Add the ability to perform background migrations

Background migrations can be used to perform long running data
migrations without these blocking a deployment procedure.

See MR https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/11854 for
more information.

1 files changed, 23 insertions, 0 deletions

diff --git a/app/workers/background_migration_worker.rb b/app/workers/background_migration_worker.rb
new file mode 100644
index 00000000000..e85e221d353
--- /dev/null
+++ b/app/workers/background_migration_worker.rb
@@ -0,0 +1,23 @@
+class BackgroundMigrationWorker
+  include Sidekiq::Worker
+  include DedicatedSidekiqQueue
+
+  # Schedules a number of jobs in bulk
+  #
+  # The `jobs` argument should be an Array of Arrays, each sub-array must be in
+  # the form:
+  #
+  #     [migration-class, [arg1, arg2, ...]]
+  def self.perform_bulk(*jobs)
+    Sidekiq::Client.push_bulk('class' => self,
+                              'queue' => sidekiq_options['queue'],
+                              'args' => jobs)
+  end
+
+  # Performs the background migration.
+  #
+  # See Gitlab::BackgroundMigration.perform for more information.
+  def perform(class_name, arguments = [])
+    Gitlab::BackgroundMigration.perform(class_name, arguments)
+  end
+end