nlm/lib/license/index.js

Lifecycle manager for node projects

/*
 * Copyright (c) 2015, Groupon, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * Neither the name of GROUPON nor the names of its contributors may be
 * used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

'use strict';

const fs = require('fs');

const path = require('path');

const { promisify } = require('util');

const debug = require('debug')('nlm:license');

const globAsync = promisify(require('glob'));

const readFileAsync = promisify(fs.readFile);
const writeFileAsync = promisify(fs.writeFile);

function flatten(arrs) {
  return [].concat.apply([], arrs);
}

const COMMENT_TYPES = {
  '.js': {
    getLicenseHeader: function getLicenseHeader(licenseText) {
      const body = licenseText
        .split('\n')
        .map(line => {
          return ` ${`* ${line}`.trim()}`;
        })
        .join('\n');
      return `/*\n${body}\n */`;
    },
  },
  '.coffee': {
    getLicenseHeader: function getLicenseHeader(licenseText) {
      return `###\n${licenseText}\n###`;
    },
  },
};

function collectFiles(cwd, whitelist, optionalExclude) {
  const exclude = ['node_modules/**/*', './node_modules/**/*'].concat(
    optionalExclude || []
  );

  function scanDirectory(directory) {
    return globAsync(`${directory}/**/*.{js,jsx,mjs,ts,tsx,coffee}`, {
      ignore: exclude,
      nodir: true,
      cwd,
      root: cwd, // so /lib works as "expected"
    });
  }

  return Promise.all((whitelist || ['.']).map(scanDirectory))
    .then(flatten)
    .then(filenames =>
      Promise.all(
        filenames.map(relFilename => {
          const filename = path.join(cwd, relFilename);
          return readFileAsync(filename, 'utf8').then(content => ({
            filename,
            content,
          }));
        })
      )
    );
}

function maskYears(str) {
  return str.replace(/\b\d{4}\b/g, 'YYYY');
}

// ignore year changes for purposes of license header presence
function hasNoLicenseHeader(entry) {
  return !maskYears(entry.content).includes(maskYears(entry.licenseHeader));
}

function addLicenseHeader(entry) {
  debug('Adding license', entry.filename);
  entry.content = `${entry.licenseHeader}\n${entry.content}`;
  return entry;
}

function addMissingLicenseHeaders(licenseText, files) {
  const licenseHeaders = {
    '.js': COMMENT_TYPES['.js'].getLicenseHeader(licenseText),
    '.jsx': COMMENT_TYPES['.js'].getLicenseHeader(licenseText),
    '.mjs': COMMENT_TYPES['.js'].getLicenseHeader(licenseText),
    '.ts': COMMENT_TYPES['.js'].getLicenseHeader(licenseText),
    '.tsx': COMMENT_TYPES['.js'].getLicenseHeader(licenseText),
    '.coffee': COMMENT_TYPES['.coffee'].getLicenseHeader(licenseText),
  };
  return files
    .map(file => {
      file.licenseHeader = licenseHeaders[path.extname(file.filename)];
      return file;
    })
    .filter(hasNoLicenseHeader)
    .map(addLicenseHeader);
}

// replaces first instance of things like (c) 2005 with (c) 2021 (current yr)
function replaceCopyrightYear(str) {
  const curYear = new Date().getFullYear();
  return str.replace(/((?:\(c\)|©)\s)(?:\d{4}|YYYY)/, `$1${curYear}`);
}

async function getLicenseText(cwd) {
  try {
    const rawText = await readFileAsync(path.join(cwd, 'LICENSE'), 'utf8');
    return replaceCopyrightYear(rawText.trim());
  } catch (error) {
    if (error.code === 'ENOENT') {
      return null;
    }
    throw error;
  }
}

function collectMissingHeaders(cwd, whitelist, optionalExclude, licenseText) {
  // No license available?
  if (licenseText === null) {
    debug('No LICENSE file found, skipping license headers');
    return [];
  }

  return collectFiles(cwd, whitelist, optionalExclude).then(
    addMissingLicenseHeaders.bind(null, licenseText)
  );
}

function writeLicenseHeaders(entry) {
  return writeFileAsync(entry.filename, entry.content, 'utf8').then(
    () => entry.filename
  );
}

function addLicenseHeaders(cwd, whitelist, optionalExclude) {
  return getLicenseText(cwd)
    .then(collectMissingHeaders.bind(null, cwd, whitelist, optionalExclude))
    .then(hdrs => Promise.all(hdrs.map(writeLicenseHeaders)));
}

module.exports = addLicenseHeaders;
addLicenseHeaders.collectMissing = collectMissingHeaders;