DllPlugin and DllReferencePlugin

Introduction#

The Dll and DllReference plugins allow the code to be split in multiple bundles in a way the bundles can be compiled independently.

It is possible to build “vendor” scripts in a library that does not need to be compiled often (ex: React, jQuery, Bootstrap, Fontawesome…) and reference it in your app bundle that will need those scripts.

The application bundle, the one that is constantly going to be changed, will be in a separate configuration just referencing a already built “vendor” bundle.

Syntax#

new webpack.DllPlugin({ path: ‘[name]-manifest.json’, name: ‘[name]_[hash]’ })
new webpack.DllReferencePlugin({ context: __dirname, manifest: require(‘./packname-manifest.json’) })

Vendor configuration (DllPlugin)

Note: The output.library and name (in DllPlugin) must be the same.

const path = require('path');
const webpack = require('webpack');
const ExtractTextPlugin = require('extract-text-webpack-plugin');
const extractCSS = new ExtractTextPlugin('vendor.css');
const isDevelopment = process.env.NODE_ENV !== 'production';

module.exports = {
  resolve: {
    extensions: ['.js'],
  },
  module: {
    rules: [
      { test: /\.(png|woff|woff2|eot|ttf|svg)$/, loader: 'url-loader?limit=100000' },
      { test: /\.s?css$/i, loader: extractCSS.extract(['css-loader?minimize', 'sass-loader']) },
      { test: /\.json$/, loader: 'json-loader' },
    ],
  },
  entry: {
    vendor: [
      'babel-polyfill',
      'font-awesome/scss/font-awesome.scss',
      'bootstrap/scss/bootstrap.scss',
      'jquery',
      'history',
      'react',
      'react-dom',
      'redux',
      'react-redux',
      'react-router',
      'react-router-dom',
      'react-router-redux',
      'redux-thunk',
    ],
  },
  output: {
    path: path.resolve('./dist'),
    filename: '[name].js',
    library: '[name]_[hash]',
  },
  plugins: [
    extractCSS,
    new webpack.DllPlugin({
      path: path.join(__dirname, 'dist', '[name]-manifest.json'),
      name: '[name]_[hash]',
    })
  ].concat(isDevelopment ? [] : [
    new webpack.optimize.UglifyJsPlugin({
      beautify: false,
      comments: false,
    }),
  ]),
};

Referencing a Dll Bundle (DllReferencePlugin)

Note: manifest (in DllReferencePlugin) should reference path (defined in DllPlugin)

const webpack = require('webpack');
const path = require('path');
const isDevelopment = process.env.NODE_ENV !== 'production';

const ExtractTextPlugin = require('extract-text-webpack-plugin');
const extractCSS = new ExtractTextPlugin('app.css');

const merge = require('extendify')({ isDeep: true, arrays: 'concat' });

module.exports = merge({
  context: __dirname,
  entry: {
    app: (isDevelopment ? ['webpack-hot-middleware/client'] : []).concat(['./src/']),
  },
  output: {
    path: path.resolve('./dist'),
    publicPath: '/static',
    filename: '[name].js',
  },
  resolve: {
    extensions: ['.js', '.ts', '.tsx'],
  },
  module: {
    loaders: [
      {
        test: /\.tsx?$/,
        loader: 'babel-loader!awesome-typescript-loader?forkChecker=true',
        include: /src|spec/,
      },
      {
        test: /\.s?css$/,
        loader: extractCSS.extract(['css-loader?minimize', 'sass-loader']),
        include: /src/,
      },
    ],
  },
  plugins: [
    new webpack.DllReferencePlugin({
      context: __dirname,
      manifest: require('./dist/vendor-manifest.json'),
    }),
    new webpack.DefinePlugin({
      'process.env': {
        'ENV': JSON.stringify(process.env.NODE_ENV),
      },
    }),
    extractCSS,
  ],
}, isDevelopment ? require('./webpack.config.development') : require('./webpack.config.production'));