From 61610a61fa1508015d1d81867a45ba2a59c624ec Mon Sep 17 00:00:00 2001
From: Sam <sam.saffron@gmail.com>
Date: Tue, 2 Jul 2024 19:06:46 +1000
Subject: [PATCH] FIX: disallow concurrent downloads of hotlinked images
 (#27676)

---
 app/jobs/regular/pull_hotlinked_images.rb | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/app/jobs/regular/pull_hotlinked_images.rb b/app/jobs/regular/pull_hotlinked_images.rb
index 19e216f22e6..8baf5d35e30 100644
--- a/app/jobs/regular/pull_hotlinked_images.rb
+++ b/app/jobs/regular/pull_hotlinked_images.rb
@@ -14,6 +14,17 @@ module Jobs
       @post_id = args[:post_id]
       raise Discourse::InvalidParameters.new(:post_id) if @post_id.blank?
 
+      # in test we have no choice cause we don't want to cause a deadlock
+      if Jobs.run_immediately?
+        pull_hotlinked_images
+      else
+        DistributedMutex.synchronize("pull_hotlinked_images_#{@post_id}", validity: 2.minutes) do
+          pull_hotlinked_images
+        end
+      end
+    end
+
+    def pull_hotlinked_images
       post = Post.find_by(id: @post_id)
       return if post.nil? || post.topic.nil?