@thzero/random-number-csprng

random-number-csprng

This is a fork of module random-number-csprng-2 without external dependencies and updated to be compatible with Node v12 and Babel v7.

A CommonJS module for generating cryptographically secure pseudo-random numbers.

Works in Node.js; This fork isn't tested in browser yet. You can help with it.

This module is based on code originally written by Scott Arciszewski, released under the WTFPL / CC0 / ZAP, random-number-csprng by Sven Slootweg, and random-number-csprng-2.

License

WTFPL or CC0, whichever you prefer.

Contributing

Pull requests welcome. Please make sure your modifications are in line with the overall code style, and ensure that you're editing the files in src/, not those in lib/.

Build tool of choice is gulp; simply run npm run build while developing, and it will watch for changes.

Be aware that by making a pull request, you agree to release your modifications under the licenses stated above.

Usage

This module will return the result asynchronously - this is necessary to avoid blocking your entire application while generating a number.

Promise example:

const randomNumberCsrpg = require("@thzero/random-number-csprng");

Promise.resolve().then(function() {
	return randomNumberCsrpg(10, 30);
}).then(function(number) {
	console.log("Your random number:", number);
}).catch(function(err) {
	console.log("Something went wrong: " + err.code);
});

Await example:

const randomNumberCsrpg = require("@thzero/random-number-csprng");
const randomNumber = await randomNumberCsrpg(10, 30);

API

randomNumber(minimum, maximum, [cb])

Returns a Promise that resolves to a random number within the specified range.

Note that the range is inclusive, and both numbers must be integer values. It is not possible to securely generate a random value for floating point numbers, so if you are working with fractional numbers (eg. 1.24), you will have to decide on a fixed 'precision' and turn them into integer values (eg. 124).

• minimum: The lowest possible value in the range.
• maximum: The highest possible value in the range. Inclusive.

Optionally also accepts a nodeback as cb, but seriously, you should be using Promises.

randomNumber.RandomGenerationError

Any errors that occur during the random number generation process will be of this type. The error object will also have a code property, set to the string "RandomGenerationError".

The error message will provide more information, but this kind of error will generally mean that the arguments you've specified are somehow invalid.

Notes

Don't use ranges any bigger than 2^32 - 1 or 4,294,97,295. Details in Issue #4 of the original module.

This fork isn't tested in browser yet. You can help with it.