add polyfill for workers

elastic · Mar 14, 2024 · 4e4159e · 4e4159e
1 parent 1f22027
commit 4e4159e
Show file tree

Hide file tree

Showing 5 changed files with 42 additions and 8 deletions.
diff --git a/package.json b/package.json
@@ -1096,7 +1096,6 @@
     "remark-gfm": "1.0.0",
     "remark-parse-no-trim": "^8.0.4",
     "remark-stringify": "^8.0.3",
-    "remote-web-worker": "^0.0.9",
     "require-in-the-middle": "^7.2.1",
     "reselect": "^4.1.8",
     "resize-observer-polyfill": "1.5.1",

diff --git a/packages/kbn-monaco/BUILD.bazel b/packages/kbn-monaco/BUILD.bazel
@@ -30,7 +30,6 @@ SHARED_DEPS = [
   "@npm//monaco-editor",
   "@npm//monaco-yaml",
   "@npm//js-levenshtein",
-  "@npm//remote-web-worker",
 ]
 
 webpack_cli(

diff --git a/packages/kbn-monaco/src/register_globals.ts b/packages/kbn-monaco/src/register_globals.ts
@@ -6,7 +6,6 @@
  * Side Public License, v 1.
  */
 
-import 'remote-web-worker';
 import { XJsonLang } from './xjson';
 import { PainlessLang } from './painless';
 import { SQLLang } from './sql';

diff --git a/packages/kbn-ui-shared-deps-src/src/polyfills.js b/packages/kbn-ui-shared-deps-src/src/polyfills.js
@@ -17,3 +17,45 @@ if (typeof window.Event === 'object') {
 
 require('whatwg-fetch');
 require('symbol-observable');
+
+/**
+ * @description Adapted from https://github.com/jantimon/remote-web-worker/blob/main/src/index.ts
+ * with a modification to check that the requested worker url isn't already a blob, because of how workers are loaded for ace editor
+ */
+typeof window !== 'undefined' &&
+  // eslint-disable-next-line no-global-assign
+  (Worker = ((BaseWorker) =>
+    class Worker extends BaseWorker {
+      constructor(scriptURL, options) {
+        const url = String(scriptURL);
+        super(
+          // Check if the URL is remote
+          url.includes('://') && !url.startsWith(window.location.origin) && !url.startsWith('blob:') // to bootstrap the actual script to work around the same origin policy.
+            ? URL.createObjectURL(
+                new Blob(
+                  [
+                    // Replace the `importScripts` function with
+                    // a patched version that will resolve relative URLs
+                    // to the remote script URL.
+                    //
+                    // Without a patched `importScripts` Webpack 5 generated worker chunks will fail with the following error:
+                    //
+                    // Uncaught (in promise) DOMException: Failed to execute 'importScripts' on 'WorkerGlobalScope':
+                    // The script at 'http://some.domain/worker.1e0e1e0e.js' failed to load.
+                    //
+                    // For minification, the inlined variable names are single letters:
+                    // i = original importScripts
+                    // a = arguments
+                    // u = URL
+                    `importScripts=((i)=>(...a)=>i(...a.map((u)=>''+new URL(u,"${url}"))))(importScripts);importScripts("${url}")`,
+                  ],
+                  {
+                    type: 'text/javascript',
+                  }
+                )
+              )
+            : scriptURL,
+          options
+        );
+      }
+    })(Worker));
diff --git a/yarn.lock b/yarn.lock
@@ -26958,11 +26958,6 @@ remark-stringify@^8.0.3:
     unherit "^1.0.4"
     xtend "^4.0.1"
 
-remote-web-worker@^0.0.9:
-  version "0.0.9"
-  resolved "https://registry.yarnpkg.com/remote-web-worker/-/remote-web-worker-0.0.9.tgz#3a96a84063e6c1a5fa3792abe0fd97eb7a97aab3"
-  integrity sha512-TguJhQVWeeL2zWqLQpTfq/uIOpXRHHq7SI6fw6xTIJfSN/ojiKUqV16oAhPD8zH71MFy3FHqSoQEx2cks5gcAA==
-
 remove-accents@0.4.2:
   version "0.4.2"
   resolved "https://registry.yarnpkg.com/remove-accents/-/remove-accents-0.4.2.tgz#0a43d3aaae1e80db919e07ae254b285d9e1c7bb5"