chore(server): customize config merge logic (#11400)

packages/backend/server/src/core/config/__tests__/service.spec.ts

@@ -23,7 +23,7 @@ test.after.always(async () => {
 });
 
 test('should update config', async t => {
-  const oldValue = service.config.server.externalUrl;
+  const oldValue = service.getConfig().server.externalUrl;
   const newValue = faker.internet.url();
   await service.updateConfig(user.id, [
     {
@@ -33,8 +33,8 @@ test('should update config', async t => {
     },
   ]);
 
-  t.not(service.config.server.externalUrl, oldValue);
-  t.is(service.config.server.externalUrl, newValue);
+  t.not(service.getConfig().server.externalUrl, oldValue);
+  t.is(service.getConfig().server.externalUrl, newValue);
 });
 
 test('should validate config before update', async t => {
@@ -53,7 +53,7 @@ Error: Invalid url`,
     }
   );
 
-  t.not(service.config.server.externalUrl, 'invalid-url');
+  t.not(service.getConfig().server.externalUrl, 'invalid-url');
 
   await t.throwsAsync(
     service.updateConfig(user.id, [
@@ -68,8 +68,11 @@ Error: Invalid url`,
     }
   );
 
-  // @ts-expect-error allow
-  t.is(service.config.auth['unknown-key'], undefined);
+  t.is(
+    // @ts-expect-error testing
+    service.getConfig().auth['unknown-key'],
+    undefined
+  );
 });
 
 test('should emit config.init event', async t => {
@@ -77,12 +80,12 @@ test('should emit config.init event', async t => {
   const event = module.event.last('config.init');
   t.is(event.name, 'config.init');
   t.deepEqual(event.payload, {
-    config: service.config,
+    config: service.getConfig(),
   });
 });
 
 test('should revalidate config', async t => {
-  const outdatedValue = service.config.server.externalUrl;
+  const outdatedValue = service.getConfig().server.externalUrl;
   const newValue = faker.internet.url();
 
   await models.appConfig.save(user.id, [
@@ -94,8 +97,8 @@ test('should revalidate config', async t => {
 
   await service.revalidateConfig();
 
-  t.not(service.config.server.externalUrl, outdatedValue);
-  t.is(service.config.server.externalUrl, newValue);
+  t.not(service.getConfig().server.externalUrl, outdatedValue);
+  t.is(service.getConfig().server.externalUrl, newValue);
 });
 
 test('should emit config changed event', async t => {

packages/backend/server/src/core/config/resolver.ts

@@ -191,7 +191,7 @@ export class AppConfigResolver {
     description: 'get the whole app configuration',
   })
   appConfig() {
-    return this.service.config;
+    return this.service.getConfig();
   }
 
   @Mutation(() => GraphQLJSONObject, {

packages/backend/server/src/core/config/service.ts

@@ -56,8 +56,8 @@ export class ServerService implements OnApplicationBootstrap {
     this.#features.delete(feature);
   }
 
-  get config() {
-    return this.configFactory.config;
+  getConfig() {
+    return this.configFactory.clone();
   }
 
   async updateConfig(