🐛 Correct race condition in chunked uploads

In multi-pod environments with a shared file system, chunked uploads were failing due to a race condition. The file size was being read from a cache, which could be stale if another pod had recently written a chunk. This resulted in an incorrect size check, causing parts of the file to be overwritten.

This commit fixes the issue by changing how the file size is retrieved. It now opens the file for reading to get the current size directly from the file handle, bypassing any filesystem attribute caching. This ensures an accurate size check and prevents file corruption during chunked uploads.

Author: ShanaLMoore

app/controllers/hyrax/uploads_controller_decorator.rb

@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+# OVERRIDE Hyrax v5.0.4 to fix a race condition in chunked uploads for multi-pod environments with a shared file system.
+# To prevent file corruption from stale cache reads, the file size is now read directly from the file handle to ensure an accurate size check.
+module Hyrax
+  module UploadsControllerDecorator
+    private
+
+    def handle_chunk(content_range, chunk)
+      file_path = @upload.file.path
+
+      current_size = 0
+      if file_path && File.exist?(file_path)
+        File.open(file_path, 'r') { |f| current_size = f.size }
+      end
+
+      begin_of_chunk = content_range[/\ (.*?)-/, 1].to_i
+
+      if @upload.file.present? && begin_of_chunk == current_size
+        File.open(file_path, 'ab') { |f| f.write(chunk.read) }
+      else
+        @upload.file = chunk
+      end
+    end
+  end
+end
+
+Hyrax::UploadsController.prepend(Hyrax::UploadsControllerDecorator)