From f94918bebd83eba9cb8c9d631ac60df500f253f8 Mon Sep 17 00:00:00 2001
From: Robert <robertslootjes@gmail.com>
Date: Fri, 19 Apr 2019 13:10:49 +0200
Subject: [PATCH] Prevent possible download counter race condition

---
 server/routes/download.js | 2 +-
 server/storage/index.js   | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/server/routes/download.js b/server/routes/download.js
index 7828c880..006f11c2 100644
--- a/server/routes/download.js
+++ b/server/routes/download.js
@@ -34,7 +34,7 @@ module.exports = async function(req, res) {
         if (dl >= dlimit) {
           await storage.del(id);
         } else {
-          await storage.setField(id, 'dl', dl);
+          await storage.incrementField(id, 'dl');
         }
       } catch (e) {
         log.info('StorageError:', id);
diff --git a/server/storage/index.js b/server/storage/index.js
index 1c80f26c..3e46c5c1 100644
--- a/server/storage/index.js
+++ b/server/storage/index.js
@@ -62,6 +62,10 @@ class DB {
     this.redis.hset(id, key, value);
   }
 
+  incrementField(id, key, increment = 1) {
+    this.redis.hincrby(id, key, increment);
+  }
+
   async del(id) {
     const filePath = await this.getPrefixedId(id);
     this.storage.del(filePath);