feat: add ParagonWebpackPlugin to support design tokens

config/.eslintrc.js

@@ -39,6 +39,7 @@ module.exports = {
   },
   globals: {
     newrelic: false,
+    PARAGON_THEME: false,
   },
   ignorePatterns: [
     'module.config.js',

config/data/paragonUtils.js

@@ -0,0 +1,160 @@
+const path = require('path');
+const fs = require('fs');
+
+/**
+ * Attempts to extract the Paragon version from the `node_modules` of
+ * the consuming application.
+ *
+ * @param {string} dir Path to directory containing `node_modules`.
+ * @returns {string} Paragon dependency version of the consuming application
+ */
+function getParagonVersion(dir, { isBrandOverride = false } = {}) {
+  const npmPackageName = isBrandOverride ? '@openedx/brand' : '@openedx/paragon';
+  const pathToPackageJson = `${dir}/node_modules/${npmPackageName}/package.json`;
+  if (!fs.existsSync(pathToPackageJson)) {
+    return undefined;
+  }
+  return JSON.parse(fs.readFileSync(pathToPackageJson, 'utf-8')).version;
+}
+
+/**
+ * @typedef {Object} ParagonThemeCssAsset
+ * @property {string} filePath
+ * @property {string} entryName
+ * @property {string} outputChunkName
+ */
+
+/**
+ * @typedef {Object} ParagonThemeVariantCssAsset
+ * @property {string} filePath
+ * @property {string} entryName
+ * @property {string} outputChunkName
+ */
+
+/**
+ * @typedef {Object} ParagonThemeCss
+ * @property {ParagonThemeCssAsset} core The metadata about the core Paragon theme CSS
+ * @property {Object.<string, ParagonThemeVariantCssAsset>} variants A collection of theme variants.
+ */
+
+/**
+ * Attempts to extract the Paragon theme CSS from the locally installed `@openedx/paragon` package.
+ * @param {string} dir Path to directory containing `node_modules`.
+ * @param {boolean} isBrandOverride
+ * @returns {ParagonThemeCss}
+ */
+function getParagonThemeCss(dir, { isBrandOverride = false } = {}) {
+  const npmPackageName = isBrandOverride ? '@openedx/brand' : '@openedx/paragon';
+  const pathToParagonThemeOutput = path.resolve(dir, 'node_modules', npmPackageName, 'dist', 'theme-urls.json');
+
+  if (!fs.existsSync(pathToParagonThemeOutput)) {
+    return undefined;
+  }
+  const paragonConfig = JSON.parse(fs.readFileSync(pathToParagonThemeOutput, 'utf-8'));
+  const {
+    core: themeCore,
+    variants: themeVariants,
+    defaults,
+  } = paragonConfig?.themeUrls || {};
+
+  const pathToCoreCss = path.resolve(dir, 'node_modules', npmPackageName, 'dist', themeCore.paths.minified);
+  const coreCssExists = fs.existsSync(pathToCoreCss);
+
+  const themeVariantResults = Object.entries(themeVariants || {}).reduce((themeVariantAcc, [themeVariant, value]) => {
+    const themeVariantCssDefault = path.resolve(dir, 'node_modules', npmPackageName, 'dist', value.paths.default);
+    const themeVariantCssMinified = path.resolve(dir, 'node_modules', npmPackageName, 'dist', value.paths.minified);
+
+    if (!fs.existsSync(themeVariantCssDefault) && !fs.existsSync(themeVariantCssMinified)) {
+      return themeVariantAcc;
+    }
+
+    return ({
+      ...themeVariantAcc,
+      [themeVariant]: {
+        filePath: themeVariantCssMinified,
+        entryName: isBrandOverride ? `brand.theme.variants.${themeVariant}` : `paragon.theme.variants.${themeVariant}`,
+        outputChunkName: isBrandOverride ? `brand-theme-variants-${themeVariant}` : `paragon-theme-variants-${themeVariant}`,
+      },
+    });
+  }, {});
+
+  if (!coreCssExists || themeVariantResults.length === 0) {
+    return undefined;
+  }
+
+  const coreResult = {
+    filePath: path.resolve(dir, pathToCoreCss),
+    entryName: isBrandOverride ? 'brand.theme.core' : 'paragon.theme.core',
+    outputChunkName: isBrandOverride ? 'brand-theme-core' : 'paragon-theme-core',
+  };
+
+  return {
+    core: fs.existsSync(pathToCoreCss) ? coreResult : undefined,
+    variants: themeVariantResults,
+    defaults,
+  };
+}
+
+/**
+ * @typedef CacheGroup
+ * @property {string} type The type of cache group.
+ * @property {string|function} name The name of the cache group.
+ * @property {function} chunks A function that returns true if the chunk should be included in the cache group.
+ * @property {boolean} enforce If true, this cache group will be created even if it conflicts with default cache groups.
+ */
+
+/**
+ * @param {ParagonThemeCss} paragonThemeCss The Paragon theme CSS metadata.
+ * @returns {Object.<string, CacheGroup>} The cache groups for the Paragon theme CSS.
+ */
+function getParagonCacheGroups(paragonThemeCss) {
+  if (!paragonThemeCss) {
+    return {};
+  }
+  const cacheGroups = {
+    [paragonThemeCss.core.outputChunkName]: {
+      type: 'css/mini-extract',
+      name: paragonThemeCss.core.outputChunkName,
+      chunks: chunk => chunk.name === paragonThemeCss.core.entryName,
+      enforce: true,
+    },
+  };
+
+  Object.values(paragonThemeCss.variants).forEach(({ entryName, outputChunkName }) => {
+    cacheGroups[outputChunkName] = {
+      type: 'css/mini-extract',
+      name: outputChunkName,
+      chunks: chunk => chunk.name === entryName,
+      enforce: true,
+    };
+  });
+  return cacheGroups;
+}
+
+/**
+ * @param {ParagonThemeCss} paragonThemeCss The Paragon theme CSS metadata.
+ * @returns {Object.<string, string>} The entry points for the Paragon theme CSS. Example: ```
+ * {
+ *   "paragon.theme.core": "/path/to/node_modules/@openedx/paragon/dist/core.min.css",
+ *   "paragon.theme.variants.light": "/path/to/node_modules/@openedx/paragon/dist/light.min.css"
+ * }
+ * ```
+ */
+function getParagonEntryPoints(paragonThemeCss) {
+  if (!paragonThemeCss) {
+    return {};
+  }
+
+  const entryPoints = { [paragonThemeCss.core.entryName]: path.resolve(process.cwd(), paragonThemeCss.core.filePath) };
+  Object.values(paragonThemeCss.variants).forEach(({ filePath, entryName }) => {
+    entryPoints[entryName] = path.resolve(process.cwd(), filePath);
+  });
+  return entryPoints;
+}
+
+module.exports = {
+  getParagonVersion,
+  getParagonThemeCss,
+  getParagonCacheGroups,
+  getParagonEntryPoints,
+};

config/jest/setupTest.js

@@ -8,3 +8,38 @@ const testEnvFile = path.resolve(process.cwd(), '.env.test');
 if (fs.existsSync(testEnvFile)) {
   dotenv.config({ path: testEnvFile });
 }
+
+global.PARAGON_THEME = {
+  paragon: {
+    version: '1.0.0',
+    themeUrls: {
+      core: {
+        fileName: 'core.min.css',
+      },
+      defaults: {
+        light: 'light',
+      },
+      variants: {
+        light: {
+          fileName: 'light.min.css',
+        },
+      },
+    },
+  },
+  brand: {
+    version: '1.0.0',
+    themeUrls: {
+      core: {
+        fileName: 'core.min.css',
+      },
+      defaults: {
+        light: 'light',
+      },
+      variants: {
+        light: {
+          fileName: 'light.min.css',
+        },
+      },
+    },
+  },
+};

config/webpack.common.config.js

@@ -1,8 +1,35 @@
 const path = require('path');
+const RemoveEmptyScriptsPlugin = require('webpack-remove-empty-scripts');
+
+const ParagonWebpackPlugin = require('../lib/plugins/paragon-webpack-plugin/ParagonWebpackPlugin');
+const {
+  getParagonThemeCss,
+  getParagonCacheGroups,
+  getParagonEntryPoints,
+} = require('./data/paragonUtils');
+
+const paragonThemeCss = getParagonThemeCss(process.cwd());
+const brandThemeCss = getParagonThemeCss(process.cwd(), { isBrandOverride: true });
 
 module.exports = {
   entry: {
     app: path.resolve(process.cwd(), './src/index'),
+    /**
+     * The entry points for the Paragon theme CSS. Example: ```
+     * {
+     *   "paragon.theme.core": "/path/to/node_modules/@openedx/paragon/dist/core.min.css",
+     *   "paragon.theme.variants.light": "/path/to/node_modules/@openedx/paragon/dist/light.min.css"
+     * }
+     */
+    ...getParagonEntryPoints(paragonThemeCss),
+    /**
+     * The entry points for the brand theme CSS. Example: ```
+     * {
+     *   "paragon.theme.core": "/path/to/node_modules/@openedx/brand/dist/core.min.css",
+     *   "paragon.theme.variants.light": "/path/to/node_modules/@openedx/brand/dist/light.min.css"
+     * }
+     */
+    ...getParagonEntryPoints(brandThemeCss),
   },
   output: {
     path: path.resolve(process.cwd(), './dist'),
@@ -19,6 +46,23 @@ module.exports = {
     },
     extensions: ['.js', '.jsx', '.ts', '.tsx'],
   },
+  optimization: {
+    splitChunks: {
+      chunks: 'all',
+      cacheGroups: {
+        ...getParagonCacheGroups(paragonThemeCss),
+        ...getParagonCacheGroups(brandThemeCss),
+      },
+    },
+  },
+  plugins: [
+    // RemoveEmptyScriptsPlugin get rid of empty scripts generated by webpack when using mini-css-extract-plugin
+    // This helps to clean up the final bundle application
+    // See: https://www.npmjs.com/package/webpack-remove-empty-scripts#usage-with-mini-css-extract-plugin
+
+    new RemoveEmptyScriptsPlugin(),
+    new ParagonWebpackPlugin(),
+  ],
   ignoreWarnings: [
     // Ignore warnings raised by source-map-loader.
     // some third party packages may ship miss-configured sourcemaps, that interrupts the build

config/webpack.dev-stage.config.js

@@ -157,6 +157,7 @@ module.exports = merge(commonConfig, {
     new HtmlWebpackPlugin({
       inject: true, // Appends script tags linking to the webpack bundles at the end of the body
       template: path.resolve(process.cwd(), 'public/index.html'),
+      chunks: ['app'],
       FAVICON_URL: process.env.FAVICON_URL || null,
       OPTIMIZELY_PROJECT_ID: process.env.OPTIMIZELY_PROJECT_ID || null,
       NODE_ENV: process.env.NODE_ENV || null,