update config handling to support internal/external split and adjust types

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

packages/backend-defaults/report-alpha.api.md

@@ -38,7 +38,7 @@ export class DefaultSystemMetadataService implements SystemMetadataService {
 // @alpha
 export const systemMetadataServiceFactory: ServiceFactory<
   SystemMetadataService,
-  'plugin',
+  'root',
   'singleton'
 >;
 

packages/backend-defaults/src/entrypoints/systemMetadata/lib/DefaultSystemMetadataService.ts

@@ -22,14 +22,49 @@ import {
   BackstageInstance,
   SystemMetadataService,
 } from '@backstage/backend-plugin-api/alpha';
+import z from 'zod';
+
+const targetObjectSchema = z.object({
+  internal: z.string(),
+  external: z.string(),
+});
 
 /**
  * @alpha
  */
 export class DefaultSystemMetadataService implements SystemMetadataService {
+  private instances: BackstageInstance[];
   constructor(
     private options: { logger: LoggerService; config: RootConfigService },
-  ) {}
+  ) {
+    const getInstances = () => {
+      const endpoints =
+        options.config.getOptionalConfigArray('discovery.instances') ?? [];
+      const instances: BackstageInstance[] = [];
+      for (const endpoint of endpoints) {
+        const baseUrl = endpoint.getOptional('baseUrl');
+        if (baseUrl) {
+          if (typeof baseUrl === 'string') {
+            instances.push({ internalUrl: baseUrl, externalUrl: baseUrl });
+          } else {
+            const parseAttempt = targetObjectSchema.safeParse(baseUrl);
+            if (parseAttempt.success) {
+              const { internal, external } = parseAttempt.data;
+              instances.push({
+                internalUrl: internal,
+                externalUrl: external,
+              });
+            }
+          }
+        }
+      }
+      return instances;
+    };
+    this.instances = getInstances();
+    this.options.config.subscribe?.(() => {
+      this.instances = getInstances();
+    });
+  }
 
   public static create(pluginEnv: {
     logger: LoggerService;
@@ -39,15 +74,6 @@ export class DefaultSystemMetadataService implements SystemMetadataService {
   }
 
   async listInstances() {
-    const endpoints =
-      this.options.config.getOptionalConfigArray('discovery.instances') ?? [];
-    const instances: BackstageInstance[] = [];
-    for (const endpoint of endpoints) {
-      const baseUrl = endpoint.getOptionalString('baseUrl');
-      if (baseUrl) {
-        instances.push({ url: baseUrl });
-      }
-    }
-    return instances;
+    return this.instances;
   }
 }

packages/backend-defaults/src/entrypoints/systemMetadata/lib/createSystemMetadataRouter.ts

@@ -43,17 +43,20 @@ export async function createSystemMetadataRouter(options: {
     const featurePromises = await Promise.allSettled(
       instances.map(async instance => {
         const response = await fetch(
-          `${instance.url}/.backstage/instanceMetadata/v1/features/installed`,
+          `${instance.internalUrl}/.backstage/instanceMetadata/v1/features/installed`,
         );
         if (response.ok) {
           return { instance, response: await response.json() };
         }
         throw new Error(
-          `Failed to fetch installed features from ${instance.url}`,
+          `Failed to fetch installed features from ${instance.internalUrl}`,
         );
       }),
     );
-    const pluginByInstance: Record<string, string[]> = {};
+    const pluginByInstance: Record<
+      string,
+      { internalUrl: string; externalUrl: string }[]
+    > = {};
     for (const result of featurePromises) {
       if (result.status !== 'fulfilled') {
         logger.error(`Failed to fetch installed features: ${result.reason}`);
@@ -67,7 +70,7 @@ export async function createSystemMetadataRouter(options: {
           if (!pluginByInstance[feature.pluginId]) {
             pluginByInstance[feature.pluginId] = [];
           }
-          pluginByInstance[feature.pluginId].push(instance.url);
+          pluginByInstance[feature.pluginId].push(instance);
         }
       }
     }

packages/backend-plugin-api/src/alpha/index.ts

@@ -40,5 +40,4 @@ export const systemMetadataServiceRef = createServiceRef<
 export type {
   BackstageInstance,
   SystemMetadataService,
-  Target,
 } from './services/definitions/SystemMetadataService';

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

@@ -14,14 +14,12 @@
  * limitations under the License.
  */
 
-/** @alpha */
-export type Target = string | { internal: string; external: string };
-
 /**
  * @alpha
  */
 export interface BackstageInstance {
-  url: Target;
+  internalUrl: string;
+  externalUrl: string;
 }
 
 /**

packages/backend/app-config.split.yaml

@@ -6,4 +6,6 @@ discovery:
       plugins: [catalog]
   instances:
     - baseUrl: http://localhost:7007
-    - baseUrl: http://localhost:7008
+    - baseUrl:
+        internal: http://localhost:7008
+        external: http://127.0.0.1:7008