node-utils

This Node.js package contains a number of JavaScript utility functions used throughout various DuroSoft open and closed source projects. These functions are licensed under the MIT License and can be freely used however you see fit so long as attribution is retained.

Usage

$ npm install --save durosoft/node-utils

const utils = require('utils');
console.log(utils.randomAlphaNumeric(26));

Random Number Generation

utils.randomAlphaNumeric(size)

Returns a secure (thanks to secure-random) random alpha-numeric string of the specified length.

> utils.randomAlphaNumeric(32);
'BfRbHDi2kBSGnUat3OWk6i6BhF7oCnDl'

utils.randomInt(a, b)

Returns a secure random integer between a (inclusive) and b (exclusive). a and b default to 0 and the highest possible JavaScript integer, respectively, so calling randomInt() with no arguments results in a secure random positive integer over the range of all possible positive JavaScript integers (excluding the highest possible integer, since b is exclusive).

> utils.randomInt();
190759654058180
> utils.randomInt(-5, 5);
-2
> utils.randomInt(0, 100);
39

Cryptography

utils.setCryptoAlgorithm(algorithm)

Sets the current encryption/decryption algorithm used by the system. Defaults to 'aes-256-gcm', which corresponds with 256-bit AES encryption in GCM mode.

> utils.setCryptoAlgorithm('aes-128-gcm');

utils.setCryptoKey(buffer)

Sets the current encryption key used by the system, specified by a Buffer of the proper length (by default, you would want a length of 32). If you do not call this method, the default encryption key is initialized to a securely-random buffer of length 32.

> utils.setCryptoKey(secureRandom(32, {type: 'Buffer'}));

utils.saveCryptoKey(path)

Saves the current encryption key to the specified path. The key is encoded as a raw binary file.

> utils.saveCryptoKey('key.aes');

utils.loadCryptoKey(path)

Loads an encryption key that was saved using utils.saveCryptoKey(path) and sets it as the current encryption key.

> utils.loadCryptoKey('key.aes');

utils.getCryptoKey()

Retrieves the current encryption key as a raw Buffer.

> utils.getCryptoKey();
<Buffer 7b 1c c5 b5 4c e7 c5 6d 61 28 52 4b b9 1e 42 b5 0b 50 7c f3 4c a2...>

utils.generateCryptoKey()

Securely generates a securely random encryption key and sets it as current.

> utils.generateCryptoKey();

utils.encryptText(text)

Encrypts and returns the specified text using the current crypto algorithm and key. By default, a proper salt, IV, and auth tag are generated and encoded.

> utils.encryptText('hey');
'SQujuqBHpKGX87LMKvKtbw309xIe0OtRMSx9/eqpMn7BYY691PTqJcsooSt0IoqKNoUZM7...'

utils.decryptText(text)

Decrypts and returns the specified cipher text using the current crypto algorithm and key. Assumes that the text was encrypted using utils.encryptText() and the current crypto key and algorithm.

> utils.decryptText('SQujuqBHpKGX87LMKvKtbw309xIe0OtRMSx9/eqpMn7BYY691P...');
'hey'