crypto-random-string

What is crypto-random-string?

The crypto-random-string package is a utility for generating cryptographically strong random strings of a specified length, using Node.js's crypto module. It can be used for creating unique identifiers, tokens, or any other use cases where random strings are needed.

What are crypto-random-string's main functionalities?

Generating a random string of a specified length

This feature allows you to generate a random string with a specified length. The length is provided as an option in an object passed to the function.

const cryptoRandomString = require('crypto-random-string');

const randomString = cryptoRandomString({length: 10});
console.log(randomString);

Generating a random string with a specific type

This feature allows you to generate a random string with a specific character set, such as alphanumeric, numeric, or 'url-safe' characters.

const cryptoRandomString = require('crypto-random-string');

const alphanumericString = cryptoRandomString({length: 10, type: 'alphanumeric'});
console.log(alphanumericString);

Generating a random string with custom characters

This feature allows you to generate a random string using a custom set of characters provided by the user.

const cryptoRandomString = require('crypto-random-string');

const customString = cryptoRandomString({length: 10, characters: 'abc123'});
console.log(customString);

Other packages similar to crypto-random-string

uuid

The uuid package is used to generate universally unique identifiers (UUIDs). While crypto-random-string generates random strings of a specified length, uuid generates strings in a specific UUID format. UUIDs are often used as database keys, component identifiers, or to ensure uniqueness across distributed systems.

nanoid

NanoID is a tiny, secure, URL-friendly, unique string ID generator. Similar to crypto-random-string, it can generate random strings of various lengths and character sets. NanoID claims to be a more compact and faster alternative to UUIDs and has a smaller package size compared to crypto-random-string.

randomatic

Randomatic is a package that generates random strings based on patterns. It allows for more complex patterns and masks than crypto-random-string, such as repeating sequences and placeholders for specific character types (letters, numbers, etc.). This package offers more granular control over the structure of the generated string.

README

crypto-random-string

Generate a cryptographically strong random string

Can be useful for creating an identifier, slug, salt, PIN code, fixture, etc.

Works in Node.js and browsers.

Install

npm install crypto-random-string

Usage

import cryptoRandomString from 'crypto-random-string';

cryptoRandomString({length: 10});
//=> '2cf05d94db'

cryptoRandomString({length: 10, type: 'base64'});
//=> 'YMiMbaQl6I'

cryptoRandomString({length: 10, type: 'url-safe'});
//=> 'YN-tqc8pOw'

cryptoRandomString({length: 10, type: 'numeric'});
//=> '8314659141'

cryptoRandomString({length: 6, type: 'distinguishable'});
//=> 'CDEHKM'

cryptoRandomString({length: 10, type: 'ascii-printable'});
//=> '`#Rt8$IK>B'

cryptoRandomString({length: 10, type: 'alphanumeric'});
//=> 'DMuKL8YtE7'

cryptoRandomString({length: 10, characters: 'abc'});
//=> 'abaaccabac'

API

cryptoRandomString(options)

Returns a randomized string. Hex by default.

cryptoRandomStringAsync(options)

Returns a promise which resolves to a randomized string. Hex by default.

For most use-cases, there's really no good reason to use this async version. From the Node.js docs:

The crypto.randomBytes() method will not complete until there is sufficient entropy available. This should normally never take longer than a few milliseconds. The only time when generating the random bytes may conceivably block for a longer period of time is right after boot, when the whole system is still low on entropy.

In general, anything async comes with some overhead on it's own.

import {cryptoRandomStringAsync} from 'crypto-random-string';

await cryptoRandomStringAsync({length: 10});
//=> '2cf05d94db'

options

Type: object

length

Required
Type: number

Length of the returned string.

type

Type: string
Default: 'hex'
Values: 'hex' | 'base64' | 'url-safe' | 'numeric' | 'distinguishable' | 'ascii-printable' | 'alphanumeric'

Use only characters from a predefined set of allowed characters.

Cannot be set at the same time as the characters option.

The distinguishable set contains only uppercase characters that are not easily confused: CDEHKMPRTUWXY012458. It can be useful if you need to print out a short string that you'd like users to read and type back in with minimal errors. For example, reading a code off of a screen that needs to be typed into a phone to connect two devices.

The ascii-printable set contains all printable ASCII characters: !"#$%&\'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~ Useful for generating passwords where all possible ASCII characters should be used.

The alphanumeric set contains uppercase letters, lowercase letters, and digits: ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789. Useful for generating nonce values.

characters

Type: string
Minimum length: 1
Maximum length: 65536

Use only characters from a custom set of allowed characters.

Cannot be set at the same time as the type option.

Related

• random-int - Generate a random integer
• random-float - Generate a random float
• random-item - Get a random item from an array
• random-boolean - Get a random boolean
• random-obj-key - Get a random key from an object
• random-obj-prop - Get a random property from an object
• unique-random - Generate random numbers that are consecutively unique

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