KardiaChain Docs

Deploy KRC721 tokens

  • Connect your MetaMask wallet to KardiaChain mainnet or testnet. Detail instruction can be found here.
  • Have some KAI in your wallet to use as transaction fee
Deploying a new KRC721 token can be done by using Remix and ERC721 contract from Open Zeppelin open source.
  1. 2.
    Create new contract KRC721.sol and copy code from the following sample
// contracts/GameItem.sol
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721URIStorage.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
contract GameItem is ERC721URIStorage {
using Counters for Counters.Counter;
Counters.Counter private _tokenIds;
constructor() ERC721("GameItem", "ITM") {}
function awardItem(address player, string memory tokenURI)
returns (uint256)
uint256 newItemId = _tokenIds.current();
_mint(player, newItemId);
_setTokenURI(newItemId, tokenURI);
return newItemId;
3. Deploy contract
Deploy KRC721 contract
Deploy successfully
After deployed, new items can be created:
> gameItem.awardItem(playerAddress, "https://game.example/item-id-8u5h2m.json")
Transaction successful. Transaction hash: 0x...
Events emitted:
- Transfer(0x0000000000000000000000000000000000000000, playerAddress, 7)
And the owner and metadata of each item queried:
> gameItem.ownerOf(7)
> gameItem.tokenURI(7)
This tokenURI should resolve to a JSON document that might look something like:
"name": "Thor's hammer",
"description": "Mjölnir, the legendary hammer of the Norse god of thunder.",
"image": "https://game.example/item-id-8u5h2m.png",
"strength": 20