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@marklovett marklovett/main.js
Created Mar 13, 2018

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savjee Blockchain javascript tutorial
/**
* Description: My Blockchain tut- savjee Blockchain javascript tutorial, https://github.com/SavjeeTutorials/SavjeeCoin/blob/master/src/main.js,https://www.youtube.com/watch?v=zVqczFZr124
* Version: 1.0
* Author: Mark Lovett
* Author URI: https://marklovettdesign.com
*/
const SHA256 = require("crypto-js/sha256");
class Block {
constructor(index, timestamp, data, previousHash = '') {
this.index = index;
this.previousHash = previousHash;
this.timestamp = timestamp;
this.data = data;
this.hash = this.calculateHash();
}
calculateHash() {
return SHA256(this.index + this.previousHash + this.timestamp + JSON.stringify(this.data)).toString();
}
}
class Blockchain {
constructor() {
this.chain = [this.createGenesisBlock()];
}
createGenesisBlock() {
return new Block(0, "01/01/2017", "Genesis block", "0");
}
getLatestBlock() {
return this.chain[this.chain.length - 1];
}
addBlock(newBlock) {
newBlock.previousHash = this.getLatestBlock().hash;
newBlock.hash = newBlock.calculateHash();
this.chain.push(newBlock);
}
/*
isChainValid() {
for (let i = 1; i < this.chain.length; i++){
const currentBlock = this.chain[i];
const previousBlock = this.chain[i - 1];
if (currentBlock.hash !== currentBlock.calculateHash()) {
return false;
}
if (currentBlock.previousHash !== previousBlock.hash) {
return false;
}
}
return true;
}
}
*/
let savjeeCoin = new Blockchain();
savjeeCoin.addBlock(new Block(1, "20/07/2017", { amount: 4 }));
savjeeCoin.addBlock(new Block(2, "20/07/2017", { amount: 8 }));
console.log('Blockchain valid? ' + savjeeCoin.isChainValid());
/*
console.log('Changing a block...');
savjeeCoin.chain[1].data = { amount: 100 };
// savjeeCoin.chain[1].hash = savjeeCoin.chain[1].calculateHash();
console.log("Blockchain valid? " + savjeeCoin.isChainValid());
// console.log(JSON.stringify(savjeeCoin, null, 4));
*/
<?php
/**
* Plugin Name: My Blockchain
* Plugin URI: https://marklovettdesign.com
* Description: savjee Blockchain javascript tutorial, https://github.com/SavjeeTutorials/SavjeeCoin/blob/master/src/main.js,https://www.youtube.com/watch?v=zVqczFZr124
* Version: 1.0
* Author: Mark Lovett
* Author URI: https://marklovettdesign.com
*/
define( 'MY_BLOCKCHAIN_DIR', plugin_dir_path( __FILE__ ) );
define( 'MY_BLOCKCHAIN_URL', plugins_url( '/', __FILE__ ) );
require 'js/main.js';
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