@enonic/react4xp/src/webpack.config.nashornPolyfills.ts

Build tools for React4xp

// Transpiles nashorn polyfill from, among other things, npm libraries.
// import type {Environment} from './index.d';


import {statSync} from 'fs';

import {isAbsolute, join, resolve} from 'path';

import {
	DIR_PATH_RELATIVE_BUILD_LIB_R4X,
	DIR_PATH_RELATIVE_SRC_MAIN_RESOURCES,
	FILE_NAME_R4X_NASHORN_POLYFILLS
} from './constants.buildtime';

import {makeVerboseLogger} from './util/makeVerboseLogger';
import webpackLogLevel, {R4X_BUILD_LOG_LEVEL, WEBPACK_STATS_LOG_LEVEL} from './util/webpackLogLevel';


const FILE_STEM_NASHORNPOLYFILLS_USERADDED = 'nashornPolyfills.userAdded';


export default (
	// env: Environment = {}
) => {
	const R4X_DIR_PATH_ABSOLUTE_PROJECT = process.env.R4X_DIR_PATH_ABSOLUTE_PROJECT;
	// console.debug('R4X_DIR_PATH_ABSOLUTE_PROJECT', R4X_DIR_PATH_ABSOLUTE_PROJECT);
	if (!isAbsolute(R4X_DIR_PATH_ABSOLUTE_PROJECT)) {
		throw new Error(`System environment variable R4X_DIR_PATH_ABSOLUTE_PROJECT:${R4X_DIR_PATH_ABSOLUTE_PROJECT} not an absolute path!`);
	}

	const DIR_PATH_ABSOLUTE_BUILD_SYSTEM = resolve(__dirname, '..');
	// console.debug('DIR_PATH_ABSOLUTE_BUILD_SYSTEM', DIR_PATH_ABSOLUTE_BUILD_SYSTEM);

	const DIR_PATH_ABSOLUTE_BUILD_LIB_R4X = join(R4X_DIR_PATH_ABSOLUTE_PROJECT, DIR_PATH_RELATIVE_BUILD_LIB_R4X);

	const WEBPACK_MODE = process.env.NODE_ENV || 'production';
	const DEVMODE = WEBPACK_MODE !== "production";
	const LOG_LEVEL = webpackLogLevel(process.env.R4X_BUILD_LOG_LEVEL as R4X_BUILD_LOG_LEVEL);

	const verboseLog = makeVerboseLogger([
		WEBPACK_STATS_LOG_LEVEL.LOG,
		WEBPACK_STATS_LOG_LEVEL.VERBOSE
	].includes(LOG_LEVEL));

	const filePathAbsoluteR4xNashornPolyfills = join(
		R4X_DIR_PATH_ABSOLUTE_PROJECT,
		DIR_PATH_RELATIVE_SRC_MAIN_RESOURCES,
		FILE_NAME_R4X_NASHORN_POLYFILLS
	);
	// verboseLog(filePathAbsoluteR4xNashornPolyfills, 'filePathAbsoluteR4xNashornPolyfills');

	const entry = {}
	try {
		const statsR4xNashornPolyfills = statSync(filePathAbsoluteR4xNashornPolyfills);
		if (statsR4xNashornPolyfills.isFile()) {
			verboseLog(
				`Adding custom nashorn polyfills: compiling ${filePathAbsoluteR4xNashornPolyfills} --> ${join(
					DIR_PATH_ABSOLUTE_BUILD_LIB_R4X, FILE_STEM_NASHORNPOLYFILLS_USERADDED)}`
			);
			entry[FILE_STEM_NASHORNPOLYFILLS_USERADDED] = filePathAbsoluteR4xNashornPolyfills;
		}
	} catch (e) {
		console.info(`${filePathAbsoluteR4xNashornPolyfills} not found, which is fine :)`)
	}

	const webpackConfigObjectNashornPolyfills = {
		context: R4X_DIR_PATH_ABSOLUTE_PROJECT, // Used as default for resolve.roots

		entry,

		mode: WEBPACK_MODE,

		module: {
			rules: [
				{
					test: /\.es6$/,

					// I don't think we can exclude much, everything must be able to run:
					// * server-side (Nashorn/Graal-JS) and
					// * client-side (Browsers).
					//exclude: /node_modules/,

					// It takes time to transpile, if you know they don't need
					// transpilation to run in Enonic XP (Nashorn/Graal-JS) you may list
					// them here:
					exclude: [
						/node_modules[\\/]core-js/, // will cause errors if they are transpiled by Babel
						/node_modules[\\/]webpack[\\/]buildin/ // will cause errors if they are transpiled by Babel
					],

					loader: 'builtin:swc-loader',
					options: {
						jsc: {
							// parser: {
							// 	syntax: 'typescript'
							// },

							// https://swc.rs/docs/configuration/compilation#jscexternalhelpers
							// externalHelpers: true,

							// `env` and `jsc.target` cannot be used together
							target: 'es2022', // Tested on "Graal" in Enonic 7.14.4

							transform: {
								// https://swc.rs/docs/configuration/compilation#jsctransformreact
								react: {
									runtime: 'automatic',
									development: DEVMODE,

									// $RefreshReg$ is not defined
									// refresh: DEVMODE,
									refresh: false,
								}
							}
						},
						// env: { // `env` and `jsc.target` cannot be used together
						// mode: 'usage',
						// coreJs: '3.26.1',
						// targets: 'Chrome >= 48',
						// }
					}
				},
			],
		}, // module

		optimization: {
			minimize: !DEVMODE
		},

		output: {
			path: DIR_PATH_ABSOLUTE_BUILD_LIB_R4X,

			filename: '[name].js', // No need for contenthash as this is serverside

			environment: {
				arrowFunction: false,
				bigIntLiteral: false,

				// Whether the environment supports const and let for variable declarations.
				const: false, // Not enough to transpile 'const' and 'let' to 'var'

				destructuring: false,
				dynamicImport: false,
				forOf: false,
				module: false,
				optionalChaining: true,
				templateLiteral: false
			},

			// In order for 'const' and 'let' to be transpiled to 'var',
			// library or libraryTarget must be set!

			//libraryTarget: 'commonjs' // 7963B
			//libraryTarget: 'commonjs-module' // 7870B // ReferenceError: 'module' is not defined
			libraryTarget: 'commonjs-static' // 7907B
			//libraryTarget: 'commonjs2' // 7870B // ReferenceError: 'module' is not defined

			/*library: {  // 7893B Trying out what is used in buildComponents, also transpiles 'const' and 'let' to 'var'
				name: '[name]',
				type: 'var',
			}*/

			// To make UMD build available on both browsers and Node.js, set output.globalObject option to 'this'.
			/*libraryTarget: 'umd', // 8111B
			globalObject: 'this'*/

			/*libraryTarget: 'umd2', // 8111B
			globalObject: 'this'*/
		}, // output

		resolve: {
			alias: {
				// Graalvm works with server-side version only!
				"html-dom-parser": [
					resolve(R4X_DIR_PATH_ABSOLUTE_PROJECT, 'node_modules/html-dom-parser/lib/server/html-to-dom.js'),
					resolve(DIR_PATH_ABSOLUTE_BUILD_SYSTEM, 'node_modules/html-dom-parser/lib/server/html-to-dom.js'),
				]
			},
			extensions: ['.ts', '.tsx', '.es6', '.es', '.jsx', '.js', '.json'],
			modules: [
				// Tell webpack what directories should be searched when resolving
				// modules.
				// Absolute and relative paths can both be used, but be aware that they
				// will behave a bit differently.
				// A relative path will be scanned similarly to how Node scans for
				// node_modules, by looking through the current directory as well as its
				// ancestors (i.e. ./node_modules, ../node_modules, and on).
				// With an absolute path, it will only search in the given directory.

				// To resolve node_modules installed under the app
				resolve(R4X_DIR_PATH_ABSOLUTE_PROJECT, 'node_modules'),

				// To resolve node_modules installed under the build system
				resolve(DIR_PATH_ABSOLUTE_BUILD_SYSTEM, 'node_modules'),
				//'node_modules'
			],
			/*roots: [ // Works, but maybe modules is more specific
				// A list of directories where requests of server-relative URLs
				// (starting with '/') are resolved, defaults to context configuration
				// option. On non-Windows systems these requests are resolved as an
				// absolute path first.
				R4X_DIR_PATH_ABSOLUTE_PROJECT, // same as context
				DIR_PATH_ABSOLUTE_BUILD_SYSTEM
			],*/
		}, // resolve

		stats: {
			colors: true,
			hash: false,
			logging: LOG_LEVEL,
			modules: false,
			moduleTrace: false,
			timings: false,
			version: false
		}, // stats

	}; // webpackConfigObjectNashornPolyfills
	//console.debug('webpackConfigObjectNashornPolyfills', webpackConfigObjectNashornPolyfills);
	return webpackConfigObjectNashornPolyfills;
};