custom sharedworker

packages/transport/src/sessions/background-browser.ts

@@ -2,6 +2,42 @@ import type { Descriptor } from '../types';
 import { SessionsBackground } from './background';
 import { HandleMessageParams, HandleMessageResponse, SessionsBackgroundInterface } from './types';
 
+class CustomSharedWorker extends SharedWorker {
+    constructor(scriptURL: string | URL, options?: WorkerOptions) {
+        const url = String(scriptURL);
+        super(
+            // Check if the URL is remote
+            url.includes('://') && !url.startsWith(location.origin)
+                ? // Launch the worker with an inline script that will use `importScripts`
+                  // 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,
+        );
+    }
+}
+
+export {};
 /**
  * creating BrowserSessionsBackground initiates sessions-background for browser based environments and provides:
  * - `handleMessage` which is used to send messages to sessions background
@@ -14,7 +50,7 @@ export class BrowserSessionsBackground implements SessionsBackgroundInterface {
     private readonly background;
 
     constructor(sessionsBackgroundUrl: string) {
-        this.background = new SharedWorker(sessionsBackgroundUrl, {
+        this.background = new CustomSharedWorker(sessionsBackgroundUrl, {
             name: '@trezor/connect-web transport sessions worker',
         });
     }