers

1. Connect Wallet → Connect MetaMask (must have AUTHORITY_ROLE)
2. Create Batch → Set up a new class/batch
3. Add Students → Add student wallet addresses (no registration needed!)
4. Create Assignment → Upload assignment files to IPFS
5. Review Submissions → View submissions with AI grading suggestions
6. Award Grades → Accept AI suggestions or provide custom grades

For Students

1. Connect Wallet → Connect MetaMask wallet
2. View Assignments → See assignments from enrolled batches
3. Submit Work → Upload submission files to IPFS
4. Track Progress → View grades on blockchain

📁 Project Structure

labeval/
└── lab_eval_blockchain/
    └── ChainAssess/
        ├── client/              # React frontend
        │   ├── src/
        │   │   ├── components/  # UI components
        │   │   ├── hooks/       # Custom React hooks
        │   │   ├── lib/         # Contract configs
        │   │   └── pages/       # Application pages
        ├── server/              # Express backend
        │   ├── index.ts         # Server entry
        │   ├── blockchain-service.ts
        │   ├── ipfs-service.ts
        │   └── ai-grading-service.ts
        ├── contracts/           # Solidity contracts
        │   ├── AccessControl.sol
        │   ├── BatchManagement.sol
        │   ├── AssignmentSubmission.sol
        ├── scripts/             # Deployment scripts
        ├── package.json
        └── README.md            # Detailed documentation

🔐 Security Features

• ✅ Environment Variables - All sensitive data in .env
• ✅ Role-Based Access - Smart contract enforced permissions
• ✅ MetaMask Signing - All transactions require user approval
• ✅ Input Validation - Server-side and client-side validation
• ✅ IPFS Immutability - Files cannot be modified after upload

🌐 Live Demo & Resources

• Sepolia Etherscan: View Contracts
• Sepolia Faucet: Get Test ETH
• Alchemy Dashboard: Manage API
• Pinata Dashboard: Manage IPFS

🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

👨‍💻 Authors

Nishant

• GitHub: @nishant-uxs

Adarsh

• GitHub: @adrshagr

🙏 Acknowledgments

• OpenZeppelin for secure smart contract libraries
• Ethereum Foundation for blockchain infrastructure
• Google for Gemini AI API
• Pinata for IPFS infrastructure
• Alchemy for blockchain node services

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Built with ❤️ using Ethereum, React, AI, and IPFS

Making contract assessment transparent, secure, and intelligent.