webpack.config.js

const path = require('path');
const webpack = require('webpack');
const autoprefixer = require('autoprefixer');
const cssnano = require('cssnano');
const HTMLWebpackPlugin = require('html-webpack-plugin');
const uglifyJsPlugin = require('uglifyjs-webpack-plugin');
const CopyWebpackPlugin = require('copy-webpack-plugin');
const MiniCssExtractPlugin = require("mini-css-extract-plugin");

module.exports = {
    entry: ['babel-polyfill', './src/app.js'],
    output: {
        library: 'UserList',
        libraryTarget: 'umd',
        libraryExport: 'default',
        path: path.resolve(__dirname, 'dist'),
        filename: 'bundle.js',
        publicPath: '',
    },
    devtool: 'cheap-module-eval-source-map',
    module: {
        rules: [{
                test: /\.js$/,
                exclude: /node_modules/,
                use: ['babel-loader']
            },
            {
                test: /\.(scss|css)$/,
                use: [
                    MiniCssExtractPlugin.loader,
                    {
                        loader: "css-loader",
                        options: {
                            minimize: {
                                safe: true
                            }
                        }
                    },
                    {
                        loader: "postcss-loader",
                        options: {
                            autoprefixer: {
                                browsers: ["last 2 versions"]
                            },
                            plugins: () => [
                                autoprefixer,
                                cssnano
                            ]
                        },
                    },
                    {
                        loader: "sass-loader",
                        options: {}
                    }
                ]
            },
            {
                test: /\.txt$/,
                use: 'raw-loader'
            }
        ]
    },
    plugins: [
        new uglifyJsPlugin({ 
            sourceMap: true,
            uglifyOptions: {
                output: {
                    comments: false,
                    beautify: false
                }
            }
        }),
        new MiniCssExtractPlugin({
            filename: 'bundle.css',
        }),
        new HTMLWebpackPlugin({
            template: path.resolve(__dirname, 'index.html')
        }),
        new webpack.HotModuleReplacementPlugin(),
        new CopyWebpackPlugin([{
            from: 'src/assets',
            to: 'assets'
        }]),
        // new webpack.SourceMapDevToolPlugin({})
    ]
};