Blockchain Developer Bootcamp Final Project - NFT Lend

URL of deployed application

http://faulty-hill.surge.sh/

You will need some ERC-721 in your account to test this.

Running the project locally

Prerequisites

• yarn should be installed
• npm should be installed
• Node.js >= v14
• Browser with Metamask extension installed

Contracts

After checking out the main branch of this project:

1. yarn install to install dependencies
2. yarn compile to compile smart contracts
3. yarn test to run unit tests

Deploy contracts to local network, and setup test environment

4. Start a new terminal, and run yarn hardhat node
   1. We will make use of the generated account's private keys for testing, so please take note of:
      1. Account 1: Lender of NFT, deployer of contracts
      2. Account 2: Borrower of NFT
5. A local hardhat node should be running, and you'll see: Started HTTP and WebSocket JSON-RPC server at http://127.0.0.1:8545/
6. Leave the terminal running until the end of tests, and use another one for the subsequent steps
7. yarn hardhat run scripts/testing/deploy_w_testtokens.ts --network localhost to
   1. deploy test NFT to local hardhat node
      1. Take note of NFT address printed in console
   2. mint 3 NFTs to account 1
      1. Take note that minted NFTs have token-ids 0, 1, and 2
   3. deploy the lender contract.
      1. Take note of the Lender contract

Start UI locally

8. Use the lender contract address from step 7.3.1 and update the following variables in frontend/src/App.svelte

   const lenderAddress = '<>'; // address from step 7.3.1
   const contractCreationBlock = 0; // set this to 0
   

9. cd frontend
10. npm install to install frontend dependencies
11. npm run build to build the frontend
12. npm run dev to start the frontend, it should be deployed to http://localhost:5000

Screencast link

https://youtu.be/fsz7ex5a-JY

Public Ethereum wallet for certification:

0x8C67b4AAF78CF53b624d8bcB63Ca7513A5634203

Project description

NFT Lend

The application will provide an interface that allows a user (user A) to lend out an NFT to another user (user B) for set period of time (eg. 1 day). The borrower (user B) can freely transfer the temporary ownership (represented by a wrapper NFT). The application will also provide an interface for anyone to check the current owner of a lent NFT. A borrower should be able to return the borrowed NFT by burning the wrapper NFT.

Workflows

Simple lending workflow

Lender

1. Enter website
2. Login with Metamask
3. Enter NFT Token address, token id, and borrower address
4. Click 'Lend'
5. Use the 'verify ownership' form to check that the contract is returning the borrower's address as the virtual owner.

Borrower

1. Enter website
2. Connect with Metamask
3. Observe that the borrowed NFT is showing up under 'borrowed' section.

Collecting an NFT that was borrowed (Not implemented in UI)

Lender

1. After the lending duration has expired, enter the website
2. Connect with Metamask
3. Click on 'Collect' on an NFT under the 'lent' section
4. Use the 'verify ownership' to check that you are the new virtual owner. NFT contract should also say that you are the current owner.

Returning an NFT early (Not implemented in UI)

Borrower

1. Enter the website
2. Connect with Metamask
3. Click on 'Return' to burn the wrapped token and return the lent token to the original owner.

Directory structure

• frontend: Project's React frontend.
• contracts: Smart contracts that are deployed in the Ropsten testnet.
• test: Tests for smart contracts.

Environment variables (not needed for running project locally)

This is only required for deployment

• Make a copy of env.example and name it env. Update it with the below values:
• Etherscan_api_key is not required.
• You need an alchemy account or some other ropsten endpoint
• Private key will be the private key of the account that you'll be using for deployment

ETHERSCAN_API_KEY=
ROPSTEN_URL=https://eth-ropsten.alchemyapi.io/v2/<YOUR ALCHEMY KEY>
PRIVATE_KEY=

TODO features

• UI for returning of NFT
• UI to display status of lent/borrowed NFTs, and to enable filtering
• Use ERC-1155 to track lending instead
• Support for lending out ERC-1155 tokens