From e54ce29a29d178b0ddbe4a74ff794ede7c03a31d Mon Sep 17 00:00:00 2001
From: Jack Westbrook <jack.westbrook@gmail.com>
Date: Tue, 3 Dec 2024 17:23:04 +0100
Subject: [PATCH] refactor(crash): clean up cors sharedworker

---
 public/app/core/crash/index.ts            |  5 ++-
 public/app/core/utils/CorsSharedWorker.ts | 38 ++++++-----------------
 public/app/core/utils/CorsWorker.ts       |  2 +-
 3 files changed, 13 insertions(+), 32 deletions(-)

diff --git a/public/app/core/crash/index.ts b/public/app/core/crash/index.ts
index 929ff7ef7e4..79e64e2b2fb 100644
--- a/public/app/core/crash/index.ts
+++ b/public/app/core/crash/index.ts
@@ -6,7 +6,7 @@ import { config, createMonitoringLogger } from '@grafana/runtime';
 import { corsWorker } from 'app/core/utils/CorsWorker';
 
 import { contextSrv } from '../services/context_srv';
-import { CorsSharedWorker as SharedWorker, sharedWorkersSupported } from '../utils/CorsSharedWorker';
+import { corsSharedWorker, sharedWorkersSupported } from '../utils/CorsSharedWorker';
 
 import { isChromePerformance, prepareContext } from './crash.utils';
 
@@ -61,8 +61,7 @@ export function initializeCrashDetection() {
      *  We guarantee the type assertion is correct by returning a SharedWorker in CorsSharedWorker constructor.
      */
     createDetectorWorker() {
-      // eslint-disable-next-line @typescript-eslint/consistent-type-assertions
-      return new SharedWorker(new URL('./detector.worker', import.meta.url)) as globalThis.SharedWorker;
+      return corsSharedWorker('./detector.worker', { name: 'crashDetector' });
     },
 
     reportCrash: async (report) => {
diff --git a/public/app/core/utils/CorsSharedWorker.ts b/public/app/core/utils/CorsSharedWorker.ts
index 6edee786867..c9a6c549b65 100644
--- a/public/app/core/utils/CorsSharedWorker.ts
+++ b/public/app/core/utils/CorsSharedWorker.ts
@@ -1,33 +1,15 @@
-// Almost identical to CorsWorker.ts. Main difference being it allows loading a SharedWorker if browser supports it
-
 export function sharedWorkersSupported() {
   return typeof window.SharedWorker !== 'undefined';
 }
 
-/**
- * Creating CorsSharedWorker should be called only if sharedWorkersSupported() is truthy
- */
-export class CorsSharedWorker {
-  constructor(url: URL, options?: WorkerOptions) {
-    if (!sharedWorkersSupported()) {
-      throw new Error('SharedWorker is not supported');
-    }
-    // by default, worker inherits HTML document's location and pathname which leads to wrong public path value
-    // the CorsWorkerPlugin will override it with the value based on the initial worker chunk, ie.
-    //    initial worker chunk: http://host.com/cdn/scripts/worker-123.js
-    //    resulting public path: http://host.com/cdn/scripts
-
-    const scriptUrl = url.toString();
-    const scriptsBasePathUrl = new URL('.', url).toString();
-
-    const importScripts = `importScripts('${scriptUrl}');`;
-    const objectURL = URL.createObjectURL(
-      new Blob([`__webpack_worker_public_path__ = '${scriptsBasePathUrl}'; ${importScripts}`], {
-        type: 'application/javascript',
-      })
-    );
-    const worker = new SharedWorker(objectURL, options);
-    URL.revokeObjectURL(objectURL);
-    return worker;
-  }
+// This function is used to create a sharedworker that can load across domains.
+export function corsSharedWorker(workerUrl: string, options: WorkerOptions) {
+  const js = `import ${JSON.stringify(new URL(workerUrl, import.meta.url))}`;
+  const blob = new Blob([js], { type: 'application/javascript' });
+  const objURL = URL.createObjectURL(blob);
+  const worker = new SharedWorker(objURL, { type: 'module', name: options?.name });
+  worker.addEventListener('error', (e) => {
+    URL.revokeObjectURL(objURL);
+  });
+  return worker;
 }
diff --git a/public/app/core/utils/CorsWorker.ts b/public/app/core/utils/CorsWorker.ts
index ef71e918cb5..b9bfa56cdc7 100644
--- a/public/app/core/utils/CorsWorker.ts
+++ b/public/app/core/utils/CorsWorker.ts
@@ -1,4 +1,4 @@
-// This function is used to create a worker that can be used to fetch data from a different domain (e.g. CDN).
+// This function is used to create a worker that can load across domains.
 export function corsWorker(workerUrl: string, options: WorkerOptions) {
   const js = `import ${JSON.stringify(new URL(workerUrl, import.meta.url))}`;
   const blob = new Blob([js], { type: 'application/javascript' });