Licenses
Licenses.. This is the most painful part about Open Source. There are so many different licenses and they all have different restrictions. In order to know the license footprint of your project you need to know how your modules are licensed. You might be interested in your license footprint because:
- Some licenses might restrict you from selling your code or using it for
- There are unlicensed modules released in to npm on a daily basis. Just
- The code could be proprietary licensed.
- .. and the list goes on and on.
But the biggest problem is figuring out which license a module is actually using. There are a lot of ways of saying that your code is licensed under MIT. There are people who rather say licensed under MIT than just stating MIT. So the way we write which license we use differ but also the location of our licenses. It can be in the
package.json
hiding in various of properties or specified in
the README.md
of the project or even a dedicated LICENSE
file in the
repository.Now that you've taken the time to read about some of these issues above, you know why this module exists. It tries to fulfill one simple task. Get a human readable license from a given node module.
However, this module isn't flawless as it tries to automate a task that usually requires the interference and intelligence of a human. If you have module that is incorrectly detected or not detected at all but does have licensing information publicly available please create an issue about and we'll see if it can get resolved.
Installation
The module is released through npm and can therefor be installed using:npm install --save licenses
CLI
There is CLI version of this module available aslicensing
which can be
installed locally using:npm install -g licensing
See https://github.com/3rd-Eden/licensing for more information.
Getting started with the API
The module exposes one single interface for retrieving the packages, which is a simple exported function:'use strict';
var licenses = require('licenses');
licenses('primus', function fetched(err, license) {
console.log(license.join(',')); // MIT
});
As you can see in the example above, the first argument of the function can be a
string
with the name of the package you want to resolve. In addition to
supplying a string you can also give it the contents of the npm registry's data
directly:licenses({ name: 'primus', readme: '..', ....}, function fetched(err, license) {
});
The function allows a second optional argument which allows you to configure license function. The following options are supported:
- githulk A custom or pre-authorized
- order The order in which we should attempt to resolve the license. This
- registry The URL of The npm Registry we should use to retrieve package
- npmjs a custom npm-registry instance.
The options are completely optional and can therefore be safely omitted.
licenses('primus', { registry: 'https://registry.npmjs.org/' }, function () {
});
As you might have noticed from the options we support three different lookup algorithms:
registry
In this algorithm we attempt to search for license information directly in the supplied or retrieved npm data. This is the fastest lookup as it only needs to search and parse thelicense
and licenses
fields of the module for license
information.