Modify GlobalRegistry to use async local storage to support multiple "global" containers

src/util/support/global.ts

@@ -1,18 +1,30 @@
 import {Collection} from '../collection/Collection'
 import {uuid4} from './data'
+import {AsyncLocalStorage} from 'async_hooks'
 
 /**
  * Type structure for a single item in the global registry.
  */
 export type GlobalRegistrant = { key: string | symbol, value: any }
 
+export class AccessGlobalRegistryOutsideAsyncLifecycleError extends Error {
+    constructor() {
+        super('Attempted to access global registry outside of an async context.')
+    }
+}
+
 /**
  * A convenient class to manage global variables.
  */
-export class GlobalRegistry extends Collection<GlobalRegistrant> {
-    constructor() {
-        super()
-        this.setGlobal('registry_uuid', uuid4())
+export class GlobalRegistry {
+    protected readonly storage: AsyncLocalStorage<Collection<GlobalRegistrant>> = new AsyncLocalStorage<Collection<GlobalRegistrant>>()
+
+    /** Run a closure with a global registry. */
+    public run<T>(closure: () => T): T {
+        return this.storage.run(new Collection<GlobalRegistrant>(), (): T => {
+            this.setGlobal('registry_uuid', uuid4())
+            return closure()
+        })
     }
 
     /**
@@ -21,11 +33,11 @@ export class GlobalRegistry extends Collection<GlobalRegistrant> {
      * @param value
      */
     public setGlobal(key: string | symbol, value: unknown): this {
-        const existing = this.firstWhere('key', '=', key)
+        const existing = this.getCollection().firstWhere('key', '=', key)
         if ( existing ) {
             existing.value = value
         } else {
-            this.push({
+            this.getCollection().push({
                 key,
                 value,
             })
@@ -39,7 +51,17 @@ export class GlobalRegistry extends Collection<GlobalRegistrant> {
      * @param key
      */
     public getGlobal(key: string | symbol): any {
-        return this.firstWhere('key', '=', key)?.value
+        return this.getCollection().firstWhere('key', '=', key)?.value
+    }
+
+    /** Get the globals collection or throw an error if outside async context. */
+    protected getCollection(): Collection<GlobalRegistrant> {
+        const coll = this.storage.getStore()
+        if ( !coll ) {
+            throw new AccessGlobalRegistryOutsideAsyncLifecycleError()
+        }
+
+        return coll
     }
 }