fix(server): sync files to disk

Ensure that all files are flushed after they've been written.

At current, files are not explicitly flushed to disk, which can cause
data corruption. In extreme circumstances, it's possible that uploaded
files may not ever be persisted at all.

server/src/middleware/file-upload.interceptor.ts

@@ -10,6 +10,7 @@ import { UploadFieldName } from 'src/dtos/asset-media.dto';
 import { RouteKey } from 'src/enum';
 import { AuthRequest } from 'src/middleware/auth.guard';
 import { LoggingRepository } from 'src/repositories/logging.repository';
+import { StorageRepository } from 'src/repositories/storage.repository';
 import { AssetMediaService } from 'src/services/asset-media.service';
 import { ImmichFile, UploadFile, UploadFiles } from 'src/types';
 import { asUploadRequest, mapToUploadFile } from 'src/utils/asset.util';
@@ -54,6 +55,7 @@ export class FileUploadInterceptor implements NestInterceptor {
   constructor(
     private reflect: Reflector,
     private assetService: AssetMediaService,
+    private storageRepository: StorageRepository,
     private logger: LoggingRepository,
   ) {
     this.logger.setContext(FileUploadInterceptor.name);
@@ -125,7 +127,18 @@ export class FileUploadInterceptor implements NestInterceptor {
     });
 
     if (!this.isAssetUploadFile(file)) {
-      this.defaultStorage._handleFile(request, file, callback);
+      this.defaultStorage._handleFile(request, file, (error, info) => {
+        if (error) {
+          return callback(error);
+        }
+        // Multer does not sync files to disk after writing.
+        //
+        // TODO: use `flush: true` in multer when available: https://github.com/expressjs/multer/issues/1381
+        this.storageRepository
+          .datasync(info!.path!)
+          .then(() => callback(null, info!))
+          .catch((error) => callback(error));
+      });
       return;
     }
 
@@ -136,7 +149,13 @@ export class FileUploadInterceptor implements NestInterceptor {
         hash.destroy();
         callback(error);
       } else {
-        callback(null, { ...info, checksum: hash.digest() });
+        this.storageRepository
+          .datasync(info!.path!)
+          .then(() => callback(null, { ...info, checksum: hash.digest() }))
+          .catch((error) => {
+            hash.destroy();
+            callback(error);
+          });
       }
     });
   }

server/src/repositories/storage.repository.ts

@@ -54,6 +54,15 @@ export class StorageRepository {
     return fs.copyFile(source, target);
   }
 
+  async datasync(filepath: string) {
+    const handle = await fs.open(filepath, 'r');
+    try {
+      await handle.datasync();
+    } finally {
+      await handle.close();
+    }
+  }
+
   stat(filepath: string) {
     return fs.stat(filepath);
   }

server/test/repositories/storage.repository.mock.ts

@@ -72,6 +72,7 @@ export const newStorageRepositoryMock = (): Mocked<RepositoryInterface<StorageRe
     walk: vitest.fn().mockImplementation(async function* () {}),
     rename: vitest.fn(),
     copyFile: vitest.fn(),
+    datasync: vitest.fn(),
     utimes: vitest.fn(),
     watch: vitest.fn().mockImplementation(makeMockWatcher({})),
   };