Import use_file method from EE and use it for calculation of checksum

app/uploaders/gitlab_uploader.rb

@@ -71,6 +71,14 @@ class GitlabUploader < CarrierWave::Uploader::Base
     !!model
   end
 
+  ##
+  # ObjectStorage::Concern extends this method for remote files
+  def use_file
+    if file_storage?
+      return yield path
+    end
+  end
+
   private
 
   # Designed to be overridden by child uploaders that have a dynamic path

app/uploaders/job_artifact_uploader.rb

@@ -28,7 +28,9 @@ class JobArtifactUploader < GitlabUploader
   private
 
   def calc_checksum
-    Digest::SHA256.file(file.path).hexdigest
+    use_file do |file_path|
+      return Digest::SHA256.file(file_path).hexdigest
+    end
   end
 
   def dynamic_segment