Contract Loader

Load contract objects from built artifacts or ABIs. Includes support for both web3-eth-contract and @truffle/contract objects.

Overview

Installation

npm install @openzeppelin/contract-loader

You may also need to install web3-eth-contract or @truffle/contract, depending on which abstractions you want to be able to load.

Usage

Create a loader object:

const { setupLoader } = require('@openzeppelin/contract-loader');

const loader = setupLoader({
  provider,        // either a web3 provider or a web3 instance
  defaultSender,   // optional
  defaultGas,      // optional, defaults to 200 thousand
  defaultGasPrice, // optional, defaults to 1 gigawei
});

Load web3 contracts:

const ERC20 = loader.web3.fromArtifact('ERC20');

// Deploy contract
const token = await ERC20.deploy().send();

// Send transactions and query state
const balance = await token.methods.balanceOf(sender).call();
await token.methods.transfer(receiver, balance).send({ from: sender });

Load Truffle contracts:

const ERC20 = loader.truffle.fromArtifact('ERC20');

// Deploy contract
const token = await ERC20.new();

// Send transactions and query state
const balance = await token.balanceOf(sender);
await token.transfer(receiver, balance, { from: sender });

Learn More

  • For detailed usage information, take a look at the API Reference.