copitpastit/src/crypto.js

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

const HASH = 'sha256';
const DIGEST = 'base64url';

function cryptoFile(path) {
    return crypto.createHash(HASH).update(fs.readFileSync(path)).digest(DIGEST);
}

function cryptoString(input) {
    return crypto.createHash(HASH).update(input).digest(DIGEST);
}

function publicKey(priv) {
    return cryptoString(priv).substr(0, 24);
}

module.exports = {
    file: cryptoFile,
    string: cryptoString,
    publicKey: publicKey
}