Rollux Docs

web3.js

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web3.js is a JavaScript library that allows developers to interact with EVM-compatible blockchain networks.

You can use web3.js to interact with smart contracts deployed on Rollux.

# Install

To install the web3.js package, run:

npm install web3
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# Setup

Before you can start using web3.js, you need to import it into your project.

Add the following line of code to the top of your file to import web3.js:

const Web3 = require('web3');
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# Connect to Rollux

You can connect to Rollux by generating a new web3.js Web3 object with a RPC URL of the Rollux network:

const Web3 = require('web3');

//mainnet
const web3 = new Web3('https://rpc.rollux.com');
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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.

# Access data

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(address) {
  const latestBlock = await web3.eth.getBlockNumber();
  console.log(latestBlock.toString());
}
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# Deploy contracts

Before you can deploy a contract to the Rollux network using web3.js, you must first create an account.

You can create an account by using web3.eth.accounts:

const privateKey = “PRIVATE_KEY”;
const account = web3.eth.accounts.privateKeyToAccount(privateKey);
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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 web3.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"

const contract = new web3.eth.Contract(abi, contractAddress);
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Once you have created a Contract object, you can use it to call desired methods on the smart contract:

async function setValue(value) {
  // write query
  const tx = await contract.methods.set(value).send();
  console.log(tx.transactionHash);
}

async function getValue() {
  // read query
  const value = await contract.methods.get().call();
  console.log(value.toString());
}
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Info

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

ethers.js