npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

license-checker

v25.0.1

Published

Check license info for a package

Downloads

2,047,627

Readme

NPM License Checker

Build Status

As of v17.0.0 the failOn and onlyAllow arguments take semicolons as delimeters instead of commas. Some license names contain commas and it messed with the parsing

Ever needed to see all the license info for a module and its dependencies?

It's this easy:

npm install -g license-checker

mkdir foo
cd foo
npm install yui-lint
license-checker

You should see something like this:

├─ [email protected]
│  ├─ repository: http://github.com/chriso/cli
│  └─ licenses: MIT
├─ [email protected]
│  ├─ repository: https://github.com/isaacs/node-glob
│  └─ licenses: UNKNOWN
├─ [email protected]
│  ├─ repository: https://github.com/isaacs/node-graceful-fs
│  └─ licenses: UNKNOWN
├─ [email protected]
│  ├─ repository: https://github.com/isaacs/inherits
│  └─ licenses: UNKNOWN
├─ [email protected]
│  └─ licenses: MIT
├─ [email protected]
│  ├─ repository: https://github.com/isaacs/node-lru-cache
│  └─ licenses: MIT
├─ [email protected]
│  ├─ repository: https://github.com/isaacs/node-lru-cache
│  └─ licenses: MIT
├─ [email protected]
│  ├─ repository: https://github.com/isaacs/minimatch
│  └─ licenses: MIT
├─ [email protected]
│  ├─ repository: https://github.com/isaacs/minimatch
│  └─ licenses: MIT
├─ [email protected]
│  ├─ repository: https://github.com/isaacs/sigmund
│  └─ licenses: UNKNOWN
└─ [email protected]
   ├─ licenses: BSD
      └─ repository: http://github.com/yui/yui-lint

An asterisk next to a license name means that it was deduced from an other file than package.json (README, LICENSE, COPYING, ...) You could see something like this:

└─ [email protected]
   ├─ repository: https://github.com/visionmedia/debug
   └─ licenses: MIT*

Options

  • --production only show production dependencies.
  • --development only show development dependencies.
  • --start [path of the initial json to look for]
  • --unknown report guessed licenses as unknown licenses.
  • --onlyunknown only list packages with unknown or guessed licenses.
  • --json output in json format.
  • --csv output in csv format.
  • --csvComponentPrefix prefix column for component in csv format.
  • --out [filepath] write the data to a specific file.
  • --customPath to add a custom Format file in JSON
  • --exclude [list] exclude modules which licenses are in the comma-separated list from the output
  • --relativeLicensePath output the location of the license files as relative paths
  • --summary output a summary of the license usage',
  • --failOn [list] fail (exit with code 1) on the first occurrence of the licenses of the semicolon-separated list
  • --onlyAllow [list] fail (exit with code 1) on the first occurrence of the licenses not in the semicolon-seperated list
  • --packages [list] restrict output to the packages (package@version) in the semicolon-seperated list
  • --excludePackages [list] restrict output to the packages (package@version) not in the semicolon-seperated list
  • --excludePrivatePackages restrict output to not include any package marked as private
  • --direct look for direct dependencies only

Exclusions

A list of licenses is the simplest way to describe what you want to exclude.

You can use valid SPDX identifiers. You can use valid SPDX expressions like MIT OR X11. You can use non-valid SPDX identifiers, like Public Domain, since npm does support some license strings that are not SPDX identifiers.

Examples

license-checker --json > /path/to/licenses.json
license-checker --csv --out /path/to/licenses.csv
license-checker --unknown
license-checker --customPath customFormatExample.json
license-checker --exclude 'MIT, MIT OR X11, BSD, ISC'
license-checker --packages '[email protected];[email protected];[email protected]'
license-checker --excludePackages 'internal-1;internal-2'
license-checker --onlyunknown

Custom format

The --customPath option can be used with CSV to specify the columns. Note that the first column, module_name, will always be used.

When used with JSON format, it will add the specified items to the usual ones.

The available items are the following:

  • name
  • version
  • description
  • repository
  • publisher
  • email
  • url
  • licenses
  • licenseFile
  • licenseText
  • licenseModified

You can also give default values for each item. See an example in customFormatExample.json.

Requiring

var checker = require('license-checker');

checker.init({
    start: '/path/to/start/looking'
}, function(err, packages) {
    if (err) {
        //Handle error
    } else {
        //The sorted package data
        //as an Object
    }
});

Debugging

license-checker uses debug for internal logging. There’s two internal markers:

  • license-checker:error for errors
  • license-checker:log for non-errors

Set the DEBUG environment variable to one of these to see debug output:

$ export DEBUG=license-checker*; license-checker
scanning ./yui-lint
├─ [email protected]
│  ├─ repository: http://github.com/chriso/cli
│  └─ licenses: MIT
# ...

How Licenses are Found

We walk through the node_modules directory with the read-installed module. Once we gathered a list of modules we walk through them and look at all of their package.json's, We try to identify the license with the spdx module to see if it has a valid SPDX license attached. If that fails, we then look into the module for the following files: LICENSE, LICENCE, COPYING, & README.

If one of the those files are found (in that order) we will attempt to parse the license data from it with a list of known license texts. This will be shown with the * next to the name of the license to show that we "guessed" at it.