webpack.config.js

var webpack = require("webpack"),
  path = require("path"),
  fileSystem = require("fs"),
  env = require("./utils/env"),
  { CleanWebpackPlugin } = require("clean-webpack-plugin"),
  CopyWebpackPlugin = require("copy-webpack-plugin"),
  HtmlWebpackPlugin = require("html-webpack-plugin"),
  WriteFilePlugin = require("write-file-webpack-plugin"),
  MiniCssExtractPlugin = require("mini-css-extract-plugin"),
  TerserPlugin = require('terser-webpack-plugin');
// load the secrets
var alias = {};

var secretsPath = path.join(__dirname, "secrets." + env.NODE_ENV + ".js");

var fileExtensions = [
  "jpg",
  "jpeg",
  "png",
  "gif",
  "eot",
  "otf",
  "svg",
  "ttf",
  "woff",
  "woff2"
];

if (fileSystem.existsSync(secretsPath)) {
  alias["secrets"] = secretsPath;
}

var options = {
  mode: env.NODE_ENV,
  entry: {
    popup: path.join(__dirname, "src", "js", "popup.js"),
    background: path.join(__dirname, "src", "js", "background.js"),
    importfile: path.join(__dirname, "src", "js", "importfile.js")
  },
  output: {
    path: path.join(__dirname, "build"),
    filename: "[name].bundle.js"
  },
  optimization: {
    minimizer: [
      new TerserPlugin({
        extractComments: false,
        cache: true,
        parallel: true,
        terserOptions: {
          compress: {
              drop_console: true,
          },
        }
      }),
    ],
  },
  module: {
    rules: [
      {
        test: /\.(js|svelte)$/,
        loader: "eslint-loader",
        enforce: "pre",
        include: [path.join(__dirname, "..", "src")],
        options: {
          formatter: require("eslint-friendly-formatter")
        }
      },
      {
        test: /\.(sa|sc|c)ss$/,
        use: [
          "style-loader",
          MiniCssExtractPlugin.loader,
          "css-loader",
          {
            loader: "sass-loader",
            options: {
              sassOptions: {
                includePaths: ["./theme", "./node_modules"]
              }
            }
          }
        ]
      },
      {
        test: new RegExp(".(" + fileExtensions.join("|") + ")$"),
        loader: "file-loader?name=[name].[ext]",
        exclude: /node_modules/
      },
      {
        test: /\.html$/,
        loader: "html-loader",
        exclude: /node_modules/
      },
      {
        test: /\.svelte$/,
        use: {
          loader: "svelte-loader",
          options: {
            emitCss: false,
            hotReload: false
          }
        }
      }
    ]
  },
  resolve: {
    alias: alias
  },
  plugins: [
    // clean the build folder
    new CleanWebpackPlugin({
      cleanStaleWebpackAssets: false,
      cleanOnceBeforeBuildPatterns: [path.join(__dirname, "build")]
    }),
    new MiniCssExtractPlugin(),
    // expose and write the allowed env vars on the compiled bundle
    new webpack.DefinePlugin({
      "process.env.NODE_ENV": JSON.stringify(env.NODE_ENV),
      "process.env.BROWSER": JSON.stringify(env.BROWSER),
    }),
    new CopyWebpackPlugin([
      {
        from: "src/manifest.json",
        transform: function (content, path) {
          // generates the manifest file using the package.json informations
          const manifest = JSON.parse(content.toString());
          return Buffer.from(
            JSON.stringify({
              description: process.env.npm_package_description,
              version: process.env.npm_package_version,
              ...manifest
            })
          );
        }
      },
      {
        from: "src/images",
        to: "images"
      }
    ]),
    new HtmlWebpackPlugin({
      template: path.join(__dirname, "src", "popup.html"),
      filename: "popup.html",
      chunks: ["popup"]
    }),
    new HtmlWebpackPlugin({
      template: path.join(__dirname, "src", "importfile.html"),
      filename: "importfile.html",
      chunks: ["importfile"]
    }),
    new WriteFilePlugin()
  ]
};

module.exports = options;