Allow asynchronous rebase operations to be monitored

This MR introduces tracking of the `rebase_jid` for merge requests. As
with `merge_ongoing?`, `rebase_in_progress?` will now return true if a
rebase is proceeding in sidekiq.

After one release, we should remove the Gitaly-based lookup of rebases.
It is much better to track this kind of thing via the database.

1 files changed, 4 insertions, 1 deletions

diff --git a/lib/api/api.rb b/lib/api/api.rb
index 20f8c637274..42499c5b41e 100644
--- a/lib/api/api.rb
+++ b/lib/api/api.rb
@@ -52,7 +52,10 @@ module API
       rack_response({ 'message' => '404 Not found' }.to_json, 404)
     end
 
-    rescue_from ::Gitlab::ExclusiveLeaseHelpers::FailedToObtainLockError do
+    rescue_from(
+      ::ActiveRecord::StaleObjectError,
+      ::Gitlab::ExclusiveLeaseHelpers::FailedToObtainLockError
+    ) do
       rack_response({ 'message' => '409 Conflict: Resource lock' }.to_json, 409)
     end