Rollux Docs

ethers.js

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ethers.js (opens new window) is a JavaScript library that allows developers to interact with EVM-compatible blockchain networks.

You can use ethers.js to interact with smart contracts deployed on Rollux.

# Install

Run the following command:

npm install --save ethers
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# Setup

Before you can start using ethers.js, you need to import it into your project.

Add the following line of code to the top of your file to import ethers.js:

const ethers = require('ethers');
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# Connect to Rollux

You can connect to Rollux by instantiating a new ethers.js JsonRpcProvider object with a RPC URL of the Rollux network:

const ethers = require('ethers');

const url = 'https://rpc.rollux.com';
const provider = new ethers.providers.JsonRpcProvider(url);
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Info

Rate limiting is applied to the above public RPC server. If you are seeking premium RPC/WSS service for your dapp, refer to our list of providers.

Info

You can use the Rollux testnet by replacing the above RPC URL with https://rpc-tanenbaum.rollux.com.

# Read data from Rollux

Once you have created a provider, you can use it to read data from the Rollux network.

For example, you can use the getBlockNumber method to get the latest block:

async function getLatestBlock() {
  const latestBlock = await provider.getBlockNumber();
  console.log(latestBlock);
}
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# Write data to the blockchain

In order to write data to Rollux, you need to create a Signer.

You can create a Signer by instantiating a new ethers.js Wallet object, providing it with a private key and Provider.

const privateKey = 'PRIVATE_KEY';
const signer = new ethers.Wallet(privateKey, provider);
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Note

PRIVATE_KEY is the private key of the wallet to use when creating the account. We highly recommend using the dotenv package to help conceal private keys used in your code.

# Interact with smart contracts

You can use ethers.js to interact with a smart contract on Rollux by instantiating a Contract object using the ABI and address of a deployed contract:

const abi = [
… // ABI of deployed contract
];

const contractAddress = "CONTRACT_ADDRESS"

// read only
const contract = new ethers.Contract(contractAddress, abi, provider);
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For write-only contracts, provide a Signer object instead of a Provider object:

// write only
const contract = new ethers.Contract(contractAddress, abi, signer);
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Info

CONTRACT_ADDRESS is the address of the deployed contract.

Once you have created a Contract object, you can use it to call desired methods on the smart contract:

async function setValue(value) {
  const tx = await contract.set(value);
  console.log(tx.hash);
}

async function getValue() {
  const value = await contract.get();
  console.log(value.toString());
}
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Info

For guides on deploying contracts on Rollux, see the tutorial (opens new window).

The Rollux Client SDK