webpack.server.config.js

const path = require('path');
const glob = require('glob');
const R = require('ramda');
const {ProvidePlugin} = require('webpack');
const TerserPlugin = require('terser-webpack-plugin');
const {
  setEntriesForPath,
  addRule,
  addPlugin,
  prependExtensions
} = require('./util/compose');
const env = require('./util/env');

const RESOURCES_PATH = 'src/main/resources';

// ----------------------------------------------------------------------------
// Base config
// ----------------------------------------------------------------------------

const config = {
  context: path.join(__dirname, RESOURCES_PATH),
  entry: {},
  externals: [
    /^\/lib\/(.+|\$)$/i
  ],
  output: {
    path: path.join(__dirname, '/build/resources/main'),
    filename: '[name].js',
    libraryTarget: 'commonjs'
  },
  resolve: {
    extensions: [],
  },
  optimization: {
    minimizer: [
      new TerserPlugin({
        terserOptions: {
          compress: {
            drop_console: false,
          },
          keep_classnames: true,
          keep_fnames: true,
        }
      }),
    ],
    splitChunks: {
      minSize: 30000,
    },
  },
  mode: env.type,
  // Source maps are not usable in server scripts
  devtool: false,
};

// ----------------------------------------------------------------------------
// JavaScript loaders
// ----------------------------------------------------------------------------

function listEntries(extensions, ignoreList) {
  const CLIENT_FILES = glob.sync(`${RESOURCES_PATH}/assets/**/*.${extensions}`);
  const IGNORED_FILES = R.pipe(
    R.map(entry => path.join(RESOURCES_PATH, entry)),
    R.concat(CLIENT_FILES)
  )(ignoreList);
  const SERVER_FILES = glob.sync(`${RESOURCES_PATH}/**/*.${extensions}`, { absolute: false, ignore: IGNORED_FILES });
  return SERVER_FILES.map(entry => path.relative(RESOURCES_PATH, entry));
}

// TYPESCRIPT
function addTypeScriptSupport(cfg) {
  const rule = {
    test: /\.ts$/,
    exclude: /node_modules/,
    loader: 'ts-loader',
    options: {
      configFile: 'src/main/resources/tsconfig.server.json',
    }
  };

  const entries = listEntries('ts', [
    // Add additional files to the ignore list.
    // The following path will be transformed to 'src/main/resources/types.ts:
    'types.ts'
  ]).filter(entry => entry.indexOf('.d.ts') === -1);

  return R.pipe(
    setEntriesForPath(entries),
    addRule(rule),
    addPlugin(new ProvidePlugin({
      'Object.assign': [path.join(__dirname, RESOURCES_PATH, 'polyfills'), 'assign']
    })),
    prependExtensions(['.ts', '.json'])
  )(cfg);
}

// BABEL
function addBabelSupport(cfg) {
  const rule = {
    test: /\.(es6?|js)$/,
    exclude: /node_modules/,
    loader: 'babel-loader',
    options: {
      babelrc: false,
      plugins: [],
      presets: [
        [
          '@babel/preset-env',
          {
            // Use custom Browserslist config
            targets: 'node 0.10',
            // Polyfills are not required in runtime
            useBuiltIns: false
          },
        ],
      ]
    }
  };

  const entries = listEntries('{js,es,es6}', [
    // Add additional files to the ignore list.
    // The following path will be transformed to 'src/main/resources/lib/observe/observe.es6':
    'lib/observe/observe.es6'
  ]);

  return R.pipe(
    setEntriesForPath(entries),
    addRule(rule),
    prependExtensions(['.js', '.es', '.es6', '.json'])
  )(cfg);
}

// ----------------------------------------------------------------------------
// Result config
// ----------------------------------------------------------------------------

module.exports = R.pipe(
  addBabelSupport,
  addTypeScriptSupport
)(config);