ethers

What is ethers?

The ethers npm package is a library that provides a set of tools to interact with the Ethereum blockchain. It allows users to connect to the Ethereum network, manage wallets and keys, interact with smart contracts, and perform various other blockchain-related operations.

What are ethers's main functionalities?

Connecting to Ethereum Network

This code sample demonstrates how to connect to the Ethereum network using ethers with an Infura provider.

const { ethers } = require('ethers');
const provider = new ethers.providers.JsonRpcProvider('https://mainnet.infura.io/v3/YOUR_INFURA_API_KEY');

Wallet Management

This code sample shows how to create a new wallet from a private key and connect it to an Ethereum provider.

const { ethers } = require('ethers');
const wallet = new ethers.Wallet('YOUR_PRIVATE_KEY');
const connectedWallet = wallet.connect(provider);

Interacting with Smart Contracts

This code sample illustrates how to interact with a smart contract by creating a contract instance and calling one of its functions.

const { ethers } = require('ethers');
const abi = [...] // Contract ABI
const contractAddress = '0x...'; // Contract address
const contract = new ethers.Contract(contractAddress, abi, provider);
const value = await contract.someFunction();

Sending Transactions

This code sample demonstrates how to send a transaction to the Ethereum network using a wallet instance.

const { ethers } = require('ethers');
const tx = {
  to: '0x...',
  value: ethers.utils.parseEther('1.0'),
  gasLimit: 21000,
  gasPrice: ethers.utils.parseUnits('10', 'gwei')
};
const sendPromise = wallet.sendTransaction(tx);

Querying Blockchain Data

This code sample shows how to query blockchain data, such as retrieving the latest block number and details of a specific block.

const { ethers } = require('ethers');
const blockNumber = await provider.getBlockNumber();
const block = await provider.getBlock(blockNumber);

Other packages similar to ethers

truffle-contract

Truffle Contract is part of the Truffle Suite and is designed to provide a more comfortable abstraction for interacting with Ethereum smart contracts. It is often used in combination with other Truffle tools for development, testing, and deployment. While it offers similar contract interaction capabilities, it is more tightly integrated with the Truffle development environment compared to ethers.

drizzle

Drizzle is a collection of front-end libraries that make writing dApp front-ends easier and more predictable. It is part of the Truffle Suite and is designed to work with a Redux store. Drizzle provides reactive contract data fetching and transaction processing, which can be more convenient for dApp development. However, it is more opinionated and specific to front-end development compared to ethers, which is more general-purpose.

README

ethers.js

Complete Ethereum wallet implementation and utilities in JavaScript (and TypeScript).

Features:

• Keep your private keys in your client, safe and sound
• Import and export JSON wallets (Geth, Parity and crowdsale)
• Import and export BIP 39 mnemonic phrases (12 word backup phrases) and HD Wallets (English, French, Italian, Japanese, Korean, Simplified Chinese, Spanish, Traditional Chinese)
• Meta-classes create JavaScript objects from any contract ABI, including ABIv2 and Human-Readable ABI
• Connect to Ethereum nodes over JSON-RPC, INFURA, Etherscan, or MetaMask
• ENS names are first-class citizens; they can be used anywhere an Ethereum addresses can be used
• Tiny (~84kb compressed; 270kb uncompressed)
• Complete functionality for all your Ethereum needs
• Extensive documentation
• Large collection of test cases which are maintained and added to
• Fully TypeScript ready, with definition files and full TypeScript source
• MIT License (including ALL dependencies); completely open source to do with as you please

Keep Updated

For the latest news and advisories, please follow @ethersproject on Twitter as well as this GitHub project.

Installing

To use in a browser:

<script charset="utf-8"
        src="https://cdn.ethers.io/scripts/ethers-v4.min.js"
        type="text/javascript">
</script>

To use in node.js:

/Users/ethers/my-app> npm install --save ethers

Documentation

Browse the API Documentation online.

To fork and submit pull requests to the documentation, please see the documentation repository.

Related Libraries

• Command Line Interface - Command Line Tools for ethers
• CryptoKitties - CryptoKitties utility libraries
• ENS - ENS utility libraries for managing names
• LedgerSigner - Use a Ledger Hardware Wallet as an ethers Signer (supports HID (node.js) and U2F (browser); or specify your own transport)
• Web3 Bridge - Use ethers as the backend for a Web3 front-end

Hacking and Contributing

The JavaScript code is now generated from TypeScript, so make sure you modify the TypeScript and compile it, rather than modifying the JavaScript directly. To start auto-compiling the TypeScript code, you may use:

/home/ethers> npm run auto-build

A very important part of ethers is its exhaustive test cases, so before making any bug fix, please add a test case that fails prior to the fix, and succeeds after the fix. All regression tests must pass.

Pull requests are always welcome, but please keep a few points in mind:

• Compatibility-breaking changes will not be accepted; they may be considered for the next major version
• Security is important; adding dependencies require fairly convincing arguments
• The library aims to be lean, so keep an eye on the dist/ethers.min.js file size before and after your changes
• Add test cases for both expected and unexpected input
• Any new features need to be supported by us (issues, documentation, testing), so anything that is overly complicated or specific may not be accepted

In general, please start an issue before beginning a pull request, so we can have a public discussion. :)

Donations

I do this because I love it, but if you want to buy me a coffee, I won't say no. :o)

Ethereum: 0xEA517D5a070e6705Cc5467858681Ed953d285Eb9

License

Completely MIT Licensed. Including ALL dependencies.