ethereumjs-tx

What is ethereumjs-tx?

The ethereumjs-tx package is a JavaScript library for creating, signing, and serializing Ethereum transactions. It is part of the ethereumjs suite of tools and is widely used for interacting with the Ethereum blockchain at a low level.

What are ethereumjs-tx's main functionalities?

Creating a Transaction

This feature allows you to create a new Ethereum transaction by specifying parameters such as nonce, gas price, gas limit, recipient address, value, and data.

const Tx = require('ethereumjs-tx').Transaction;
const txParams = {
  nonce: '0x00',
  gasPrice: '0x09184e72a000',
  gasLimit: '0x2710',
  to: '0x0000000000000000000000000000000000000000',
  value: '0x00',
  data: '0x00',
};
const tx = new Tx(txParams);

Signing a Transaction

This feature allows you to sign a transaction using a private key. The transaction must be signed before it can be sent to the Ethereum network.

const privateKey = Buffer.from('your_private_key', 'hex');
tx.sign(privateKey);

Serializing a Transaction

This feature allows you to serialize a signed transaction into a format that can be sent over the network. The serialized transaction is typically represented as a hexadecimal string.

const serializedTx = tx.serialize();
console.log(serializedTx.toString('hex'));

Other packages similar to ethereumjs-tx

web3

Web3.js is a comprehensive library for interacting with the Ethereum blockchain. It provides higher-level abstractions for sending transactions, interacting with smart contracts, and querying blockchain data. Unlike ethereumjs-tx, which focuses on low-level transaction creation and signing, Web3.js offers a broader range of functionalities.

ethers

Ethers.js is a lightweight library for interacting with the Ethereum blockchain. It provides utilities for creating and signing transactions, interacting with smart contracts, and querying blockchain data. Ethers.js is known for its simplicity and ease of use, making it a popular alternative to ethereumjs-tx for developers who prefer a more streamlined API.

eth-lib

Eth-lib is a low-level library for Ethereum that provides utilities for creating and signing transactions, encoding and decoding data, and working with cryptographic primitives. It is similar to ethereumjs-tx in that it focuses on low-level operations, but it also includes additional utilities for working with Ethereum data structures.

README

SYNOPSIS

or #ethereumjs on freenode

INSTALL

npm install ethereumjs-tx

USAGE

• example

const EthereumTx = require('ethereumjs-tx').Transaction
const privateKey = Buffer.from(
  'e331b6d69882b4cb4ea581d88e0b604039a3de5967688d3dcffdd2270c0fd109',
  'hex',
)

const txParams = {
  nonce: '0x00',
  gasPrice: '0x09184e72a000',
  gasLimit: '0x2710',
  to: '0x0000000000000000000000000000000000000000',
  value: '0x00',
  data: '0x7f7465737432000000000000000000000000000000000000000000000000000000600057',
}

// The second parameter is not necessary if these values are used
const tx = new EthereumTx(txParams, { chain: 'mainnet', hardfork: 'petersburg' })
tx.sign(privateKey)
const serializedTx = tx.serialize()

Chain and Hardfork Support

The Transaction and FakeTransaction constructors receives a second parameter that lets you specify the chain and hardfork to be used. By default, mainnet and petersburg will be used.

There are two ways of customizing these. The first one, as shown in the previous section, is by using an object with chain and hardfork names. You can see en example of this in ./examples/ropsten-tx.ts.

The second option is by passing the option common set to an instance of ethereumjs-common' Common. This is specially useful for custom networks or chains/hardforks not yet supported by ethereumjs-common. You can see en example of this in ./examples/custom-chain-tx.ts.

MuirGlacier Support

The MuirGlacier hardfork is supported by the library since the v2.1.2 release.

Istanbul Support

Support for reduced non-zero call data gas prices from the Istanbul hardfork (EIP-2028) has been added to the library along with the v2.1.1 release.

EIP-155 support

EIP-155 replay protection is activated since the spuriousDragon hardfork. To disable it, set the hardfork in the Transaction's constructor.

API

./docs/

EthereumJS

See our organizational documentation for an introduction to EthereumJS as well as information on current standards and best practices.

If you want to join for work or do improvements on the libraries have a look at our contribution guidelines.

LICENSE

MPL-2.0

Changelog

[2.1.2] - 2019-12-19

• Added support for the MuirGlacier HF by updating the ethereumjs-common dependency to v1.5.0