ContentHub

A decentralized content marketplace on Base Sepolia where creators upload encrypted videos and viewers pay with USDC to access them.

Creators register channels, set subscription/rental/purchase prices in USDC, and upload content encrypted via Lighthouse. Viewers pay through the x402 protocol (HTTP 402 challenge-response) to subscribe, rent (24h), or buy (lifetime) access. Only paid viewers can decrypt and watch premium content.

How It Works

1. Creator registers a channel on-chain via the CreatorHub contract
2. Creator uploads content — premium content is encrypted client-side with Lighthouse, free content goes directly to IPFS
3. Viewer requests access — API returns HTTP 402 with USDC payment metadata
4. Viewer pays — frontend approves USDC and calls the contract (subscribe/rent/buy)
5. Viewer proves payment — sends X-PAYMENT: <txHash> header, server verifies on-chain
6. Viewer decrypts — Lighthouse token-gated decryption unlocks the content

All payments use ERC-20 transferFrom (USDC on Base Sepolia). No native ETH payments.

Project Structure

contenthub/
├── contracts/                    # Foundry smart contracts
│   ├── src/CreatorHub.sol        # Main contract (channels, content, payments)
│   ├── test/CreatorHub.t.sol     # 20 tests with MockUSDC
│   └── script/DeployHub.s.sol    # Deployment script
└── frontend/                     # Next.js 15 application
    ├── src/app/
    │   ├── api/x402/             # x402 payment endpoints (subscribe, content)
    │   ├── api/upload/           # Upload routes (key, proxy)
    │   ├── api/content/          # Content authorization
    │   ├── upload/               # Creator upload page
    │   ├── content/[id]/         # Viewer page (pay, decrypt, watch)
    │   ├── creators/[address]/   # Creator profile (subscribe)
    │   ├── dashboard/            # Creator dashboard
    │   └── explore/              # Browse content
    ├── src/hooks/
    │   ├── useX402.ts            # x402 payment hook (approve, call, prove)
    │   └── useSubscription.ts    # Subscription status check
    ├── src/lib/
    │   ├── auth.ts               # Privy auth + wallet ownership verification
    │   ├── lighthouse.ts         # Encrypted upload + token-gated decryption
    │   └── subscription.ts       # On-chain access checks
    └── src/config/
        ├── constants.ts          # Contract address, USDC config, ABI
        └── CreatorHub.json       # Contract ABI

Tech Stack

Layer	Technology
Frontend	Next.js 15, Tailwind CSS v4, Framer Motion
Contracts	Foundry, Solidity ^0.8.30
Payments	x402 protocol, USDC (ERC-20)
Auth	Privy (wallet ownership verification)
Storage	Lighthouse (IPFS, encrypted uploads)
Network	Base Sepolia (Chain ID 84532)

Quick Start

Prerequisites

• Node.js 18+
• Foundry (curl -L https://foundry.paradigm.xyz | bash)
• Wallet with Base Sepolia ETH and USDC

Contracts

cd contracts
forge install
forge test

To deploy:

PRIVATE_KEY=<key> USDC_TOKEN=0x036CbD53842c5426634e7929541eC2318f3dCF7e \
  forge script script/DeployHub.s.sol --rpc-url https://sepolia.base.org --broadcast

Frontend

cd frontend
cp .env.example .env.local  # Configure Privy + Lighthouse keys
npm install
npm run dev

Open http://localhost:3000

Environment Variables

Variable	Description
NEXT_PUBLIC_PRIVY_APP_ID	Privy application ID
PRIVY_APP_SECRET	Privy server-side secret
NEXT_PUBLIC_LIGHTHOUSE_API_KEY	Lighthouse API key for uploads
NEXT_PUBLIC_IPFS_GATEWAY	IPFS gateway URL

Deployed Contracts

Contract	Address (Base Sepolia)
CreatorHub	0xCfd96d36B8A493478903cdCB971052A786E4ff40
USDC (Testnet)	0x036CbD53842c5426634e7929541eC2318f3dCF7e

x402 Payment Flow

Client                          Server                         Chain
  |                                |                              |
  |-- POST /api/x402/content ---->|                              |
  |<-- 402 + USDC metadata -------|                              |
  |                                |                              |
  |-- approve(USDC, amount) ----->|                              |-->
  |-- rentContent(id) ----------->|                              |-->
  |                                |                              |
  |-- POST + X-PAYMENT: txHash -->|                              |
  |                                |-- verify on-chain ---------->|
  |<-- 200 + decryption access ---|                              |

License

MIT