URLx402 - Blockchain URL Shortener

A decentralized URL shortener powered by x402 micropayments and blockchain storage on Base Sepolia.

✨ Features

• 🔗 URL Shortening - Pay $0.001 USDC to create shortened URLs
• 🔍 URL Lookup - Free blockchain-based URL retrieval
• 💳 x402 Payments - Seamless crypto micropayments via MetaMask
• ⛓️ On-Chain Storage - Permanent URLs stored on Base Sepolia

🚀 Quick Start

Prerequisites

• Node.js 18+ and pnpm
• MetaMask with Base Sepolia network
• Base Sepolia USDC for payments
• Base Sepolia ETH for gas fees

Installation

# Install dependencies
pnpm install

# Copy environment template
cp env.template .env.local

Configuration

Edit .env.local:

# Your deployed contract address on Base Sepolia
NEXT_PUBLIC_CONTRACT_ADDRESS=0xYourContractAddress

# Base Sepolia RPC URL
NEXT_PUBLIC_BASE_SEPOLIA_RPC_URL=https://sepolia.base.org

# Server wallet private key (for contract interaction)
SERVER_PRIVATE_KEY=0xYourPrivateKey

# Payment receiver address (must be NEXT_PUBLIC_ for middleware)
NEXT_PUBLIC_X402_PAYMENT_ADDRESS=0xYourPaymentAddress

# App configuration
NEXT_PUBLIC_APP_URL=http://localhost:3000
NEXT_PUBLIC_CHAIN_ID=84532

Deploy Smart Contract

1. Open Remix IDE
2. Upload contracts/URLStorage_x402.sol
3. Compile with Solidity 0.8.24
4. Deploy to Base Sepolia testnet
5. Authorize your server wallet:

   setServerAuthorization(yourServerAddress, true)
   

Run Development Server

pnpm dev

Open http://localhost:3000

🎯 How It Works

Shorten URL (Paid)

1. Connect your MetaMask wallet
2. Enter a URL to shorten
3. Approve $0.001 USDC payment
4. Get your shortened URL instantly

Lookup URL (Free)

1. Enter any short code
2. Retrieve original URL from blockchain
3. View creator and creation date

💰 Pricing

📚 Resources

• x402 Documentation
• Base Sepolia Explorer
• x402 GitHub

🤝 Contributing

Contributions are welcome! This is a testnet project demonstrating x402 micropayment capabilities.

🙏 Acknowledgments

Built with x402 Protocol by Coinbase for seamless HTTP 402 payments.

Note: This is a testnet application. All transactions use test tokens with no real value.