@metamask/license-checker
v26.0.1
Published
Check license info for a package
Downloads
518
Readme
NPM License Checker
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 @metamask/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
- 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 errorslicense-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.