ABI Coder

A set of high-level ABI encoding and decoding utils.

Motivation

There are several packages that provide ABI coding utils. However, there is no a high-level solution in the Ethers ecosystem. web3-eth-abi and abi-decoder depend on web3.js. @ethersproject/abi is pretty low-level. ethereumjs-abi works only with functions. Many other packages provide encoding or decoding only.

Features

- Function coding
- Event coding
- Constructor coding
- TS support

Installation

npm install abi-coder

> This package requires ethers V6. If you use ethers V5, you need to install abi-coder V4.

> This package is a pure ESM package. Follow this guide for more info.

Example

``ts
import { Coder } from 'abi-coder';

import * as erc20Abi from './abi/erc20.json';

const erc20Coder = new Coder(erc20Abi);

erc20Coder.getFunctionSelector('totalSupply');
// 0x18160ddd

erc20Coder.decodeEvent(
[
'0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef',
'0x000000000000000000000000b5cfcb4d4745cbbd252945856e1b6eaadcf2fc4e',
'0x000000000000000000000000694c6aea9444876d4fa9375fc9089c370f8e9eda',
],
'0x0000000000000000000000000000000000000000000000370c9b5ef669c35300',
);
/*
{
name: 'Transfer',
inputs: [...],
values: [
'0xb5CFcb4D4745cBBD252945856E1B6eaadCf2fC4E',
'0x694c6aea9444876d4fA9375fC9089C370F8E9edA',
BigNumber('1015479348216300000000'),
],
}
*/

erc20Coder.encodeFunction({
name: 'transfer',
inputs: [
{
name: 'from',
type: 'address',
},
{
name: 'amount',
type: 'uint256',
},
],
values: [
'0x694c6aea9444876d4fA9375fC9089C370F8E9edA',
'1015479348216300000000',
],
});
// '0xa9059cbb000000000000000000000000694c6aea9444876d4fa9375fc9089c370f8e9eda0000000000000000000000000000000000000000000000370c9b5ef669c35300'
``

API

- Coder(abi)
- utils
- getFunctionSelector(name: string): string
- getEventTopic(name: string): string
- decoding
- decodeConstructor(data: string): Constructor
- decodeEvent(topics: string[], data: string): Event
- decodeFunction(data: string): FunctionData
- decodeFunctionOutput(name: string, data: string): FunctionOutputData
- encoding
- encodeConstructor(constructorData: Constructor): string
- encodeEvent(eventData: Event): EventEncoding
- encodeFunction(functionData: FunctionData): string
- encodeFunctionOutput(functionData: FunctionOutputData): string