udk-webpack4.ts

// Copyright (c) 2018 Steven Enten. All rights reserved. Licensed under the MIT license.

process.exitCode = 0;

/**
 * @param {string} command process to run
 * @param {string[]} args commandline arguments
 * @returns {Promise<void>} promise
 */
const runCommand = (command: string, args: string[]) => {
  const cp = require('child_process');

  return new Promise<void>((resolve, reject) => {
    const executedCommand = cp.spawn(command, args, {
      stdio: 'inherit',
      shell: true,
    });

    // tslint:disable-next-line:no-any
    executedCommand.on('error', (error: any) => {
      reject(error);
    });

    executedCommand.on('exit', (code?: number) => {
      if (code === 0) {
        resolve();
      } else {
        reject();
      }
    });
  });
};

/**
 * @param {string} packageName name of the package
 * @returns {boolean} is the package installed?
 */
const isInstalled = (packageName: string) => {
  try {
    require.resolve(packageName);

    return true;
  } catch (err) {
    return false;
  }
};

/**
 * @typedef {Object} CliOption
 * @property {string} name display name
 * @property {string} package npm package name
 * @property {string} binName name of the executable file
 * @property {string} alias shortcut for choice
 * @property {boolean} installed currently installed?
 * @property {string} url homepage
 * @property {string} description description
 */

/** @type {CliOption[]} */
const CLIs = [
  {
    name: 'webpack-cli',
    package: 'webpack-cli',
    binName: 'webpack-cli',
    alias: 'cli',
    installed: isInstalled('webpack-cli'),
    url: 'https://github.com/webpack/webpack-cli',
    description: 'The original webpack full-featured CLI.',
  },
  {
    name: 'webpack-command',
    package: 'webpack-command',
    binName: 'webpack-command',
    alias: 'command',
    installed: isInstalled('webpack-command'),
    url: 'https://github.com/webpack-contrib/webpack-command',
    description: 'A lightweight, opinionated webpack CLI.',
  },
];

const installedClis = CLIs.filter(cli => cli.installed);

if (installedClis.length === 0) {
  const path = require('path');
  const fs = require('fs');
  const readLine = require('readline');

  let notify =
    // tslint:disable-next-line:max-line-length
    'One CLI for webpack must be installed. These are recommended choices, delivered as separate packages:';

  for (const item of CLIs) {
    notify += `\n - ${item.name} (${item.url})\n   ${item.description}`;
  }

  console.error(notify);

  const isYarn = fs.existsSync(path.resolve(process.cwd(), 'yarn.lock'));

  const packageManager = isYarn ? 'yarn' : 'npm';
  const installOptions = [isYarn ? 'add' : 'install', '-D'];

  console.error(
    // tslint:disable-next-line:max-line-length
    `We will use "${packageManager}" to install the CLI via "${packageManager} ${installOptions.join(
      ' ',
    )}".`,
  );

  const question = `Which one do you like to install (${CLIs.map(
    item => item.name,
  ).join('/')}):\n`;

  const questionInterface = readLine.createInterface({
    input: process.stdin,
    output: process.stderr,
  });
  questionInterface.question(question, (answer: string) => {
    questionInterface.close();

    const normalizedAnswer = answer.toLowerCase();
    const selectedPackage = CLIs.find(item => {
      return item.name === normalizedAnswer || item.alias === normalizedAnswer;
    });

    if (!normalizedAnswer) {
      console.error(
        'One CLI needs to be installed alongside webpack to use the CLI.',
      );
      process.exitCode = 1;

      return;
    } else if (!selectedPackage) {
      console.error(
        'No matching choice.\n' +
          'One CLI needs to be installed alongside webpack to use the CLI.\n' +
          'Try to installing your CLI of choice manually.',
      );
      process.exitCode = 1;

      return;
    }

    const packageName = selectedPackage.package;

    console.log(
      `Installing '${
        selectedPackage.name
      }' (running '${packageManager} ${installOptions.join(
        ' ',
      )} ${packageName}')...`,
    );

    runCommand(packageManager, installOptions.concat(packageName))
      .then(() => {
        require(`./udk-${packageName}`);
      })
      .catch(error => {
        console.error(error);
        process.exitCode = 1;
      });
  });
} else if (installedClis.length === 1) {
  if (installedClis[0].package === 'webpack-command') {
    require('./udk-webpack-command');
  } else {
    require('./udk-webpack-cli');
  }
} else {
  console.warn(
    `You have installed ${installedClis
      .map(item => item.name)
      // tslint:disable-next-line:max-line-length
      .join(' and ')} together. To work with the "webpack" command you need only one CLI package, please remove one of them or use them directly via their binary.`,
  );
}