fix(backend): RoleService.getAdministratorIds でユーザーIDが重複する問題を修正 (#17334)

* fix(backend): adminロールが複数付いてても通知が重複しないように

* add tests

* Update Changelog

* ✌️

Co-Authored-by: lqvp <183242690+lqvp@users.noreply.github.com>

---------

Co-authored-by: lqvp <183242690+lqvp@users.noreply.github.com>

packages/backend/src/core/RoleService.ts

@@ -533,7 +533,8 @@ export class RoleService implements OnApplicationShutdown, OnModuleInit {
 			roleId: In(administratorRoles.map(r => r.id)),
 		}) : [];
 		// TODO: isRootなアカウントも含める
-		return assigns.map(a => a.userId);
+		// Setを経由して重複を除去（ユーザIDは重複する可能性があるので）
+		return [...new Set(assigns.map(a => a.userId))].sort((x, y) => x.localeCompare(y));
 	}
 
 	@bindThis

packages/backend/src/core/SignupService.ts

@@ -164,4 +164,3 @@ export class SignupService {
 		return { account, secret };
 	}
 }
-

packages/backend/test/unit/RoleService.ts

@@ -696,6 +696,19 @@ describe('RoleService', () => {
 			expect(adminIds).toHaveLength(0);
 		});
 
+		test('should not include duplicate user IDs if a user has multiple administrator roles', async () => {
+			const adminUser = await createUser();
+			const adminRole1 = await createRole({ name: 'admin1', isAdministrator: true });
+			const adminRole2 = await createRole({ name: 'admin2', isAdministrator: true });
+
+			await roleService.assign(adminUser.id, adminRole1.id);
+			await roleService.assign(adminUser.id, adminRole2.id);
+
+			const adminIds = await roleService.getAdministratorIds();
+
+			expect(adminIds).toEqual([adminUser.id]);
+		});
+
 		// TODO: rootユーザーは現在実装に含まれていないため、テストもそれに倣う
 		test('should not include the root user', async () => {
 			const rootUser = await createUser();