From 33ffaef6de5d4f7de27ae40f55db919d22c6b84b Mon Sep 17 00:00:00 2001
From: Nicola Molinari <nicola.molinari@commercetools.com>
Date: Tue, 26 Apr 2022 15:00:07 +0200
Subject: [PATCH] fix(mc-scripts): dynamically change public path of assets on
 runtime for cdnUrl

---
 .../html-scripts/public-path.js               | 11 +++++++
 packages/mc-html-template/src/index.js        |  1 +
 .../mc-html-template/src/load-html-scripts.js |  1 +
 .../mc-html-template/src/process-headers.js   |  3 +-
 packages/mc-scripts/package.json              |  1 +
 .../mc-scripts/src/commands/build-vite.js     | 29 +++++++++++++++++--
 .../src/config/application-runtime.js         | 16 ++++++++--
 yarn.lock                                     | 17 +++++++++++
 8 files changed, 74 insertions(+), 5 deletions(-)
 create mode 100644 packages/mc-html-template/html-scripts/public-path.js

diff --git a/packages/mc-html-template/html-scripts/public-path.js b/packages/mc-html-template/html-scripts/public-path.js
new file mode 100644
index 0000000000..583eaddc02
--- /dev/null
+++ b/packages/mc-html-template/html-scripts/public-path.js
@@ -0,0 +1,11 @@
+window.__dynamicImportHandler__ = function (importer) {
+  return `${window.app.cdnUrl.replace(/\/$/, '')}/${importer.replace(
+    /^(\.\/)?/,
+    ''
+  )}`;
+};
+window.__dynamicImportPreload__ = function (preloads) {
+  return preloads.map(
+    (preload) => `${window.app.cdnUrl.replace(/\/$/, '')}/${preload}`
+  );
+};
diff --git a/packages/mc-html-template/src/index.js b/packages/mc-html-template/src/index.js
index 974bd78d7e..36ee4dda4a 100644
--- a/packages/mc-html-template/src/index.js
+++ b/packages/mc-html-template/src/index.js
@@ -2,3 +2,4 @@ exports.compileHtml = require('./compile-html');
 exports.generateTemplate = require('./generate-template');
 exports.processHeaders = require('./process-headers');
 exports.replaceHtmlPlaceholders = require('./utils/replace-html-placeholders');
+exports.htmlScripts = require('./load-html-scripts');
diff --git a/packages/mc-html-template/src/load-html-scripts.js b/packages/mc-html-template/src/load-html-scripts.js
index da4a619428..e8b6816f14 100644
--- a/packages/mc-html-template/src/load-html-scripts.js
+++ b/packages/mc-html-template/src/load-html-scripts.js
@@ -26,4 +26,5 @@ const loadScriptAsString = (fileName) => {
 module.exports = {
   dataLayer: loadScriptAsString('data-layer.js'),
   loadingScreen: loadScriptAsString('loading-screen.js'),
+  publicPath: loadScriptAsString('public-path.js'),
 };
diff --git a/packages/mc-html-template/src/process-headers.js b/packages/mc-html-template/src/process-headers.js
index da95d82bcd..7f16271f3c 100644
--- a/packages/mc-html-template/src/process-headers.js
+++ b/packages/mc-html-template/src/process-headers.js
@@ -46,11 +46,12 @@ const processHeaders = (applicationConfig) => {
   // List hashes for injected inline scripts.
   // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/script-src
   const htmlScriptsHashes = [
-    createAssetHash(htmlScripts.dataLayer),
     createAssetHash(htmlScripts.loadingScreen),
     createAssetHash(
       `window.app = ${sanitizeAppEnvironment(applicationConfig.env)};`
     ),
+    createAssetHash(htmlScripts.publicPath),
+    createAssetHash(htmlScripts.dataLayer),
   ];
 
   // // List hashes for injected inline styles.
diff --git a/packages/mc-scripts/package.json b/packages/mc-scripts/package.json
index eda6099a1f..676e698443 100644
--- a/packages/mc-scripts/package.json
+++ b/packages/mc-scripts/package.json
@@ -76,6 +76,7 @@
     "thread-loader": "3.0.4",
     "url": "^0.11.0",
     "vite": "2.9.1",
+    "vite-plugin-dynamic-publicpath": "1.1.2",
     "webpack": "5.72.0",
     "webpack-bundle-analyzer": "4.5.0",
     "webpack-dev-server": "4.8.1",
diff --git a/packages/mc-scripts/src/commands/build-vite.js b/packages/mc-scripts/src/commands/build-vite.js
index fa8edd6c42..fb13a8fd90 100644
--- a/packages/mc-scripts/src/commands/build-vite.js
+++ b/packages/mc-scripts/src/commands/build-vite.js
@@ -1,10 +1,13 @@
+/* eslint-disable react-hooks/rules-of-hooks */
 const fs = require('fs-extra');
 const path = require('path');
 const { build } = require('vite');
 const pluginGraphql = require('@rollup/plugin-graphql');
 const pluginReact = require('@vitejs/plugin-react').default;
+const { useDynamicPublicPath } = require('vite-plugin-dynamic-publicpath');
 const {
   generateTemplate,
+  htmlScripts,
 } = require('@commercetools-frontend/mc-html-template');
 const {
   packageLocation: applicationStaticAssetsPath,
@@ -23,10 +26,23 @@ const pluginCustomApplication = () => {
       // Ensure to use the `cdnUrl` value when loading the entry point.
       // NOTE: with Webpack this is done by setting the `__webpack_public_path__`.
       const html = rawHtml.replace(
-        new RegExp(`<script type="module"(.*) src="/(.*)">`, 'g'),
+        new RegExp(`<script type="module"(.*) src="(.*)">`, 'g'),
         `<script type="module"$1 src="__CDN_URL__$2">`
       );
-      return html;
+
+      return {
+        html,
+        tags: [
+          {
+            tag: 'script',
+            // Inject the functions to dynamically change the public path.
+            // This is also used for the `cdnUrl` and is the equivalent
+            // of Webpack's `__webpack_public_path__`.
+            children: htmlScripts.publicPath,
+            injectTo: 'body',
+          },
+        ],
+      };
     },
   };
 };
@@ -51,6 +67,7 @@ const execute = async () => {
   await build({
     configFile: false,
     root: paths.appRoot,
+    base: '', // <-- Very important, otherwise asset URLs start with `/`.
     define: {
       'process.env.DEBUG': JSON.stringify(false),
       'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV),
@@ -78,6 +95,14 @@ const execute = async () => {
         },
       }),
       pluginCustomApplication(),
+      // This plugin allows to change the public path on runtime.
+      // This is the equivalent of Webpack's `__webpack_public_path__`.
+      // See original issue: https://github.com/vitejs/vite/issues/3522#issuecomment-874377284
+      useDynamicPublicPath({
+        dynamicImportHandler: 'window.__dynamicImportHandler__',
+        dynamicImportPreload: 'window.__dynamicImportPreload__',
+        assetsBase: '.',
+      }),
     ],
   });
 
diff --git a/packages/mc-scripts/src/config/application-runtime.js b/packages/mc-scripts/src/config/application-runtime.js
index 35133a1b6b..b5d32b67bd 100644
--- a/packages/mc-scripts/src/config/application-runtime.js
+++ b/packages/mc-scripts/src/config/application-runtime.js
@@ -2,5 +2,17 @@
 // Dynamically inject webpack `publicPath`, for resolving assets locations.
 // https://webpack.js.org/guides/public-path/#on-the-fly
 // https://webpack.js.org/configuration/output/#output-publicpath
-if (process.env.NODE_ENV !== 'test')
-  __webpack_public_path__ = `${window.app.cdnUrl.replace(/\/$/, '')}/`;
+if (process.env.NODE_ENV !== 'test') {
+  const basePath = `${window.app.cdnUrl.replace(/\/$/, '')}/`;
+
+  // Webpack
+  __webpack_public_path__ = basePath;
+
+  // Vite
+  window.__dynamicImportHandler__ = function (importer) {
+    return basePath + importer;
+  };
+  window.__dynamicImportPreload__ = function (preloads) {
+    return preloads.map((preload) => basePath + preload);
+  };
+}
diff --git a/yarn.lock b/yarn.lock
index 661939fda9..d5d1f9e842 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3055,6 +3055,7 @@ __metadata:
     thread-loader: 3.0.4
     url: ^0.11.0
     vite: 2.9.1
+    vite-plugin-dynamic-publicpath: 1.1.2
     webpack: 5.72.0
     webpack-bundle-analyzer: 4.5.0
     webpack-dev-server: 4.8.1
@@ -16247,6 +16248,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"es-module-lexer@npm:^0.6.0":
+  version: 0.6.0
+  resolution: "es-module-lexer@npm:0.6.0"
+  checksum: ef04832d0f118e07c5aafc3824f274df380e9f86915a2d665884d9498f580b1f5607bc633504460a6c6247b7689aaa774b024d6733de28614d1fab72991a6fc3
+  languageName: node
+  linkType: hard
+
 "es-module-lexer@npm:^0.9.0":
   version: 0.9.3
   resolution: "es-module-lexer@npm:0.9.3"
@@ -34370,6 +34378,15 @@ __metadata:
   languageName: node
   linkType: hard
 
+"vite-plugin-dynamic-publicpath@npm:1.1.2":
+  version: 1.1.2
+  resolution: "vite-plugin-dynamic-publicpath@npm:1.1.2"
+  dependencies:
+    es-module-lexer: ^0.6.0
+  checksum: c631149bb006af3e5a6c00ef4cf891b33cc1e6d7839a5b940f671e798a8382196c5fe3a4782f047f7f37a65a76691a8e3c2eab62117be0a685f2287a32a47771
+  languageName: node
+  linkType: hard
+
 "vite@npm:2.9.1":
   version: 2.9.1
   resolution: "vite@npm:2.9.1"