Proof of Work Example

proofOfWork.js

const crypto = require("crypto");

// PROOF OF WORK EXAMPLE

const RANDOM_SIZE = 32;

const HARDNESS = 6;
const hardnessPrefix = "0".repeat(HARDNESS);

const start = new Date().getTime();

let i = 0;
let random;
let result;
do {
  random = crypto.randomBytes(RANDOM_SIZE);
  result = crypto
    .createHash("sha256")
    .update(random.toString("hex"))
    .digest("hex");
  i++;
} while (!result.toString("hex").startsWith(hardnessPrefix));

const end = new Date().getTime();

console.log(`${i} iterations (${end - start}):`);
console.log(random.toString("hex"));
console.log(result.toString("hex"));