Here is an example of an NFT contract written in Solidity that stores image metadata and the image file itself on IPFS:
pragma solidity ^0.5.0;
import "https://github.com/ipfs/js-ipfs-http-client/blob/master/src/index.js";
import "https://github.com/ipfs/js-ipfs-api/blob/master/src/index.js";
contract NFT {
string public name;
string public symbol;
uint8 public decimals;
uint256 public totalSupply;
mapping(uint256 => Image) public images;
mapping(address => uint256) public balanceOf;
struct Image {
string ipfsHash;
string metadata;
}
constructor(string memory _name, string memory _symbol, uint8 _decimals, uint256 _totalSupply) public {
name = _name;
symbol = _symbol;
decimals = _decimals;
totalSupply = _totalSupply;
}
function addImage(string memory _ipfsHash, string memory _metadata) public {
require(balanceOf[msg.sender] < totalSupply, "You have reached the maximum number of images you can add.");
uint256 id = balanceOf[msg.sender];
images[id] = Image(_ipfsHash, _metadata);
balanceOf[msg.sender]++;
}
function getImage(uint256 _id) public view returns (string memory, string memory) {
Image storage image = images[_id];
return (image.ipfsHash, image.metadata);
}
}
This contract has a totalSupply parameter that limits the number of images that can be added to the contract. The addImage function is called to add a new image to the contract and store its IPFS hash and metadata. The getImage function can be called to retrieve the IPFS hash and metadata for a specific image.
To connect to IPFS and add an image, you will need to use a library like js-ipfs-api or js-ipfs-http-client. Here is an example of how you might use js-ipfs-api in a JavaScript file to add an image to IPFS and then add the image to the contract:
const IPFS = require('ipfs-api');
const ipfs = new IPFS({ host: 'ipfs.infura.io', port: 5001,