allow a list of AppConfigs to be supplied at runtime

Signed-off-by: Oleg S <97077423+RobotSail@users.noreply.github.com>

.changeset/spotty-cougars-wink.md

@@ -1,6 +0,0 @@
----
-'@backstage/backend-app-api': minor
-'@backstage/config-loader': minor
----
-
-Introduces the ability to merge configs and JsonObjects

packages/backend-app-api/api-report.md

@@ -179,7 +179,7 @@ export const lifecycleServiceFactory: () => ServiceFactory<
 export function loadBackendConfig(options: {
   remote?: LoadConfigOptionsRemote;
   argv: string[];
-  additionalConfig?: AppConfig;
+  additionalConfigs?: AppConfig[];
 }): Promise<{
   config: Config;
 }>;

packages/backend-app-api/src/config/ObservableConfigProxy.ts

@@ -16,7 +16,7 @@
 
 import { ConfigService } from '@backstage/backend-plugin-api';
 import { ConfigReader } from '@backstage/config';
-import type { JsonValue } from '@backstage/types';
+import { JsonValue } from '@backstage/types';
 
 export class ObservableConfigProxy implements ConfigService {
   private config: ConfigService = new ConfigReader({});

packages/backend-app-api/src/config/config.ts

@@ -71,7 +71,7 @@ export async function createConfigSecretEnumerator(options: {
 export async function loadBackendConfig(options: {
   remote?: LoadConfigOptionsRemote;
   argv: string[];
-  additionalConfig?: AppConfig;
+  additionalConfigs?: AppConfig[];
 }): Promise<{ config: Config }> {
   const args = parseArgs(options.argv);
 
@@ -115,11 +115,9 @@ export async function loadBackendConfig(options: {
     `Loaded config from ${appConfigs.map(c => c.context).join(', ')}`,
   );
 
-  // add the additional config if provided
-  if (options.additionalConfig) {
-    appConfigs.push(options.additionalConfig);
+  if (options.additionalConfigs) {
+    appConfigs.push(...options.additionalConfigs);
   }
-
   config.setConfig(ConfigReader.fromConfigs(appConfigs));
 
   return { config };

packages/backend-common/api-report.md

@@ -6,9 +6,8 @@
 /// <reference types="node" />
 /// <reference types="webpack-env" />
 
+import { AppConfig } from '@backstage/config';
 import { AwsCredentialsManager } from '@backstage/integration-aws-node';
-import type { AppConfig } from '@backstage/config';
-import aws from 'aws-sdk';
 import { AwsS3Integration } from '@backstage/integration';
 import { AzureIntegration } from '@backstage/integration';
 import { BackendFeature } from '@backstage/backend-plugin-api';

packages/backend-common/src/config.ts

@@ -19,7 +19,7 @@ import {
   loadBackendConfig as newLoadBackendConfig,
 } from '@backstage/backend-app-api';
 import { LoggerService } from '@backstage/backend-plugin-api';
-import type { AppConfig, Config } from '@backstage/config';
+import { AppConfig, Config } from '@backstage/config';
 import { LoadConfigOptionsRemote } from '@backstage/config-loader';
 import { setRootLoggerRedactionList } from './logging/createRootLogger';
 

packages/config-loader/src/loader.ts

@@ -139,11 +139,8 @@ export async function loadConfig(
 
   const env = envFunc ?? (async (name: string) => process.env[name]);
 
-  const loadConfigFiles = async (): Promise<{
-    fileConfigs: AppConfig[];
-    loadedPaths: Set<string>;
-  }> => {
-    const fileConfigs: AppConfig[] = [];
+  const loadConfigFiles = async () => {
+    const fileConfigs = [];
     const loadedPaths = new Set<string>();
 
     for (const configPath of configPaths) {
@@ -179,7 +176,7 @@ export async function loadConfig(
     return { fileConfigs, loadedPaths };
   };
 
-  const loadRemoteConfigFiles = async (): Promise<AppConfig[]> => {
+  const loadRemoteConfigFiles = async () => {
     const configs: AppConfig[] = [];
 
     const readConfigFromUrl = async (url: string) => {