webpack.config.js

const devCerts = require("office-addin-dev-certs");
const { CleanWebpackPlugin } = require("clean-webpack-plugin");
const CopyWebpackPlugin = require("copy-webpack-plugin");
const ExtractTextPlugin = require("extract-text-webpack-plugin");
const HtmlWebpackPlugin = require("html-webpack-plugin");
const webpack = require("webpack");
var dotenv = require("dotenv").config({ path: __dirname + "/.env" });

const urlDev = "https://localhost:3000/";
const urlProd = "https://www.contoso.com/"; // CHANGE THIS TO YOUR PRODUCTION DEPLOYMENT LOCATION

module.exports = async (env, options) => {
  const dev = options.mode === "development";
  const buildType = dev ? "dev" : "prod";
  const config = {
    devtool: "source-map",
    entry: {
      polyfill: ["core-js/stable", "regenerator-runtime/runtime"],
      vendor: ["react", "react-dom", "core-js", "@fluentui/react"],
      taskpane: ["react-hot-loader/patch", "./src/taskpane/index.tsx"],
      commands: "./src/commands/commands.ts",
    },
    resolve: {
      extensions: [".ts", ".tsx", ".html", ".js"],
    },
    module: {
      rules: [
        {
          test: /\.worker\.ts$/,
          loader: "worker-loader",
        },
        {
          test: /\.tsx?$/,
          use: ["react-hot-loader/webpack", "ts-loader"],
          exclude: /node_modules/,
        },
        {
          test: /\.css$/,
          use: ["style-loader", "css-loader"],
        },
        {
          test: /\.(png|jpg|jpeg|gif)$/,
          loader: "file-loader",
          options: {
            name: "[path][name].[ext]",
          },
        },
      ],
    },
    plugins: [
      new CleanWebpackPlugin(),
      new webpack.DefinePlugin({
        "process.env": JSON.stringify(dotenv.parsed),
      }),
      new CopyWebpackPlugin({
        patterns: [
          {
            to: "taskpane.css",
            from: "./src/taskpane/taskpane.css",
          },
          {
            to: "[name]." + buildType + ".[ext]",
            from: "manifest*.xml",
            transform(content) {
              if (dev) {
                return content;
              } else {
                return content.toString().replace(new RegExp(urlDev, "g"), urlProd);
              }
            },
          },
        ],
      }),
      new ExtractTextPlugin("[name].[hash].css"),
      new HtmlWebpackPlugin({
        filename: "taskpane.html",
        template: "./src/taskpane/taskpane.html",
        chunks: ["taskpane", "vendor", "polyfills"],
      }),
      // Needed as Azure deployment expects an index.html file
      new HtmlWebpackPlugin({
        filename: "index.html",
        template: "./src/index.html",
        chunks: ["index"],
      }),
      new HtmlWebpackPlugin({
        filename: "commands.html",
        template: "./src/commands/commands.html",
        chunks: ["commands"],
      }),
      new webpack.ProvidePlugin({
        Promise: ["es6-promise", "Promise"],
      }),
    ],
  };

  if (env.WEBPACK_SERVE) {
    config.devServer = {
      hot: true,
      headers: {
        "Access-Control-Allow-Origin": "*",
      },
      https:
        options.https !== undefined
          ? options.https
          : await devCerts.getHttpsServerOptions(),
      port: process.env.npm_package_config_dev_server_port || 3000,
    }
  }

  return config;
};