More lenient attachment v2 migration

ts/util/encryptLegacyAttachment.ts

@@ -2,10 +2,12 @@
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import LRU from 'lru-cache';
+
 import type {
   AddressableAttachmentType,
   LocalAttachmentV2Type,
 } from '../types/Attachment';
+import * as log from '../logging/log';
 import { AttachmentDisposition } from './getLocalAttachmentUrl';
 
 let setCheck = false;
@@ -15,6 +17,7 @@ const lru = new LRU<string, Promise<LocalAttachmentV2Type>>({
 });
 
 export type EncryptLegacyAttachmentOptionsType = Readonly<{
+  logId: string;
   disposition?: AttachmentDisposition;
   readAttachmentData: (
     attachment: Partial<AddressableAttachmentType>
@@ -43,12 +46,18 @@ export async function encryptLegacyAttachment<
     promise = doEncrypt(attachment, options);
     lru.set(cacheKey, promise);
   }
-  const modern = await promise;
+  try {
+    const modern = await promise;
 
-  return {
-    ...attachment,
-    ...modern,
-  };
+    return {
+      ...attachment,
+      ...modern,
+    };
+  } catch (error) {
+    const { logId } = options;
+    log.error(`${logId}: migration failed, falling back to original`, error);
+    return attachment;
+  }
 }
 
 async function doEncrypt<T extends Partial<AddressableAttachmentType>>(