A simple library for building Ethereum smart contract interactions. When offline, or away from a web3 wallet, smart contract interaction is quite difficult. This is because it requires special transaction data that defines a function call on a smart contract. This library intends to improve this experience by providing a simple interface for common smart contract function calls. It also aims to be extensible to a wide variety of contracts.
npm i @bitgo/eth-contracts
The basic usage enables users to specify contracts by name and build transaction data from them.
import { Contract } from '@bitgo/eth-contracts';
const cDAI = new Contract('Compound').instance('cDAI');
const { data, amount, address } = cDAI.methods().mint.call({ mintAmount: '1000000000' });
Users can specify an instance of the contract protocol by address instead of name
import { Contract } from '@bitgo/eth-contracts';
const cDAI = new Contract('Compound').address('0x5d3a536e4d6dbd6114cc1ead35777bab948e3643');
const { data, amount, address } = cDAI.methods().mint.call({ mintAmount: '1000000000' });
The output of this library is well formed as an argument to a BitGo SDK sendMany
call. This makes it useful for
integration alongside the Bitgo SDK.
import { Contract } from '@bitgo/eth-contracts';
import { BitGo, Coin } from 'bitgo';
async function sendBitGoTx() {
const bitGo = new BitGo({ env: 'test' });
const baseCoin = bitGo.coin('eth');
const bitGoWallet = await baseCoin.wallets().get({ id: '5941ce2db42fcbc70717e5a898fd1595' });
const cDAI = new Contract('Compound').instance('cDAI');
const transaction = await bitGoWallet.sendMany({
recipients: cDAI.methods().mint.call({ mintAmount: '1000000000' }),
walletPassphrase: 'password'
})
}
sendBitGoTx();
listContractTypes() -- get the available contract types.
const types = Contract.listContractTypes();
// response: ['Compound', 'StandardERC20']
listMethods() -- get the available contract methods.
const types = new Contract('StandardERC20').listMethods();
// response: [{ name: 'transfer', inputs: [...], outputs: [...] }, { name: 'approve', ... }]
methods() -- get contract method builder objects
const types = new Contract('StandardERC20').methods();
// response: { transfer: { call: <function to build transfer> }, approve: { call: <function to build approve> } }
getName() -- get contract name
const types = new Contract('StandardERC20').getName();
// response: StandardERC20
address() -- set contract address
const types = new Contract('StandardERC20').address('0x5d3a536e4d6dbd6114cc1ead35777bab948e3643');
// response: Contract with address set
instance() -- set contract instance
const types = new Contract('StandardERC20').instance('DAI');
// response: Contract with DAI address set
This library supports a limited number of smart contract protocols, as it maintains solidity ABIs locally.
This library is quite extensible to new protocols -- if there are other contract types that you would like to use, feel free to submit a PR adding them. To do so, make the following changes:
- Add the JSON ABI to
abis
directory, named[ProtocolName].json
- Add the ProtocolName and addresses for various instances of the protocol in
config/instances.json
- For example, Compound protocol has cDAI, cUSDC, etc.
- Add the protocol to the README above
- Add some example usages in the
examples
directory