Use Chainlink Data Feed in Js file without hard coding Data feed Contract's ABI

[GarvitKarnwal]

Hi
Using Chainlink Data Feeds in Javascript is pretty simple. It's given here but the issue with the code is 'Hard coding of ABI'. If we use Hardhat, and create and deploy a smart contract that uses a chain link data feed we don't have to Hard code ABI anywhere. So I am wondering if it is possible to use Chainlink data feed in a Js file but without hard coding the ABI and using Hardhat to do so.

[krakxn]

If you are worried about the explicitly hard-coded ABI, then you can put it in a .env.

If you think the above is too static, you can setup a conditional to account for which data feed's ABI (you can set up the various ones in a .env) to use--this one is more dynamic.

With the above approaches, you can avoid both the hard-coded and the static part of the problem you outlined.

[GarvitKarnwal]

I am still working on this problem. I got as far as the below code:

but I am running into the below shown error:

[alymurtazamemon]

@GarvitKarnwal Please use code instead of pictures so we can copy/paste to point out the issues.

And let me know where did you get this ABI .json file path?

Because the actual interface address is this

import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";

[GarvitKarnwal]

The ABI JSON can be found in the abi folder instead of the src folder.

[GarvitKarnwal]

I got one working code as shown below:

const 
  aggregatorV3InterfaceABI
= require("@chainlink/contracts/abi/v0.8/AggregatorV3Interface.json");
const { ethers } = require("ethers") //ethers.js

async function main() {
    const provider = new ethers.providers.JsonRpcProvider("https://rpc.ankr.com/eth_goerli")
    const addr = "0xA39434A63A52E749F02807ae27335515BA4b07F7"
    const priceFeed = new ethers.Contract(addr, aggregatorV3InterfaceABI, provider)
    let {answer} = await priceFeed.latestRoundData()
    console.log(answer.toString())
}
main()
  .then(() => {
    process.exit(0);
  })
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

OUTPUT:

[alymurtazamemon]

@GarvitKarnwal Try this line const priceFeed = new ethers.Contract(addr, aggregatorV3InterfaceABI, provider) instead of getContractAt function in your code and let me know the result.

[GarvitKarnwal]

One more thing I noticed today. We don't need hardhat to run the above code. you can simply run the code using cmd: node scripts/getDataFeed.js
Just need to install @chainlink/contracts and use the ABI.

[alymurtazamemon]

@GarvitKarnwal Yes