83db/index.js

Entirely encrypted and GZip compressed JSON Database

const zlib = require("zlib");
const fs = require("fs");
const path = require("path");
const crypto = require('crypto');

class Database {
	constructor(file, options = {
		dir: "",
		decryptionKey: ""
	}) {
		file = path.join(options.dir, file);
		this.file = file;
		this.key = options.decryptionKey;
		if (fs.existsSync(file)) {
			const data = zlib.gunzipSync(fs.readFileSync(file));
			this.data = options.decryptionKey ? JSON.parse(decrypt(data.toString(), options.decryptionKey)) : JSON.parse(data);
		}
		else {
			this.data = {};
			const data = zlib.gzipSync(options.decryptionKey ? encrypt(JSON.stringify({}), options.decryptionKey) : JSON.stringify({}));
			fs.writeFileSync(file, data);
		}
	}
	get(key) {
		return this.data[key];
	}
	set(key, value) {
		this.data[key] = value;
		return this;
	}
	delete(key) {
		delete this.data[key];
		return this;
	}
	list(prefix) {
		var keys = Object.keys(this.data);
		if (prefix) {
			return keys.filter(x => x.startsWith(prefix));
		}
		return keys;
	}
	empty() {
		this.data = {};
		return this;
	}
	exists(key) {
		return !!this.data[key];
	}
	write(encryptionKey = this.key) {
		const buffer = JSON.stringify(this.data);
		const data = encryptionKey ? encrypt(buffer, encryptionKey) : buffer;
		const compressed = zlib.gzipSync(Buffer.from(data));
		fs.writeFileSync(this.file, compressed);
		return this;
	}
	getAll() {
		return this.data;
	}
	setAll(obj) {
		this.data = obj;
		return this;
	}
}

function encrypt(buffer, key) {
	let iv = crypto.randomBytes(16);
	let cipher = crypto.createCipheriv('aes-256-cbc', Buffer.from(key), iv);
	let encrypted = cipher.update(buffer);
	encrypted = Buffer.concat([
		encrypted, cipher.final()
	]);
	return iv.toString('hex') + ':' + encrypted.toString('hex');
}

function decrypt(encrypted, key) {
	let encryptedParts = encrypted.split(':');
	let iv = Buffer.from(encryptedParts.shift(), 'hex');
	let encryptedText = Buffer.from(encryptedParts + [], 'hex');
	let decipher = crypto.createDecipheriv('aes-256-cbc', Buffer.from(key), iv);
	let decrypted = decipher.update(encryptedText);
	return Buffer.concat([decrypted, decipher.final()]);
}
module.exports = Database;