Assignment 9 NFT

This project contains two separate NFT contracts for the assignment:

• SoulboundVisitCardERC721.sol - a soulbound ERC-721 student visit card.
• GameCharacterCollectionERC1155.sol - an ERC-1155 collection of 10 game characters.

Contracts

SoulboundVisitCardERC721

• Uses OpenZeppelin ERC721URIStorage and Ownable.
• Owner/admin can mint with mintVisitCard(address student, string tokenUri).
• Each student wallet can receive exactly one visit card.
• Transfers are disabled by overriding transferFrom and safeTransferFrom.
• Approvals are disabled by overriding approve and setApprovalForAll.
• Metadata is stored off-chain and returned through tokenURI.

GameCharacterCollectionERC1155

• Uses OpenZeppelin ERC1155 and Ownable.
• Supports 10 token IDs: 1 through 10.
• Owner/admin can assign metadata with setTokenUri.
• Owner/admin can mint one token or batch mint with mintBatch.
• Standard ERC-1155 transfer, approval, and batch transfer behavior remains enabled.
• Metadata is stored off-chain and returned through uri.

Metadata

Metadata examples are in the metadata directory.

• metadata/visit-card.json contains the ERC-721 visit card metadata with image and attributes such as studentName, studentID, course, and year.
• metadata/character-1.json through metadata/character-10.json contain ERC-1155 marketplace-compatible metadata. Each file has a unique image URI and attributes such as color, speed, strength, and rarity.

The current metadata files use public HTTPS image URLs for a quick classroom/demo setup. The mint script points token metadata to the raw GitHub URLs under metadata/, so the JSON files become reachable after this repository is pushed. If strict IPFS hosting is required, upload the images and JSON metadata to IPFS and replace the metadata/image values with ipfs://... links.

Setup

Install dependencies:

npm install

Compile:

npm run compile

Run tests:

npm test

On Windows PowerShell, if npx is blocked by execution policy, use:

npx.cmd hardhat test

Environment

Create a .env file:

SEPOLIA_RPC_URL=https://sepolia.infura.io/v3/YOUR_KEY
PRIVATE_KEY=YOUR_PRIVATE_KEY

Do not commit .env.

Deployment

Deploy both contracts:

npx hardhat run scripts/deploy.js --network sepolia

Deploy only the ERC-1155 contract:

npx hardhat run scripts/deploy-erc1155.js --network sepolia

After deployment, update the contract addresses in:

• scripts/mint.js
• scripts/batch-transfer.js

Minting

Run:

npx hardhat run scripts/mint.js --network sepolia

The script:

• Mints one soulbound ERC-721 visit card to the student wallet.
• Sets metadata URIs for all 10 ERC-1155 character IDs.
• Batch mints 10 ERC-1155 NFTs to the owner wallet.
• Batch transfers token IDs 1 and 2 to the student wallet.
• Prints transaction hashes for the ERC-721 mint, ERC-1155 URI updates, ERC-1155 batch mint, and ERC-1155 batch transfer.

To use a specific student wallet, set STUDENT_WALLET in scripts/mint.js.

Batch Transfer Demo

Run:

npx hardhat run scripts/batch-transfer.js --network sepolia

This demonstrates ERC-1155 batch transfer efficiency by transferring token IDs 1 and 2 in a single transaction.

Proof Of Functionality

Add the actual deployed transaction hashes or screenshots after running the scripts on Sepolia:

• ERC-721 visit card mint transaction:
• ERC-1155 batch mint transaction:
• ERC-1155 batch transfer transaction:
• Screenshot/link showing student wallet owns one soulbound visit card:
• Screenshot/link showing student wallet received 1 or 2 ERC-1155 game characters:

Local proof from tests:

npx.cmd hardhat test
8 passing