Unlock the Power of Cryptocurrency with JavaScript

What is a Blockchain?

A blockchain is an unalterable chain of data, comprising blocks containing transaction information. Each block has a unique hash value, which can be verified to ensure its legitimacy. Since blocks are linked together, any attempt to alter existing blocks would be detected, ensuring the integrity of the blockchain.

Getting Started

To create our JavaScript cryptocurrency, we’ll need:

• Node.js installed on your machine
• A code editor (Visual Studio Code is a popular choice)
• Working knowledge of Node

You can refer to the GitHub repository for the complete code.

Creating the Transaction Class

Our cryptocurrency will involve four classes: Transaction, Block, Chain, and Wallet. Let’s start with the Transaction class, which will have properties for amount, senderPublicKey, and receiverPublicKey. We’ll also create a method to convert the object to a string, allowing us to generate a hash later.

class Transaction {
  constructor(amount, senderPublicKey, receiverPublicKey) {
    this.amount = amount;
    this.senderPublicKey = senderPublicKey;
    this.receiverPublicKey = receiverPublicKey;
  }

  toString() {
    return `${this.amount} ${this.senderPublicKey} ${this.receiverPublicKey}`;
  }
}

Creating the Block Class

The Block class will represent individual blocks in our blockchain. We’ll set up constructors and properties for previousHash, transaction, and timestamp. A crucial function will generate a hash of the block, ensuring its legitimacy.

class Block {
  constructor(previousHash, transaction, timestamp) {
    this.previousHash = previousHash;
    this.transaction = transaction;
    this.timestamp = timestamp;
    this.hash = this.generateHash();
  }

  generateHash() {
    // Hash generation logic goes here
  }
}

Creating the Chain Class

The Chain class will hold all the blocks in our blockchain. We’ll initialize the chain with a dummy block and create functions to get the last hash of the chain and insert new blocks.

class Chain {
  constructor() {
    this.chain = [this.createDummyBlock()];
  }

  createDummyBlock() {
    // Dummy block creation logic goes here
  }

  getLastHash() {
    return this.chain[this.chain.length - 1].hash;
  }

  insertBlock(newBlock) {
    newBlock.previousHash = this.getLastHash();
    this.chain.push(newBlock);
  }
}

Creating the Wallet Class

The Wallet class will represent user wallets, each with a public and private key pair. We’ll create a constructor to generate a key pair and a function to send cryptocurrencies to other wallets on the network.

class Wallet {
  constructor() {
    this.keyPair = this.generateKeyPair();
  }

  generateKeyPair() {
    // Key pair generation logic goes here
  }

  sendCryptocurrency(amount, receiverPublicKey) {
    // Transaction creation and sending logic goes here
  }
}

Testing Our Cryptocurrency

Now that we’ve set up our classes, let’s test our cryptocurrency by creating wallets and sending transactions between them. You can experiment further by incorporating a wallet balance system and mining system into this project.

const wallet1 = new Wallet();
const wallet2 = new Wallet();

wallet1.sendCryptocurrency(10, wallet2.publicKey);

What’s Next?

While this tutorial provides a solid foundation for creating a cryptocurrency, it’s essential to remember that a production-level cryptocurrency requires additional security measures, such as mining and advanced encryption. Feel free to explore and learn more about the world of cryptocurrency development.