feat: add an instance metadata experimental service

Signed-off-by: aramissennyeydd <aramis.sennyey@doordash.com>

packages/backend-plugin-api/src/services/definitions/InstanceMetadataService.ts

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2024 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+export type BackendFeatureMeta =
+  | {
+      type: 'plugin';
+      pluginId: string;
+    }
+  | {
+      type: 'module';
+      pluginId: string;
+      moduleId: string;
+    };
+
+export interface InstanceMetadataService {
+  getInstalledFeatures: () => BackendFeatureMeta[];
+}

packages/backend-plugin-api/src/services/definitions/coreServices.ts

@@ -251,4 +251,15 @@ export namespace coreServices {
   export const urlReader = createServiceRef<
     import('./UrlReaderService').UrlReaderService
   >({ id: 'core.urlReader' });
+
+  /**
+   * EXPERIMENTAL: Instance metadata service.
+   *
+   * @public
+   */
+  export const EXPERIMENTAL_instanceMetadata = createServiceRef<
+    import('./InstanceMetadataService').InstanceMetadataService
+  >({
+    id: 'core.instanceMetadata',
+  });
 }