webpack.config.js

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

module.exports = {
  mode: 'development',
  entry: path.join(__dirname, "src", "index.js"),
  output: {
    path:path.resolve(__dirname, "public"),
  },
  devServer: {
    static: {
      directory: path.resolve(__dirname, 'public'),
    },
    port: 3000,
    open: true,
    hot: true,
    compress: true,
    historyApiFallback: true,
    allowedHosts: "all",
  },
  module: {
    rules: [
      {
        test: /\.?js$/,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader",
          options: {
            presets: ['@babel/preset-env', '@babel/preset-react']
          }
        },
      },
      {
        test: /\.css$/i,
        include: path.resolve(__dirname, 'src'),
        use: ['style-loader', 'css-loader', 'postcss-loader'],
      },
      {
        test: /\.s[ac]ss$/i,
        use: [
          // Creates `style` nodes from JS strings
          "style-loader",
          // Translates CSS into CommonJS
          "css-loader",
          // Compiles Sass to CSS
          "postcss-loader",
          "sass-loader",
        ],
      },
    ]
  },
  plugins: [
    new HtmlWebpackPlugin({
      template: path.join(__dirname, "src", "index.html"),
    }),
    new Dotenv(),
  ],
  resolve: {
    fallback: {
      "os": require.resolve("os-browserify/browser"),
      "fs": false,
      "process": require.resolve("process/browser")
    }
  }
}