Using eth-gas-reporter

A good smart contract is the one which is gas-optimized and not-vulnerable to attacks.
And there are some tools which help us analyze these aspects before deploying contract to production.
(I have made a series of blogs on Gas Optimization techniques and Security Vulnerabilities if you are interested)

In this blog, we will see how to use eth-gas-provider to get report of gas-consumption and gas-price for deployment and function calls of the contract.
If reading bores you, head over to my GitHub repo and follow along the steps.

So let's begin:

• Install hardhat if you haven't done already:

npm install --save-dev hardhat

• Create a sample hardhat project:

npx hardhat

This will create a Greeter.sol in contracts directory along with some other files and directories.

• Installing dependencies:

npm i hardhat-gas-reporter

npm i dotenv

• create a .env file(in main directory) as follows:

coinMarketCap_API= //get your api-key at https://coinmarketcap.com/api/pricing/
REPORT_GAS= true // set to false when you don't want gas-report

• Now goto hardhat.config.js file, and replace the content in it with the following:

require("@nomiclabs/hardhat-waffle");
require("hardhat-gas-reporter");
const dotenv = require("dotenv");
dotenv.config();

module.exports = {
  solidity: "0.8.4",
  gasReporter: {
    enabled: (process.env.REPORT_GAS) ? true : false, // will give report if REPORT_GAS environment variable is true
    currency: 'USD', // can be set to ETH and other currencies (see coinmarketcap api documentation)
    coinmarketcap: process.env.coinMarketCap_API // to fetch prices from coinmarketcap api
  }
};

• And finally, use the following command to compile, test, and get gas-report for the sample contract:

npx hardhat test

Output:

You can expect a similar output as follows:

The usd (avg) might vary, based on price of ETH and current gas price. The Avg shows the gas consumption for function call and contract deployment.