Develop an NFT contract by using hardhat and ethers.js. For fullstack dApp development, you can checkout the UI project enftapp that implements a React UI to interact with this sample NFT contract.

The contract is deployed on Rinkeby test net, and can be viewed on etherscan. Tokens are also listed in marketplace, e.g., opensea.

Following instruction in https://github.com/nvm-sh/nvm to install nvm.

Verify nvm installation and then install latest version of node.

nvm -v
nvm install node

Initialize enft project:

mkdir enft
cd enft
npm init

Initialize hardhat configuration:

npm install --save-dev hardhat
npx hardhat (select create an empty hardhat.config.js)
mkdir contracts scripts metadata

We use infura, MetaMask and etherscan to deploy, view and test the contract. So, create a free account on each of the sites.

Create .env file at the root of the project and specify the following parameters.

API_URL="https://rinkeby.infura.io/v3/<infura projectId for rinkeby test net>"
PRIVATE_KEY="<private key from metamask account details>"
PUBLIC_KEY="<metamask account address>"
ETHERSCAN_API_KEY="<etherscan app key"
ENFT_ADDRESS="<contract address returned by deploying the sample contract>"

Create and edit contract ENFT.sol.

cd contracts
touch ENFT.sol  (edit ENFT.sol here)
cd ..
npm install @openzeppelin/[email protected]
npm install dotenv --save
npm install --save-dev @nomiclabs/hardhat-ethers 'ethers@^5.0.0'

Update hardhat.config.js.

Compile the contract:

npx hardhat compile

Create and edit script deploy.js.

cd scripts
touch deploy.js  (edit deploy.js here)
cd ..
npx hardhat run scripts/deploy.js --network rinkeby

Script prints out the contract address, e.g.,

Contract deployed to address: 0xc98e641bBbFab95BD118dA10C4D26Cdc3F1bd387
Transaction hash: 0x2e2978ae013097cb357040d9923a53a295b3923bc4c3ad2cfea9a3ed3697311c

Verify the contract on etherscan:

npm install --save-dev @nomiclabs/hardhat-etherscan
npx hardhat verify --network rinkeby 0xc98e641bBbFab95BD118dA10C4D26Cdc3F1bd387

Upload token images to IPFS:

curl -X POST -F "file=@metadata/flogo.png" https://ipfs.infura.io:5001/api/v0/add

It prints out the resulting hash of the image flogo.png:

{"Name":"flogo.png","Hash":"QmV5F12oxAq3ki2Pz4zF2wo4Cn3HoZzGL5r8hDoKLLEFDr","Size":"3667"}

curl -X POST -F "file=@metadata/tibcolab.png" https://ipfs.infura.io:5001/api/v0/add

It prints out the resulting hash of the image tibcolab.png:

{"Name":"tibcolab.png","Hash":"QmUKpXTahUTHMt651HHe4RqsorUrukKuVTU5RMzFkzFp5p","Size":"5311"}

Verify the content of the uploaded images in IPFS:

curl -X POST "https://ipfs.infura.io:5001/api/v0/cat?arg=QmV5F12oxAq3ki2Pz4zF2wo4Cn3HoZzGL5r8hDoKLLEFDr" > tmp.png
curl -X POST "https://ipfs.infura.io:5001/api/v0/cat?arg=QmUKpXTahUTHMt651HHe4RqsorUrukKuVTU5RMzFkzFp5p" > tmp.png

Create and edit token metadata file flogo.json and tibcolab.json, which contain references to the uploaded images.

Upload metadata files to IPFS:

curl -X POST -F "file=@metadata/flogo.json" https://ipfs.infura.io:5001/api/v0/add

It prints out the hash for flogo.json.

{"Name":"flogo.json","Hash":"QmUqfxdhwktSbuz8kc8rVmWDPP6xUgrwaBAEd3KrKtxfkZ","Size":"387"}

curl -X POST -F "file=@metadata/tibcolab.json" https://ipfs.infura.io:5001/api/v0/add

It prints out the hash for tibcolab.json.

{"Name":"tibcolab.json","Hash":"Qme3QJ9H43kVDDRNrVtbJXo5uUuzqWY2JJyfkqfEHRozf6","Size":"336"}

Create and edit script mint.js, then execute the script to mint some tokens on the Rinkeby testnet.

cd scripts
touch mint.js  (edit mint.js here)
cd ..
npx hardhat run scripts/mint.js --network rinkeby

This script creates 2 tokens. View them on etherscan https://rinkeby.etherscan.io/address/0xc98e641bbbfab95bd118da10c4d26cdc3f1bd387#code, and/or opensea https://testnets.opensea.io/collection/enft.