Is there a way to read token address from the command line Hardhat script RSK

Question

I have a Hardhat script that queries the RIF token balance on Rootstock. However the RIF address is hardcoded in my script: ​

const rifTokenAddress = '0x2aCc95758f8b5F583470bA265Eb685a8f45fC9D5';
​
async function main() {
  const erc20 = await ethers.getContractAt(
    ['function balanceOf(address owner) view returns (uint)'],
    rifTokenAddress.toLowerCase(),
  );
  const walletAddress = (await ethers.getSigner(0)).address;
  const rifBalance = await erc20.balanceOf(walletAddress);
  console.log(ethers.utils.formatEther(rifBalance));
}
​
main();

​ Now I am using this command to run the script: ​

npx hardhat run scripts/balances.js --network rskmainnet

​ I would like to be able to specify a token address in the command line like this: ​

npx hardhat run scripts/balances.js --network rskmainnet --token 0x2d919f19D4892381d58EdEbEcA66D5642ceF1A1F

​ Is there a way to modify Hardhat script so that it could read token address from the command line, similar to how I select the network with --network parameter? ​ For reference, this is my hardhat.config.js file: ​

require('@nomicfoundation/hardhat-toolbox');
const { mnemonic } = require('./.secret.json');
​
const accounts = {
  mnemonic,
  path: "m/44'/60'/0'/0",
};
​
module.exports = {
  solidity: '0.8.9',
  networks: {
    hardhat: {},
    rsktestnet: {
      chainId: 31,
      url: 'https://public-node.testnet.rsk.co/',
      accounts,
    },
    rskmainnet: {
      chainId: 30,
      url: 'https://public-node.rsk.co/',
      accounts,
    },
  },
};

Answer 1

One quick solution that I can think of is, put your npx hardhat command as a script in your package.json.

"hardhat-runner": "npx hardhat run --network rskmainnet scripts/balances.js"

Now you can invoke this using the following command. Now pass your arg 'token'.

npm run hardhat-runner --token=0x2d919f19D4892381d58EdEbEcA66D5642ceF1A1F

In your js code, you will get this as env variable.

process.env.npm_config_token

IMO, hardhat does not accept custom args hence passing any args directly will lead to HH308 error. This may change in future though.

Note: This solution has been tested on NPM 7 only.

Cheers.