webpack.prod.config.js

var path = require("path")
var webpack = require('webpack')
var BundleTracker = require('webpack-bundle-tracker')
var CompressionPlugin = require('compression-webpack-plugin')

module.exports = {
  context: __dirname,

  entry: './assets/js/index', // entry point of our app. assets/js/index.js should require other js modules and dependencies it needs

  output: {
      path: path.resolve('./assets/bundles/'),
      filename: "[name]-[hash].js"
  },

  plugins: [
    new BundleTracker({filename: './webpack-stats.json'}),

    // removes a lot of debugging code in React
    new webpack.DefinePlugin({
      'process.env': {
        'NODE_ENV': JSON.stringify('production')
    }}),

    // keeps hashes consistent between compilations
    new webpack.optimize.AggressiveMergingPlugin(),
    new webpack.optimize.OccurrenceOrderPlugin(),
    new webpack.optimize.DedupePlugin(),
    new webpack.optimize.UglifyJsPlugin({
      minimize : true,
      mangle: true,
      compress: {
        warnings: false, // Suppress uglification warnings
        pure_getters: true,
        unsafe: true,
        unsafe_comps: true,
        screw_ie8: true
      },
      output: {
        comments: false,
      },
      exclude: [/\.min\.js$/gi] // skip pre-minified libs
    }),

    new webpack.IgnorePlugin(/^\.\/locale$/, [/moment$/]),

    new CompressionPlugin({
      asset: "[path].gz[query]",
      algorithm: "gzip",
      test: /\.js$|\.css$|\.html$/,
      threshold: 10240,
      minRatio: 0.8,
      deleteOriginalAssets: true,
    })
  ],

  module: {
    loaders: [
      { test: /\.jsx?$/,
        exclude: /node_modules/,
        loader: 'babel-loader', // to transform JSX into JS
        query:
        {
          presets:['react', 'es2015', 'stage-1']
        }
      }
    ],
  },

  resolve: {
    modulesDirectories: ['node_modules', 'bower_components'],
    extensions: ['', '.js', '.jsx']
  },
}