webpack.js

const path = require("path");
const { CleanWebpackPlugin } = require("clean-webpack-plugin");
const CopyWebpackPlugin = require('copy-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const CssMinimizerPlugin = require('css-minimizer-webpack-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const PreloadWebpackPlugin = require('@vue/preload-webpack-plugin');
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;

const plugins = [
  new CleanWebpackPlugin({}),

  new MiniCssExtractPlugin({
    filename: '[name].[contenthash].css'
  }),

  new HtmlWebpackPlugin({
    template: 'public/index.html'
  }),

  new PreloadWebpackPlugin({
    rel: 'preload',
    include: 'all'
  }),

  new CopyWebpackPlugin({
    patterns: [{
      from: path.resolve(__dirname, 'public', 'assets'),
      to: path.resolve(__dirname, 'dist', 'assets')
    }]
  })
]

if (process.env.BUNDLE_ANALYZE) {
  plugins.push(new BundleAnalyzerPlugin())
}

module.exports = {
  mode: "development",
  entry: {
    main: "./src/index.js",
  },
  output: {
    filename: "[name].[contenthash].js",
    path: path.resolve(__dirname, "dist")
  },
  devServer: {
    historyApiFallback: true,
    disableHostCheck: true,
    stats: "minimal",
    contentBase: path.join(__dirname, 'public'),
    compress: true,
    open: true,
    hot: true
  },
  target: 'web',
  resolve: {
    fallback: {
      "os": false
    }
  },
  module: {
    rules: [
      {
        test: /\.m?js$/,
        exclude: /(node_modules|bower_components)/,
        use: {
          loader: 'babel-loader',
          options: require("./.babelrc")
        }
      },
      {
        test: /\.css$/,
        use: [
          {
            loader: MiniCssExtractPlugin.loader
          },
          'css-loader',
          'postcss-loader'
        ]
      }
    ]
  },
  optimization: {
    minimizer: [
      new CssMinimizerPlugin(),
    ],
  },
  externals: {
    firebase: 'firebase',
  },
  plugins
};