webpack.config.js

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const webpack = require('webpack');

const config = {
    entry: ['babel-polyfill', 'whatwg-fetch', './app/index.js'],
    output: {
        path: path.resolve(__dirname, 'dist'),
        filename: 'index_bundle.js',
        publicPath: '/'
    },
    module:{
        rules: [
            {test: /\.(js)$/, use: 'babel-loader'},
            {test: /\.css$/, use: ['style-loader', 'css-loader']}
        ]
    },
    devServer: {
      historyApiFallback: true
    },
    plugins: [new HtmlWebpackPlugin({
        template: 'app/index.html'
    })]
}

if(process.env.NODE_ENV === 'production') {
  config.plugins.push(
    new webpack.DefinePlugin({
      'process.env': {
        'NODE_ENV': JSON.stringify(process.env.NODE_ENV)
      }
    }),
    new webpack.optimize.UglifyJsPlugin()
  )
}

module.exports = config;