Blockchain Development Programming Tutorials, Guides & Best Practices

When developing cryptographic applications in JavaScript, one common requirement is the generation of cryptographically secure random bytes. Two popular methods for doing this are crypto.randomBytes from Node.js's built-in crypto module, and ethers.randomBytes from the ethers.js library, which is often used for Ethereum-related operations. Both functions serve the same purpose, but they have some key differences. Let’s explore these two methods in detail.

• crypto.randomBytes:
• Library: crypto.randomBytes is part of Node.js’s built-in crypto module. It requires no additional dependencies and is readily available in any Node.js environment.
• Usage: The function takes a single argument specifying the number of bytes to generate and returns a Buffer object containing the random bytes.
• Example:

• Equality Check:

  console.log(num1.eq(num2)); // false

• Node.js installed on your machine.
• A basic understanding of JavaScript.
• An Etherscan API key (explained below).
• Familiarity with Ethers.js for blockchain interaction.

To use the Etherscan API, you’ll need to get an API key. Here’s how:

Use Infura when you need to interact with the Ethereum blockchain in real-time. Infura allows you to send transactions, deploy contracts, and interact with smart contracts. It is essential for decentralized applications (dApps) and any use case where you need to write to the blockchain.

const ethers = require('ethers');

// Replace with your Infura Project ID
const infuraProvider = new ethers.JsonRpcProvider('https://mainnet.infura.io/v3/YOUR_INFURA_PROJECT_ID');

// Replace with your wallet's private key
const privateKey = 'YOUR_PRIVATE_KEY';

// Create a wallet instance and connect it to Infura
const wallet = new ethers.Wallet(privateKey, infuraProvider);

// Replace with the recipient's Ethereum address
const recipientAddress = '0xRecipientEthereumAddress';

// Amount to send (in Ether)
const amountInEther = '0.01';

async function sendTransaction() {
  try {
    const tx = {
      to: recipientAddress,
      value: ethers.utils.parseEther(amountInEther),
      gasLimit: 21000, // Gas limit for a basic transaction
      gasPrice: await infuraProvider.getGasPrice() // Get current gas price from Infura
    };

    // Send the transaction
    const transaction = await wallet.sendTransaction(tx);
    console.log('Transaction Hash:', transaction.hash);

    // Wait for the transaction to be mined
    const receipt = await transaction.wait();
    console.log('Transaction Confirmed:', receipt);
  } catch (error) {
    console.error('Error sending transaction:', error);
  }
}

sendTransaction();

You’ll use Ethers.js to interact with Ethereum smart contracts and send transactions. Run the following command in your project folder to install it:

npm install ethers