Webpack creating large file with small project

Question

I got my webpack generating a large main.js file (1.7mb) with a small project of ~20-30 files less than 100 lines each. The dependencies required are few in number (React, Fluxible) and I am using every optimize plugin I can understand:

module.exports = {
  output: {
    path: './build',
    publicPath: '/public/',
    filename: '[name].js'
  },
  debug: false,
  devtool: 'eval',
  target: 'web',
  entry: [
  'bootstrap-sass!./bootstrap-sass.config.js',
  './client.js',
  ],
  stats: {
    colors: true,
    reasons: false
  },
  resolve: {
    extensions: ['', '.js'],
    alias: {
      'styles': __dirname + '/src/styles',
      'components': __dirname + '/src/scripts/components',
      'actions': __dirname + '/src/scripts/actions',
      'stores': __dirname + '/src/scripts/stores',
      'constants': __dirname + '/src/scripts/constants',
      'mixins': __dirname + '/src/scripts/mixins',
      'configs': __dirname + '/src/scripts/configs',
      'utils': __dirname + '/src/scripts/utils'
    }
  },
  module: {
    loaders: [
      { test: /\.css$/, loader: 'style!css' },
      { test: /\.js$/, exclude: /node_modules/, loader: require.resolve('babel-loader') },
      { test: /\.json$/, loader: 'json-loader'},
      { test: /\.(png|svg|jpg)$/, loader: 'url-loader?limit=8192' },
      { test: /\.(ttf|eot|svg|woff|woff(2))(\?v=[0-9]\.[0-9]\.[0-9])?$/, loader: "url?name=/[name].[ext]"},
      { test: /\.scss$/,
        loader: ExtractTextPlugin.extract('style-loader',
          'css!sass?outputStyle=expanded&' +
          "includePaths[]=" +
          (path.resolve(__dirname, "./node_modules"))
          )
      }
    ]
  },
  plugins: [
    new webpack.NoErrorsPlugin(),
    new webpack.ProvidePlugin({
      $: "jquery",
      jQuery: "jquery",
      "windows.jQuery": "jquery"
    }),
    new ExtractTextPlugin("[name].css", {allChunks: true}),
    new webpack.optimize.DedupePlugin(),
    new webpack.optimize.UglifyJsPlugin(),
    new webpack.optimize.OccurenceOrderPlugin(),
    new webpack.optimize.AggressiveMergingPlugin()
  ],

};

What am I doing wrong or where can I further improve the size of the file?

Answer 1

I got my react down from 2.1mb down to 160kb gzipped just by doing the things here (devtools: 'source-map'), using uglifyjs with the default settings (without gzip it ends up being about 670kb).

It's probably not that great, but at least it's not crazy anymore.

For posterity, here is my webpack config:

// webpack.config.js
var webpack = require('webpack');

module.exports = {
    devtool: 'source-map',
    entry: [
        'webpack-dev-server/client?http://127.0.0.1:2992',
        'webpack/hot/only-dev-server',
        './js/main'
    ],
    output: {
        path: './out/',
        filename: 'main.js',
        chunkFilename: '[name]-[chunkhash].js',
        publicPath: 'http://127.0.0.1:2992/out/'
    },
    module: {
        loaders: [
            {
                test: /\.jsx?$/,
                exclude: /(node_modules|bower_components)/,
                loaders: ['react-hot', 'babel?optional=runtime&stage=0&plugins=typecheck']
            }
        ]
    },
    progress: true,
    resolve: {
        modulesDirectories: [
            'js',
            'node_modules'
        ],
        extensions: ['', '.json', '.js']
    },
    plugins: [
        new webpack.HotModuleReplacementPlugin(),
        new webpack.NoErrorsPlugin(),
        new webpack.IgnorePlugin(/^\.\/locale$/, /moment$/),
        new webpack.DefinePlugin({
            'process.env': {
                // This has effect on the react lib size
                'NODE_ENV': JSON.stringify('production'),
            }
        }),
        new webpack.optimize.UglifyJsPlugin()
    ]
};

Answer 2

You should set at least

plugins: [
  new webpack.DefinePlugin({
    'process.env': {
      // This has effect on the react lib size
      'NODE_ENV': JSON.stringify('production'),
    }
  }),
  ...
],

That will help considerably with React.

In addition setting devtool to source-map is preferable in production environment. See official documentation for more information.

You could try to inspect output using the analyse tool. To get the JSON it expects you'll need to do something like webpack --json > stats.json and then pass that stats.json to the tool. That might give you some insight.

Answer 3

You can also take a look at Webpack Bundle Analyzer.

It represents bundle content as convenient interactive zoomable treemap.