From ad63f55a0f3d5cf3ad166847fc70edf1a8b8a211 Mon Sep 17 00:00:00 2001
From: Hazelnoot <acomputerdog@gmail.com>
Date: Thu, 19 Dec 2024 11:22:26 -0500
Subject: [PATCH 1/2] add file extension to locally-stored media

---
 packages/backend/src/core/DriveService.ts | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/packages/backend/src/core/DriveService.ts b/packages/backend/src/core/DriveService.ts
index 086f2f94d5..99e0ea98dd 100644
--- a/packages/backend/src/core/DriveService.ts
+++ b/packages/backend/src/core/DriveService.ts
@@ -37,6 +37,7 @@ import { InternalStorageService } from '@/core/InternalStorageService.js';
 import { DriveFileEntityService } from '@/core/entities/DriveFileEntityService.js';
 import { UserEntityService } from '@/core/entities/UserEntityService.js';
 import { FileInfoService } from '@/core/FileInfoService.js';
+import type { FileInfo } from '@/core/FileInfoService.js';
 import { bindThis } from '@/decorators.js';
 import { RoleService } from '@/core/RoleService.js';
 import { correctFilename } from '@/misc/correct-filename.js';
@@ -139,15 +140,19 @@ export class DriveService {
 
 	/***
 	 * Save file
+	 * @param file
 	 * @param path Path for original
 	 * @param name Name for original (should be extention corrected)
-	 * @param type Content-Type for original
-	 * @param hash Hash for original
-	 * @param size Size for original
+	 * @param info File metadata
 	 */
 	@bindThis
-	private async save(file: MiDriveFile, path: string, name: string, type: string, hash: string, size: number): Promise<MiDriveFile> {
-	// thunbnail, webpublic を必要なら生成
+	private async save(file: MiDriveFile, path: string, name: string, info: FileInfo): Promise<MiDriveFile> {
+		const type = info.type.mime;
+		const ext = info.type.ext;
+		const hash = info.md5;
+		const size = info.size;
+
+		// thunbnail, webpublic を必要なら生成
 		const alts = await this.generateAlts(path, type, !file.uri);
 
 		if (this.meta.useObjectStorage) {
@@ -223,9 +228,9 @@ export class DriveService {
 
 			return await this.driveFilesRepository.insertOne(file);
 		} else { // use internal storage
-			const accessKey = randomUUID();
-			const thumbnailAccessKey = 'thumbnail-' + randomUUID();
-			const webpublicAccessKey = 'webpublic-' + randomUUID();
+			const accessKey = `${randomUUID()}.${ext}`;
+			const thumbnailAccessKey = `thumbnail-${randomUUID()}.${ext}`;
+			const webpublicAccessKey = `webpublic-${randomUUID()}.${ext}`;
 
 			// Ugly type is just to help TS figure out that 2nd / 3rd promises are optional.
 			const promises: [Promise<string>, ...(Promise<string> | undefined)[]] = [
@@ -616,7 +621,7 @@ export class DriveService {
 				}
 			}
 		} else {
-			file = await (this.save(file, path, detectedName, info.type.mime, info.md5, info.size));
+			file = await (this.save(file, path, detectedName, info));
 		}
 
 		this.registerLogger.succ(`drive file has been created ${file.id}`);

From 0de93c2bde78bd4c4c7aed87d42cd7054955b4b2 Mon Sep 17 00:00:00 2001
From: Hazelnoot <acomputerdog@gmail.com>
Date: Thu, 19 Dec 2024 12:33:11 -0500
Subject: [PATCH 2/2] only attach file extension for browser-safe file types

---
 packages/backend/src/core/DriveService.ts | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/packages/backend/src/core/DriveService.ts b/packages/backend/src/core/DriveService.ts
index 99e0ea98dd..734ce6b88f 100644
--- a/packages/backend/src/core/DriveService.ts
+++ b/packages/backend/src/core/DriveService.ts
@@ -148,7 +148,6 @@ export class DriveService {
 	@bindThis
 	private async save(file: MiDriveFile, path: string, name: string, info: FileInfo): Promise<MiDriveFile> {
 		const type = info.type.mime;
-		const ext = info.type.ext;
 		const hash = info.md5;
 		const size = info.size;
 
@@ -228,9 +227,11 @@ export class DriveService {
 
 			return await this.driveFilesRepository.insertOne(file);
 		} else { // use internal storage
-			const accessKey = `${randomUUID()}.${ext}`;
-			const thumbnailAccessKey = `thumbnail-${randomUUID()}.${ext}`;
-			const webpublicAccessKey = `webpublic-${randomUUID()}.${ext}`;
+			const ext = FILE_TYPE_BROWSERSAFE.includes(type) ? info.type.ext : null;
+
+			const accessKey = makeFileKey(ext);
+			const thumbnailAccessKey = makeFileKey(ext, 'thumbnail');
+			const webpublicAccessKey = makeFileKey(ext, 'webpublic');
 
 			// Ugly type is just to help TS figure out that 2nd / 3rd promises are optional.
 			const promises: [Promise<string>, ...(Promise<string> | undefined)[]] = [
@@ -867,3 +868,16 @@ export class DriveService {
 		}
 	}
 }
+
+function makeFileKey(ext: string | null, prefix?: string): string {
+	const parts: string[] = [randomUUID()];
+
+	if (prefix) {
+		parts.unshift(prefix, '-');
+	}
+	if (ext) {
+		parts.push('.', ext);
+	}
+
+	return parts.join('');
+}