webpack.config.js

const path = require("path");
const HtmlWebpackPlugin = require("html-webpack-plugin");
const { CleanWebpackPlugin } = require("clean-webpack-plugin");

module.exports = {
  entry: "./src/index.js",
  output: {
    path: path.resolve("dist"),
    filename: "bundle.js",
  },
  devtool: "inline-source-map",
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader",
          options: {
            presets: ["@babel/preset-env"],
            plugins: ["@babel/plugin-transform-react-jsx"],
          },
        },
      },
    ],
  },
  plugins: [
    // 在构建之前将dist文件夹清理掉
    new CleanWebpackPlugin({
      cleanOnceBeforeBuildPatterns: ["./dist"],
    }),
    // 指定HTML模板, 插件会将构建好的js文件自动插入到HTML文件中
    new HtmlWebpackPlugin({
      template: path.join(__dirname, "src/index.html"),
    }),
  ],
  devServer: {
    // 指定开发环境应用运行的根据目录
    contentBase: "./dist",
    // 指定控制台输出的信息
    stats: "errors-only",
    // 不启动压缩
    compress: false,
    host: "localhost",
    port: 3000,
  },
};