feat(server): use nestjs events to validate config (#7986)

* use events for config validation

* chore: better types

* add unit tests

---------

Co-authored-by: Jason Rasmussen <jrasm91@gmail.com>

server/src/domain/storage-template/storage-template.service.spec.ts

@@ -12,7 +12,7 @@ import {
   StorageTemplateService,
   defaults,
 } from '@app/domain';
-import { AssetPathType, SystemConfigKey } from '@app/infra/entities';
+import { AssetPathType, SystemConfig, SystemConfigKey } from '@app/infra/entities';
 import {
   assetStub,
   newAlbumRepositoryMock,
@@ -74,6 +74,35 @@ describe(StorageTemplateService.name, () => {
     SystemConfigCore.create(configMock).config$.next(defaults);
   });
 
+  describe('validate', () => {
+    it('should allow valid templates', () => {
+      expect(() =>
+        sut.validate({
+          newConfig: {
+            storageTemplate: {
+              template:
+                '{{y}}{{M}}{{W}}{{d}}{{h}}{{m}}{{s}}{{filename}}{{ext}}{{filetype}}{{filetypefull}}{{assetId}}{{album}}',
+            },
+          } as SystemConfig,
+          oldConfig: {} as SystemConfig,
+        }),
+      ).not.toThrow();
+    });
+
+    it('should fail for an invalid template', () => {
+      expect(() =>
+        sut.validate({
+          newConfig: {
+            storageTemplate: {
+              template: '{{foo}}',
+            },
+          } as SystemConfig,
+          oldConfig: {} as SystemConfig,
+        }),
+      ).toThrow(/Invalid storage template.*/);
+    });
+  });
+
   describe('handleMigrationSingle', () => {
     it('should skip when storage template is disabled', async () => {
       configMock.load.mockResolvedValue([{ key: SystemConfigKey.STORAGE_TEMPLATE_ENABLED, value: false }]);