From 9344fdf1b67e551b63412b2df9ce16f390c0c6fa Mon Sep 17 00:00:00 2001
From: Otto Sichert <git@ottosichert.de>
Date: Thu, 16 Jun 2022 00:40:26 +0200
Subject: [PATCH] Simplify guarding against corrupt ZIP files

Signed-off-by: Otto Sichert <git@ottosichert.de>
---
 .../src/reading/tree/ZipArchiveResponse.ts    | 32 +++++++------------
 1 file changed, 11 insertions(+), 21 deletions(-)

diff --git a/packages/backend-common/src/reading/tree/ZipArchiveResponse.ts b/packages/backend-common/src/reading/tree/ZipArchiveResponse.ts
index 418f32b155..501113d9f1 100644
--- a/packages/backend-common/src/reading/tree/ZipArchiveResponse.ts
+++ b/packages/backend-common/src/reading/tree/ZipArchiveResponse.ts
@@ -26,6 +26,14 @@ import {
 } from '../types';
 import { streamToTimeoutPromise } from './util';
 
+const guardCorruptZipStream = (stream: Readable) =>
+  streamToTimeoutPromise(stream, {
+    eventName: 'entry',
+    timeoutMs: 3000,
+    getError: (entry: Entry) =>
+      new Error(`Timed out while unzipping ${entry.type}: ${entry.path}`),
+  });
+
 /**
  * Wraps a zip archive stream into a tree response reader.
  */
@@ -104,13 +112,7 @@ export class ZipArchiveResponse implements ReadTreeResponse {
           entry.autodrain();
         }
       });
-
-    await streamToTimeoutPromise(parseStream, {
-      eventName: 'entry',
-      timeoutMs: 3000,
-      getError: (entry: Entry) =>
-        new Error(`Timed out while unzipping ${entry.type}: ${entry.path}`),
-    });
+    await guardCorruptZipStream(parseStream);
 
     return files;
   }
@@ -132,13 +134,7 @@ export class ZipArchiveResponse implements ReadTreeResponse {
           entry.autodrain();
         }
       });
-
-    await streamToTimeoutPromise(parseStream, {
-      eventName: 'entry',
-      timeoutMs: 3000,
-      getError: (entry: Entry) =>
-        new Error(`Timed out while unzipping ${entry.type}: ${entry.path}`),
-    });
+    await guardCorruptZipStream(parseStream);
 
     archive.finalize();
 
@@ -168,13 +164,7 @@ export class ZipArchiveResponse implements ReadTreeResponse {
           entry.autodrain();
         }
       });
-
-    await streamToTimeoutPromise(parseStream, {
-      eventName: 'entry',
-      timeoutMs: 3000,
-      getError: (entry: Entry) =>
-        new Error(`Timed out while unzipping ${entry.type}: ${entry.path}`),
-    });
+    await guardCorruptZipStream(parseStream);
 
     return dir;
   }