With this package, you can create Random Numbers and Timestamp Based Random Numbers with low probability of collision using strong randomized bytes as seeds. You can specify the min and max lengths (which will generate a random length between this values) or configure a specific length.

With npm:

npm i js-random-number

Or just clone this repository and import the ./JsRandomNumber.js file into your application.

https://github.com/Maykonn/js-random-number.git

Random Numbers are generated with strong randomized bytes to seed the random number generation algorithm using the Node.js crypto module. The most simple way to generate a random number is:

const JsRandomNumber = require('js-random-number');
  
const RandomNumber = new JsRandomNumber.Generator();
console.log('Random Number:');
console.log(RandomNumber.getNumber());
console.log('\n');
console.log('Random Number Value:', RandomNumber.getNumber().getValue());

The console response might be:

Random Number:
RandomNumber {
  _configuration: 
   Configuration {
     _minLength: NumberLength { _value: 8 },
     _maxLength: NumberLength { _value: 16 },
     _timestampBased: false },
  _length: NumberLength { _value: 14 },
  _value: 83381838615074 }
  
Random Number Value: 83381838615074

Note that the min and max length are randomly generated and that the length generated is 14 that accomplishes the configuration requirements. But, when necessary you can configure the min and max length manually using the Configuration object:

const JsRandomNumber = require('js-random-number');
const NumberConfig = new JsRandomNumber.Configuration();
  
NumberConfig.setMinLength(4);
NumberConfig.setMaxLength(10);
  
const RandomNumber = new JsRandomNumber.Generator(NumberConfig);
console.log('Random Number:');
console.log(RandomNumber.getNumber());

And now the console response will be different:

Random Number:
RandomNumber {
  _configuration: 
   Configuration {
     _minLength: NumberLength { _value: 4 },
     _maxLength: NumberLength { _value: 10 },
     _timestampBased: false },
  _length: NumberLength { _value: 6 },
  _value: 264841 }

Maybe you want to generate numbers with a specific length, you might do:

const JsRandomNumber = require('js-random-number');
const NumberConfig = new JsRandomNumber.Configuration();
NumberConfig.setLength(6);

That's will configure to 6 the number length.

The random number rules are:

• The number max length never will be greater than the Number.MAX_SAFE_INTEGER length
• The length can be between the min and max length

The same way which random numbers the timestamp based numbers are generated with strong randomized bytes to seed the generation randomness, but the number will be randomized with timestamp as the start, which decreases the collision probability.

const JsRandomNumber = require('js-random-number');
  
const NumberConfig = new JsRandomNumber.Configuration();
NumberConfig.timestampBased();
  
const RandomNumberTimestampBased = new JsRandomNumber.Generator(NumberConfig);
console.log('Random Number timestamp based:');
console.log(RandomNumberTimestampBased.getNumber());

The timestamp based random number rules are:

• The number min length never will be less than the timestamp length
• The number max length never will be greater than the Number.MAX_SAFE_INTEGER length
• The length can be between the min and max length

Another important note about Timestamp Based Numbers is that the algorithm can generate a random pad value to accomplish the configured length to generate the number. For example, suppose that you want a number with a length between the max safe length and timestamp length, and based on timestamp, you might do:

const JsRandomNumber = require('js-random-number');
  
const NumberConfig = new JsRandomNumber.Configuration();
NumberConfig.timestampBased();
NumberConfig.setMaxLength(JsRandomNumber.NumberLength.getMaxSafeLength());
  
const RandomNumberTimestampBased = new JsRandomNumber.Generator(NumberConfig);
console.log('Random Number timestamp based:');
console.log(RandomNumberTimestampBased.getNumber());

The console response might be:

Random Number timestamp based:
RandomNumberTimestampBased {
  _configuration: 
   Configuration {
     _minLength: NumberLength { _value: 13 },
     _maxLength: NumberLength { _value: 16 },
     _timestampBased: true },
  _length: NumberLength { _value: 15 },
  _value: 728172850677692,
  _padLength: NumberLength { _value: 2 },
  _timestamp: 1538153492112,
  _timestampLength: NumberLength { _value: 13 } }

This example padded with a length of 2 decreases a lot the collision probability even for calls executes at same millisecond.

If you need help with this bundle please consider open a question on StackOverflow using the js-random-number tag, it is the official support platform for this bundle.

Github Issues are dedicated to bug reports and feature requests.

You can contribute to this project cloning this repository and in your clone you just need to create a new branch using a name related to the new functionality which you'll create.
When you finish your work, you just need to create a pull request which will be revised, merged to master branch (if the code doesn't break the project) and published as a new release.