strong-license

strong-license

Simple license generator/validator using JWT with the pre-defined claim names (fields) and validation semantics.

• product - a string identifying the product the license applies to
• features - an array of strings identifying features of the product
• activationDate - a Date indicating when the license period starts
• expirationDate - a Date indicating when the license period ends
• email - a string identifing who the license is for (primarily used for logging and identification for support purposes)

Both the product and features fields support * as a wildcard to indicate that all products or features are covered by the license. When the product field is a wildcard, any product check matches but it does not imply that all features are covered. When the features list contains a wildcard as one of its entries, any feature check matches.

Usage

The strong-license module defines the License class, which can be used for generating, parsing, and validating a license key.

Generating a License Key

var License = require('strong-license').License;
var details = {
  email: '[e-mail]',
  product: 'enterprise-node',
  features: ['foo', 'bar', 'baz'],
  activationDate: new Date(),
  expirationDate: new Date(Date.now() + 1000*60*60*24*365),
};
var lic = new License(details, 'super secret key!');

process.env.LICENSE_KEY = lic.key;

It is also possible to generate a null license, which does not cover any products or features and is perpetually expired. It does, however, cover the null query scenario.

var License = require('strong-license').License;
var nullLicense = new License();

nullLicense.covers(); // => true! Can't do anything, but can do nothing!

Parsing/Validating a License Key

If a license coverage query omits a field, that field is considered a match.

var License = require('strong-license').License;
var now = new Date();
var yesterday = new Date(Date.now() - 1000*60*60*24);
var lic = new License(process.env.LICENSE_KEY, 'super secret key!');

lic.covers('enterprise-node', 'foo', now); // => true
lic.covers('myProduct', 'featurex', now); // => false

If a parameter is omitted, is considered a match.

lic.covers('enterprise-node', 'bar', null); // => true
lic.covers('enterprise-node', null, now); // => true
lic.cocers(null, 'baz', yesterday); // => false
lic.covers(); // => true! any license covers "nothing"