1 files changed, 25 insertions, 0 deletions
diff --git a/lib/gitlab/background_migration/digest_column.rb b/lib/gitlab/background_migration/digest_column.rb
new file mode 100644
index 00000000000..22a3bb8f8f3
--- /dev/null
+++ b/lib/gitlab/background_migration/digest_column.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+# rubocop:disable Style/Documentation
+module Gitlab
+  module BackgroundMigration
+    class DigestColumn
+      class PersonalAccessToken < ActiveRecord::Base
+        self.table_name = 'personal_access_tokens'
+      end
+
+      def perform(model, attribute_from, attribute_to, start_id, stop_id)
+        model = model.constantize if model.is_a?(String)
+
+        model.transaction do
+          relation = model.where(id: start_id..stop_id).where.not(attribute_from => nil).lock
+
+          relation.each do |instance|
+            instance.update_columns(attribute_to => Gitlab::CryptoHelper.sha256(instance.read_attribute(attribute_from)),
+                                    attribute_from => nil)
+          end
+        end
+      end
+    end
+  end
+end