Merge pull request #33782 from UsainBloot/feat/extension-point-middleware

feat(backend): add extensionPointFactoryMiddleware to createBackend

packages/backend-defaults/report.api.md

@@ -5,10 +5,14 @@
 ```ts
 import { Backend } from '@backstage/backend-app-api';
 import { BackendFeature } from '@backstage/backend-plugin-api';
+import { ServiceFactory } from '@backstage/backend-plugin-api';
 
 // @public (undocumented)
 export function createBackend(): Backend;
 
+// @public (undocumented)
+export const defaultServiceFactories: ServiceFactory[];
+
 // @public
 export const discoveryFeatureLoader: BackendFeature;
 ```

packages/backend-defaults/src/CreateBackend.ts

@@ -15,6 +15,7 @@
  */
 
 import { Backend, createSpecializedBackend } from '@backstage/backend-app-api';
+import { ServiceFactory } from '@backstage/backend-plugin-api';
 import { auditorServiceFactory } from '@backstage/backend-defaults/auditor';
 import { authServiceFactory } from '@backstage/backend-defaults/auth';
 import { cacheServiceFactory } from '@backstage/backend-defaults/cache';
@@ -42,7 +43,8 @@ import {
 } from '@backstage/backend-defaults/alpha';
 import { instanceMetadataServiceFactory } from './alpha/entrypoints/instanceMetadata/instanceMetadataServiceFactory';
 
-export const defaultServiceFactories = [
+/** @public */
+export const defaultServiceFactories: ServiceFactory[] = [
   auditorServiceFactory,
   authServiceFactory,
   cacheServiceFactory,

packages/backend-defaults/src/index.ts

@@ -20,5 +20,5 @@
  * @packageDocumentation
  */
 
-export { createBackend } from './CreateBackend';
+export { createBackend, defaultServiceFactories } from './CreateBackend';
 export { discoveryFeatureLoader } from './discoveryFeatureLoader';