feat: add allow only option

README.md

@@ -71,15 +71,19 @@ node_modules/.bin/license-checker scan --failOn <license>
 
 #### 🚩 <a name="options"></a>Options
 
-| Option | Description | Requiered | Type | Default |
-|---|---|---|---|---|
-| --start | Path of the initial json to look for | false | string | `process.cwd()` |
-| --failOn | Fail (exit with code 1) if any package license does not satisfies any license in the provided list | true | string[] |  |
-| --outputFileName | Name of the report file generated | false | string | `license-report-<timestamp>.md` |
-| --errorReportFileName | Name of the error report file generated when a license in the `failOn` option is found | false | string | `license-error-<timestamp>.md` |
-| --disableErrorReport | Flag to disable the error report file generation | false | boolean  | `false` |
-| --disableReport | Flag to disable the report file generation, whether there is an error or not | false | boolean | `false` |
-| --customHeader | Name of a text file containing the custom header to add at the start of the generated report | false | string | This application makes use of the following open source packages: |
+| Option                | Description                                                                                                           | Requiered | Type | Default |
+|-----------------------|-----------------------------------------------------------------------------------------------------------------------|---|---|---|
+| --start               | Path of the initial json to look for                                                                                  | false | string | `process.cwd()` |
+| --failOn              | Fail (exit with code 1) if at least one package license **satisfies** one of the licenses in the provided list        | true | string[] |  |
+| --allowOnly           | Fail (exit with code 1) if at least one package license **does not satisfy** one of the licenses in the provided list | true | string[] |  |
+| --outputFileName      | Name of the report file generated                                                                                     | false | string | `license-report-<timestamp>.md` |
+| --errorReportFileName | Name of the error report file generated when a license in the `failOn` option is found                                | false | string | `license-error-<timestamp>.md` |
+| --disableErrorReport  | Flag to disable the error report file generation                                                                      | false | boolean  | `false` |
+| --disableReport       | Flag to disable the report file generation, whether there is an error or not                                          | false | boolean | `false` |
+| --customHeader        | Name of a text file containing the custom header to add at the start of the generated report                          | false | string | This application makes use of the following open source packages: |
+
+
+> ❗The options `--failOn` and `--allowOnly` are mutually exclusive. You must use one of them.
 
 ## 🧑‍💻 <a name="examples"></a>Examples
 
@@ -95,7 +99,7 @@ If the value provided is not SPDX compliant, the process fails (exit error 1).
 
 ### scan command
 
-All the values provided in the `failOn` list must be [SPDX](https://spdx.dev/specifications/) compliant. Otherwise, an error will be thrown (exit error 1). 
+All the values provided in the `failOn` or `allowOnly` list must be [SPDX](https://spdx.dev/specifications/) compliant. Otherwise, an error will be thrown (exit error 1). 
 Check the [SPDX license list](https://spdx.org/licenses/).
 
 ```sh
@@ -105,14 +109,30 @@ npx @onebeyond/license-checker scan --failOn MIT GPL-1.0+
 The input list is transformed into a SPDX expression with the `OR` logical operator. In the example, that is `MIT OR GPL-1.0+`.
 If any of the packages' licenses satisfies that expression, the process fails (exit error 1).
 
+SPDX compliance and `OR` input concatenation also apply for the `allowOnly` option:
+
+```sh
+npx @onebeyond/license-checker scan --allowOnly MIT GPL-1.0+
+```
+
+In this case, all the packages' licenses must be either `MIT` or `GPL-1.0+`.
+
+Arguments to `failOn` and `allowOnly` are not limited to one license. Expressions with logical operators are also accepted:
+
+```sh
+npx @onebeyond/license-checker scan --allowOnly "MIT AND Apache-2.0" GPL-1.0+
+```
+
+In this example, all the packages' licenses must be either `MIT AND Apache-2.0` **or** `GPL-1.0+`.
+
 ## 🔗 Useful links
 
 - [Licensing a repository](https://docs.github.com/en/github/creating-cloning-and-archiving-repositories/licensing-a-repository)
 - [Choose a license](https://choosealicense.com/appendix/)
 
 ## ⚠️ Temporal issue
 
-An issue in `spdx-satisfies` has been found and it's pending resolution. Until then, GFDL 1x licenses are not supported and an error will be thrown if either packages or failOn arguments contain it. 
+An issue in `spdx-satisfies` has been found, and it's pending resolution. Until then, GFDL 1x licenses are not supported and an error will be thrown if either packages or failOn arguments contain it. 
 
 ## Contributors ✨
 

cli.js

@@ -1,10 +1,12 @@
 const yargs = require('yargs')(process.argv.slice(2));
+const { checkArgs } = require('./src/utils');
 
 // https://github.com/yargs/yargs/blob/main/docs/advanced.md#commanddirdirectory-opts
 module.exports = yargs
   .parserConfiguration({ 'camel-case-expansion': false })
   .commandDir('commands')
   .demandCommand()
+  .check(checkArgs)
   .help()
   .alias('help', 'h')
   .argv;

commands/scan.js

@@ -19,9 +19,14 @@ exports.builder = {
     default: process.cwd()
   },
   failOn: {
-    description: 'fail (exit with code 1) if any package license does not satisfies any license in the provided list',
+    description: 'fail (exit with code 1) if at least one package license satisfies one of the licenses in the provided list ',
     type: 'array',
-    demandOption: true
+    conflicts: 'allowOnly'
+  },
+  allowOnly: {
+    description: 'fail (exit with code 1) if at least one package license does not satisfy one of the licenses in the provided list',
+    type: 'array',
+    conflicts: 'failOn'
   },
   outputFileName: {
     description: 'name of the output file generated',

src/runner.js

@@ -25,18 +25,22 @@ const check = (license) => {
 };
 
 const scan = async (options) => {
-  const { failOn } = options;
+  const { failOn, allowOnly } = options;
 
-  if (!failOn) throw new Error('Error: You must provide a list of licenses to fail on in the "failOn" option.');
+  const allowSelected = !!allowOnly;
+  const licensesList = allowSelected ? allowOnly : failOn;
 
-  checkLicenseError(failOn); // @TODO Remove after issue has been solved
-  checkSPDXCompliance(failOn);
-  const bannedLicenses = generateSPDXExpression(failOn);
+  checkLicenseError(licensesList); // @TODO Remove after issue has been solved
+  checkSPDXCompliance(licensesList);
+  const spdxLicensesExpression = generateSPDXExpression(licensesList);
 
   const packages = await checker.parsePackages(options.start);
   const packageList = getPackageInfoList(packages);
 
-  const { forbidden: forbiddenPackages, nonCompliant: invalidPackages } = checkPackagesLicenses(bannedLicenses, packageList);
+  const {
+    forbidden: forbiddenPackages,
+    nonCompliant: invalidPackages
+  } = checkPackagesLicenses(spdxLicensesExpression, packageList, allowSelected);
   if (invalidPackages.length) {
     logger.warn(`The following package licenses are not SPDX compliant and cannot be validated:\n${invalidPackages.map(pkg => ` > ${pkg.package} | ${pkg.licenses}`).join('\n')}`);
   }

src/utils.js

@@ -41,7 +41,7 @@ const formatForbiddenLicenseError = licenses => {
       [licenses]: !stats[licenses] ? 1 : stats[licenses] + 1
     }), {});
 
-  const header = `Found ${licenses.length} packages with licenses defined by the --failOn flag:`;
+  const header = `Found ${licenses.length} packages with licenses defined by the provided option:`;
   const lines = Object
     .entries(forbiddenLicenseStats)
     .map(([license, value]) => ` > ${value} packages with license ${license}`)
@@ -66,7 +66,7 @@ const checkSPDXCompliance = (licenses = []) => {
   const invalidLicenses = licenses.filter(arg => !isSPDXCompliant(arg));
   if (invalidLicenses.length) {
     throw new Error(
-      `The following licenses are not SPDX compliant. Please, use the --checkLicense option to validate your input:\n${invalidLicenses.join(' | ')}`
+      `The following licenses are not SPDX compliant. Please, use the "check" command to validate your input:\n${invalidLicenses.join(' | ')}`
     );
   }
 };
@@ -80,7 +80,7 @@ const checkLicenseError = (licenses = []) => {
   const errorLicenses = licenses.some(isLicenseError);
   if (errorLicenses) {
     throw new Error(
-      'Your failOn list contains a GFDL-1.x licenses and they are temporary unallowed. There\'s an issue pending to solve.'
+      'Your licenses list contains a GFDL-1.x licenses and they are temporary unallowed. There\'s an issue pending to solve.'
     );
   }
 };
@@ -93,37 +93,62 @@ const checkLicenseError = (licenses = []) => {
  */
 const isLicenseError = (license = '') => licensesExceptions.includes(license);
 
+/**
+ * Filter out licenses from the SPDX complete list depending on the value of the shouldSatisfy flag.
+ * @param {string} expression - A valid SPDX expression
+ * @param {boolean} shouldSatisfy - If true, the result will yield all the licenses that satisfies the incoming expression. If false,
+ * the result will yield any other license that do not match the expression
+ * @return {string[]} - List of resulting licenses
+ */
+const getValidLicenses = (expression, shouldSatisfy) => spdxIds.filter(id => {
+  if (isLicenseError(id)) return false;// @TODO Refactor after issue has been solved
+  const isSatisfied = satisfiesSPDXLicense(id, expression);
+  return shouldSatisfy ? isSatisfied : !isSatisfied;
+});
+
 /**
  * Subtracts the expression from the full list of SPDX ids and check the result (the allowed licenses) against the list of packages.
  * If the license of the package itself is not SPDX compliant, the package will be included on the "nonCompliant" list.
  * If a package license does not satisfy the allowed SPDX id list, the package will be included on the "forbidden" list.
  * @param {string} expression - A SPDX expression
  * @param {object[]} packages - A list of packages to be checked against the SPDX expression
+ * @param {boolean} allow - Determines the license check. If true, forbidden will contain all the packages that
+ * do not comply with the expression. If false, forbidden will contain all the packages that comply with the expression
  * @return {{forbidden: object[], nonCompliant: object[]}} - A couple of lists including the packages that satisfy the SPDX expression
  * and the packages with a non SPDX compliant license
  */
-const checkPackagesLicenses = (expression, packages) => {
-  const validSpdxIds = expression && spdxIds.filter(id => !isLicenseError(id) && !satisfiesSPDXLicense(id, expression)); // @TODO Refactor after issue has been solved
-  const allowedLicensesExp = expression && generateSPDXExpression(validSpdxIds);
+const checkPackagesLicenses = (expression, packages, allow = false) => {
+  const validSpdxIds = getValidLicenses(expression, allow);
+
+  const allowedLicensesExp = generateSPDXExpression(validSpdxIds);
 
   return packages.reduce((total, pkg) => {
     const { licenses } = pkg;
 
     if (!isSPDXCompliant(licenses)) return { ...total, nonCompliant: [...total.nonCompliant, pkg] };
 
-    const isSatisfiedLicense = expression && !satisfiesSPDXLicense(licenses, allowedLicensesExp);
-    if (isSatisfiedLicense) return { ...total, forbidden: [...total.forbidden, pkg] };
+    if (!satisfiesSPDXLicense(licenses, allowedLicensesExp)) return { ...total, forbidden: [...total.forbidden, pkg] };
 
     return total;
   }, { forbidden: [], nonCompliant: [] });
 };
 
+const checkArgs = (args) => {
+  if (args._[0] === 'scan') {
+    const { failOn, allowOnly } = args;
+    if (!failOn && !allowOnly) throw new Error('You need to provide the "failOn" or "allowOnly" option.');
+    if ((failOn && !failOn.length) || (allowOnly && !allowOnly.length)) throw new Error('You need to provide at least one license.');
+  }
+  return true;
+};
+
 module.exports = {
   getPackageInfoList,
   formatForbiddenLicenseError,
   generateSPDXExpression,
   checkSPDXCompliance,
   checkPackagesLicenses,
   isLicenseError,
-  checkLicenseError
+  checkLicenseError,
+  checkArgs
 };