Add CORSWorkaround option + update isAbsoluteURL (#287)

* Fix isAbsoluteURL() regex

* Option to skip CORS workaround

Author: aminya

src/master/implementation.browser.ts

@@ -7,7 +7,7 @@ export const defaultPoolSize = typeof navigator !== "undefined" && navigator.har
   ? navigator.hardwareConcurrency
   : 4
 
-const isAbsoluteURL = (value: string) => /^(file|https?:)?\/\//i.test(value)
+const isAbsoluteURL = (value: string) => /^[a-zA-Z][a-zA-Z\d+\-.]*:/.test(value)
 
 function createSourceBlobURL(code: string): string {
   const blob = new Blob(
@@ -34,12 +34,16 @@ function selectWorkerImplementation(): ImplementationExport {
         url = new URL(url, options._baseURL)
       } else if (typeof url === "string" && !isAbsoluteURL(url) && getBundleURL().match(/^file:\/\//i)) {
         url = new URL(url, getBundleURL().replace(/\/[^\/]+$/, "/"))
-        url = createSourceBlobURL(`importScripts(${JSON.stringify(url)});`)
+        if (options?.CORSWorkaround ?? true) {
+          url = createSourceBlobURL(`importScripts(${JSON.stringify(url)});`)
+        }
       }
       if (typeof url === "string" && isAbsoluteURL(url)) {
         // Create source code blob loading JS file via `importScripts()`
         // to circumvent worker CORS restrictions
-        url = createSourceBlobURL(`importScripts(${JSON.stringify(url)});`)
+        if (options?.CORSWorkaround ?? true) {
+          url = createSourceBlobURL(`importScripts(${JSON.stringify(url)});`)
+        }
       }
       super(url, options)
     }

src/types/master.ts

@@ -81,8 +81,11 @@ export interface ThreadsWorkerOptions extends WorkerOptions {
     /** The size of a pre-allocated memory range used for generated code. */
     codeRangeSizeMb?: number
   }
-  /** Data passed on to Node worker_threads */
+  /** Data passed on to node.js worker_threads. */
   workerData?: any
+
+  /** Whether to apply CORS protection workaround. Defaults to true. */
+  CORSWorkaround?: boolean
 }
 
 /** Worker implementation. Either web worker or a node.js Worker class. */