Mini-Mart: A Lightweight ERC721 Marketplace

Mini-Mart is a gas-efficient, signature-based (EIP-712) ERC721 marketplace contract built with the Foundry framework. It allows users to list NFTs for sale with off-chain signatures, minimizing gas costs for sellers. The marketplace logic is executed on-chain only during the fulfillment of an order.

Core Features

• On-Chain Order Fulfillment: A buyer fills the seller's signed order to the contract, and the fulfillOrder function atomically handles payment, fee collection, and NFT transfer.
• Buyer Protection: If an order cannot be fulfilled (e.g., the NFT was transferred, approval was revoked, or the listing expired), the buyer's payment is automatically refunded within the same transaction.
• Fixed Platform Fee: A 3% fee is collected on every successful sale.
• Admin Controls:
  • Pausable: The owner can pause and unpause all trading activity (addOrder, fulfillOrder) in case of an emergency.
  • Fee Withdrawal: The owner can withdraw all accumulated fees from the contract.
• Comprehensive Testing: The project includes an extensive test suite using Foundry, covering unit tests, negative paths, and fuzz testing.

Getting Started

Prerequisites

• Foundry: You will need forge and anvil installed.
• Slither: For static analysis.
• Mythril: For symbolic execution analysis.

Installation & Setup

1. Clone the repository:

   git clone https://github.com/your-username/mini-mart.git
   cd mini-mart

2. Install dependencies:

   forge install

3. Set up environment variables: Create a .env file in the root of the project. This file is required for deploying to live networks and verifying contracts on Etherscan.

   # .env
   # For live network deployments (e.g., 'make deploy')
   RPC_URL=https://your_rpc_provider_url
   WALLET_ID=your_keystore_wallet_alias # e.g., my_wallet.json
   KEYSTORE_PASSWORD=your_keystore_password
   
   # For Etherscan verification
   ETHERSCAN_API_KEY=your_etherscan_api_key

Deployment

The deployment commands require a script file from the script/ directory to be passed as an argument.

• Deploy to a Local Network (Anvil): This command uses the DeployLocal.s.sol script, which not only deploys the contracts but also seeds the local environment by whitelisting the test NFT, minting tokens, and creating/removing sample orders.

  1. Start a local Anvil node in a separate terminal:

     anvil

  2. Run the local deployment script:

     make deploy-local DeployLocal.s.sol

• Deploy to a Live Network: This requires RPC_URL, WALLET_ID, and KEYSTORE_PASSWORD to be set in your .env file. The Deploy.s.sol script is a template and must be filled out before use.

  # Example: Dry-run a deployment without broadcasting the transaction
  make dry-run Deploy.s.sol
  
  # Example: Execute the deployment and broadcast the transaction
  make deploy Deploy.s.sol

Contract Overview

MiniMart.sol

This is the core contract. It implements the EIP-712 standard to create verifiable off-chain order data.

Order Flow:

1. Seller: Creates an Order struct with sale details (price, tokenId, etc.) and signs its EIP-712 hash.
2. Buyer: Submits the Order struct and the seller's signature to the addOrder() function. The contract verifies the signature and lists the order.
3. Buyer: Calls fulfillOrder() with the correct msg.value to purchase the NFT. The contract verifies all conditions (e.g., ownership, approval), transfers the NFT to the buyer, and pays the seller (minus fees).