validate-npm-package-license

What is validate-npm-package-license?

The validate-npm-package-license package is used to validate and parse license identifiers based on the SPDX license list. It helps ensure that package licenses are valid and SPDX-compliant, which is important for legal compliance and software distribution.

What are validate-npm-package-license's main functionalities?

License Validation

This feature allows you to validate a string to check if it's a valid SPDX license expression. The code sample demonstrates how to validate the 'MIT' license identifier.

"use strict";\nconst validate = require('validate-npm-package-license');\nconst result = validate('MIT');\nconsole.log(result);

License Parsing

This feature enables parsing of complex SPDX license expressions, such as dual licenses. The code sample shows how to parse and validate a compound license expression that includes both 'MIT' and 'Apache-2.0' licenses.

"use strict";\nconst validate = require('validate-npm-package-license');\nconst result = validate('(MIT OR Apache-2.0)');\nconsole.log(result);

Other packages similar to validate-npm-package-license

spdx-correct

The spdx-correct package is designed to help correct invalid SPDX license IDs to their nearest valid identifiers. It is similar to validate-npm-package-license in that it deals with SPDX licenses, but it focuses more on correcting typos and common mistakes rather than validation.

spdx-expression-parse

This package provides functionality to parse SPDX license expressions, similar to one of the features of validate-npm-package-license. However, spdx-expression-parse focuses solely on parsing and does not include validation against the SPDX license list.

README

validate-npm-package-license

Give me a string and I'll tell you if it's a valid npm package license string.

var valid = require('validate-npm-package-license');

SPDX license identifiers are valid license strings:

var assert = require('assert');
var validSPDXExpression = {
  validForNewPackages: true,
  validForOldPackages: true,
  spdx: true
};

assert.deepEqual(valid('MIT'), validSPDXExpression);
assert.deepEqual(valid('BSD-2-Clause'), validSPDXExpression);
assert.deepEqual(valid('Apache-2.0'), validSPDXExpression);
assert.deepEqual(valid('ISC'), validSPDXExpression);

The function will return a warning and suggestion for nearly-correct license identifiers:

assert.deepEqual(
  valid('Apache 2.0'),
  {
    validForOldPackages: false,
    validForNewPackages: false,
    warnings: [
      'license should be ' +
      'a valid SPDX license expression (without "LicenseRef"), ' +
      '"UNLICENSED", or ' +
      '"SEE LICENSE IN <filename>"',
      'license is similar to the valid expression "Apache-2.0"'
    ]
  }
);

SPDX expressions are valid, too ...

// Simple SPDX license expression for dual licensing
assert.deepEqual(
  valid('(GPL-3.0-only OR BSD-2-Clause)'),
  validSPDXExpression
);

... except if they contain LicenseRef:

var warningAboutLicenseRef = {
  validForOldPackages: false,
  validForNewPackages: false,
  spdx: true,
  warnings: [
    'license should be ' +
    'a valid SPDX license expression (without "LicenseRef"), ' +
    '"UNLICENSED", or ' +
    '"SEE LICENSE IN <filename>"',
  ]
};

assert.deepEqual(
  valid('LicenseRef-Made-Up'),
  warningAboutLicenseRef
);

assert.deepEqual(
  valid('(MIT OR LicenseRef-Made-Up)'),
  warningAboutLicenseRef
);

If you can't describe your licensing terms with standardized SPDX identifiers, put the terms in a file in the package and point users there:

assert.deepEqual(
  valid('SEE LICENSE IN LICENSE.txt'),
  {
    validForNewPackages: true,
    validForOldPackages: true,
    inFile: 'LICENSE.txt'
  }
);

assert.deepEqual(
  valid('SEE LICENSE IN license.md'),
  {
    validForNewPackages: true,
    validForOldPackages: true,
    inFile: 'license.md'
  }
);

If there aren't any licensing terms, use UNLICENSED:

var unlicensed = {
  validForNewPackages: true,
  validForOldPackages: true,
  unlicensed: true
};
assert.deepEqual(valid('UNLICENSED'), unlicensed);
assert.deepEqual(valid('UNLICENCED'), unlicensed);