1 files changed, 45 insertions, 0 deletions
diff --git a/lib/gitlab/background_migration/migrate_personal_namespace_project_maintainer_to_owner.rb b/lib/gitlab/background_migration/migrate_personal_namespace_project_maintainer_to_owner.rb
new file mode 100644
index 00000000000..49eff6e2771
--- /dev/null
+++ b/lib/gitlab/background_migration/migrate_personal_namespace_project_maintainer_to_owner.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module BackgroundMigration
+    # Migrates personal namespace project `maintainer` memberships (for the associated user only) to OWNER
+    # Does not create any missing records, simply migrates existing ones
+    class MigratePersonalNamespaceProjectMaintainerToOwner
+      include Gitlab::Database::DynamicModelHelpers
+
+      def perform(start_id, end_id, batch_table, batch_column, sub_batch_size, pause_ms)
+        parent_batch_relation = relation_scoped_to_range(batch_table, batch_column, start_id, end_id)
+
+        parent_batch_relation.each_batch(column: batch_column, of: sub_batch_size) do |sub_batch|
+          batch_metrics.time_operation(:update_all) do
+            sub_batch.update_all('access_level = 50')
+          end
+
+          pause_ms = 0 if pause_ms < 0
+          sleep(pause_ms * 0.001)
+        end
+      end
+
+      def batch_metrics
+        @batch_metrics ||= Gitlab::Database::BackgroundMigration::BatchMetrics.new
+      end
+
+      private
+
+      def relation_scoped_to_range(source_table, source_key_column, start_id, stop_id)
+        # members of projects within their own personal namespace
+
+        # rubocop: disable CodeReuse/ActiveRecord
+        define_batchable_model(:members, connection: ApplicationRecord.connection)
+          .where(source_key_column => start_id..stop_id)
+          .joins("INNER JOIN projects ON members.source_id = projects.id")
+          .joins("INNER JOIN namespaces ON projects.namespace_id = namespaces.id")
+          .where(type: 'ProjectMember')
+          .where("namespaces.type = 'User'")
+          .where('members.access_level < 50')
+          .where('namespaces.owner_id = members.user_id')
+      end
+    end
+    # rubocop: enable CodeReuse/ActiveRecord
+  end
+end