Lists licenses of all direct dependencies in a monorepo (assumes packages folder). Will parse any License file if there is one and gives short format. Useful for About dialogs.

list-licenses.js

var fs = require('fs')
var path = require('path')
var cwd = typeof __dirname === 'undefined' ? process.cwd() : __dirname
var repos = fs.readdirSync('./packages').map(path => cwd+'/packages/'+path).filter(path => fs.lstatSync(path).isDirectory()).concat([cwd])
var getParent = (p, n = 1) => p.split(path.sep).slice(0, -n).join(path.sep)
var allDeps = repos
    .map(repo => repo+'/package.json')
    .filter(p => fs.existsSync(p))
    .map(package => Object.keys(require(package).dependencies).map(dep => {
        delete require.cache[dep]
        var p = path.dirname(require.resolve(dep, { paths: repos }))
        var license
        var dirs = [p, getParent(p, 1), getParent(p, 2)]
        var files = ['package.json', 'LICENSE', 'LICENSE.txt', 'LICENSE.md', 'LICENCE', 'LICENCE.txt', 'LICENCE.md']
        for (let dir of dirs) {
            for (let file of files) {
                let f = path.join(dir, file)
                if (fs.existsSync(f)) {
                    if (file === 'package.json') {
                        let l = require(f).license
                        // TODO: parse the "SEE LICENSE IN <FILENAME>", and also manually check for filenames
                        //  (like it currently does), since many repos don't list a license or they incorrectly list it
                        if (l && !l.startsWith('SEE ')) {
                            license = l
                            break
                        }
                    } else {
                        let lines = fs.readFileSync(f).toString().split('\n').map(line => line.trim()).filter(Boolean)
                        let l = lines.find(line => line.toLowerCase().match(/(licence|license)/)) || lines[0]
                        if (l) {
                            license = l
                            break
                        }
                    }
                }
            }
            if (license) {
                break
            }
        }
        return {
            [dep]: license || 'UNKNOWN'
        }
    }))
    .reduce((allDeps, deps) => allDeps.concat(deps), [])
    .reduce((allDeps, dep) => ({ ...allDeps, ...dep }))

console.log(Object.keys(allDeps).map(dep => dep + '\t' + allDeps[dep]).join('\n'))