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packages/app/src/server/routes/apiv3/g2g-transfer.ts

@@ -261,6 +261,7 @@ module.exports = (crowi: Crowi): Router => {
   });
 
   // TODO: verify transfer key
+  // This endpoint uses multer's MemoryStorage since the received data should be persisted directly on attachment storage.
   receiveRouter.post('/attachment', uploadsForAttachment.single('content'), /* verifyAndExtractTransferKey, */
     async(req: Request & { transferKey: TransferKey }, res: ApiV3Response) => {
       const { file } = req;
@@ -275,6 +276,8 @@ module.exports = (crowi: Crowi): Router => {
         return res.apiv3Err(new ErrorV3('Failed to parse body.', 'parse_failed'), 500);
       }
 
+      // convert Buffer to stream
+      // see: https://stackoverflow.com/a/62143160
       await g2gTransferReceiverService.receiveAttachment(Readable.from(file.buffer), attachmentMap);
 
       return res.apiv3({ message: 'Successfully imported attached file.' });