webpack.config.js

const path = require('path');
const webpack = require('webpack');
const UglifyJsPlugin = require('uglifyjs-webpack-plugin');
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;

module.exports = {
    entry: {
        app: './src/app.js'
    },
    output: {
        path: path.join(__dirname, 'public'),
        filename: '[name].js'
    },
    resolve: {
        alias: {
            '@material-ui/core': '@material-ui/core/es',
            '@material-ui/icons': '@material-ui/icons/es'
        }
    },
    plugins: [
        new webpack.DefinePlugin({
            'process.env': {
                'NODE_ENV': JSON.stringify('production')
            }
        }),
        // new BundleAnalyzerPlugin(),
        new UglifyJsPlugin({
            test: /\.js($|\?)/i,
            sourceMap: true
        })
    ],
    optimization: {
        splitChunks: {
            cacheGroups: {
                commons: {
                    test: /[\\/]node_modules[\\/]/,
                    name: "vendors",
                    chunks: "all"
                }
            }
        }
    },
    module: {
        rules: [{
            loader: 'babel-loader',
            test: /\.js$/,
            exclude: /node_modules/
        }, {
            test: /\.s?css$/,
            use: [
                'style-loader',
                'css-loader',
                'sass-loader'
            ]
        }]
    },
    devtool: 'cheap-module-eval-source-map',
    devServer: {
        contentBase: path.join(__dirname, 'public'),
        host: "localhost",
        proxy: {
            '/app.js': {
                target: 'http://localhost:8080'
            },
            '/vendors.js': {
                target: 'http://localhost:8080'
            },
            '/**': {
                target: 'http://localhost:4000',
                secure: false,
                changeOrigin: true
            }
        }
    }
};