crypto-example.js

const fs = require('fs')
const crypto = require('crypto')

const publicKey = fs.readFileSync('public.pem')
const privateKey = fs.readFileSync('private.pem')

const message = 'Hello, world!'

const encryptedMsg = crypto.publicEncrypt(publicKey, Buffer.from(message, 'utf8'))
console.log('encrypted by private key: ' + encryptedMsg.toString('hex'))

const decryptedMsg = crypto.privateDecrypt(privateKey, encryptedMsg);
console.log('decrypted by public key: ' + decryptedMsg.toString('utf8'));