Merge branch 'fix/gb/process-scheduled-background-migrations' into 'master'

Process scheduled background migrations as well

Closes #34951

See merge request !12787

1 files changed, 28 insertions, 7 deletions

diff --git a/lib/gitlab/background_migration.rb b/lib/gitlab/background_migration.rb
index d95ecd7b291..b0741b1fba7 100644
--- a/lib/gitlab/background_migration.rb
+++ b/lib/gitlab/background_migration.rb
@@ -1,24 +1,45 @@
 module Gitlab
   module BackgroundMigration
+    def self.queue
+      @queue ||= BackgroundMigrationWorker.sidekiq_options['queue']
+    end
+
     # Begins stealing jobs from the background migrations queue, blocking the
     # caller until all jobs have been completed.
     #
+    # When a migration raises a StandardError is is going to be retries up to
+    # three times, for example, to recover from a deadlock.
+    #
+    # When Exception is being raised, it enqueues the migration again, and
+    # re-raises the exception.
+    #
     # steal_class - The name of the class for which to steal jobs.
     def self.steal(steal_class)
-      queue = Sidekiq::Queue
-        .new(BackgroundMigrationWorker.sidekiq_options['queue'])
+      enqueued = Sidekiq::Queue.new(self.queue)
+      scheduled = Sidekiq::ScheduledSet.new
 
-      queue.each do |job|
-        migration_class, migration_args = job.args
+      [scheduled, enqueued].each do |queue|
+        queue.each do |job|
+          migration_class, migration_args = job.args
 
-        next unless migration_class == steal_class
+          next unless job.queue == self.queue
+          next unless migration_class == steal_class
 
-        perform(migration_class, migration_args)
+          begin
+            perform(migration_class, migration_args, retries: 3) if job.delete
+          rescue Exception # rubocop:disable Lint/RescueException
+            BackgroundMigrationWorker # enqueue this migration again
+              .perform_async(migration_class, migration_args)
 
-        job.delete
+            raise
+          end
+        end
       end
     end
 
+    ##
+    # Performs a background migration.
+    #
     # class_name - The name of the background migration class as defined in the
     #              Gitlab::BackgroundMigration namespace.
     #