A collection of useful scripts for interacting with EVM compatible blockchains from the command line

• Environment Variable Management
  • Usage
• Hardhat Guide
  • Scripts
  • Tasks
• Script Glossary
  • swap
  • get-price
  • get-abi

This repository uses the NPM package @chainlink/env-enc to keep private keys, RPC URLs, and other secrets encrypted at rest. This helps reduce the risk of leaking your private key.

By default, the @chainlink/env-enc package will store your encrypted environment variables in a file named .env.enc in the root directory of this repository. Ensure that your .gitignore file includes.env.enc

Set the encryption password by running the command

npx env-enc set-pw

Set a new environment variable by running the command

npx env-enc set

See all your currently set environment variables

npx env-enc view

Remove an environment variable

npx env-enc remove SOME_ENV_VAR_NAME

• hardhat.config.ts specifies the settings like imports, networks, solidity verions, etc that will all be made available through the hre (hardhat runtime environment)

• all scripts and tasks are by default executed on the local hardhat network, but can be configured to run on other networks by passing the --network flag .i.e. yarn hardhat NAME_OF_TASK --network arbitrum

• good for executing code that doesnt require parameters

yarn hardhat run scripts/PATH_TO_SCRIPT.ts

• good for executing scripts that require parameters passed on the command line
• to see all availalble tasks run yarn hardhat
• to see which flags you need to pass run yarn hardhat NAME_OF_TASK --help
• not allowed to import hre into scripts that are imported and used by tasks

yarn hardhat NAME_OF_TASK --NAME_OF_FLAG VALUE_OF_FLAG

Swap tokens using uniswap's smart order router that computes the optimal route before executing the swap.

Execute a swap on the local hardhat network that is configured as fork of arbitrum

yarn hardhat swap --in USDC --amount 100 --out rETH

Fetches abi from etherscan API and outputs the result to a .json file inside the ./abis directory

yarn hardhat get-abi --contract 0x514910771AF9Ca656af840dff83E8264EcF986CA --file-name link-token-abi --network mainnet

Gets the price for a base asset in terms of a quote asset using chainlink price feeds

Fetch the price of ETH in USD on mainnet

yarn hardhat get-price --contract 0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419 --network mainnet