1 files changed, 53 insertions, 0 deletions
diff --git a/lib/gitlab/pages/migration_helper.rb b/lib/gitlab/pages/migration_helper.rb
new file mode 100644
index 00000000000..8f8667fafd9
--- /dev/null
+++ b/lib/gitlab/pages/migration_helper.rb
@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Pages
+    class MigrationHelper
+      def initialize(logger = nil)
+        @logger = logger
+      end
+
+      def migrate_to_remote_storage
+        deployments = ::PagesDeployment.with_files_stored_locally
+        migrate(deployments, ObjectStorage::Store::REMOTE)
+      end
+
+      def migrate_to_local_storage
+        deployments = ::PagesDeployment.with_files_stored_remotely
+        migrate(deployments, ObjectStorage::Store::LOCAL)
+      end
+
+      private
+
+      def batch_size
+        ENV.fetch('MIGRATION_BATCH_SIZE', 10).to_i
+      end
+
+      def migrate(deployments, store)
+        deployments.find_each(batch_size: batch_size) do |deployment| # rubocop:disable CodeReuse/ActiveRecord
+          deployment.file.migrate!(store)
+
+          log_success(deployment, store)
+        rescue => e
+          log_error(e, deployment)
+        end
+      end
+
+      def log_success(deployment, store)
+        logger.info("Transferred deployment ID #{deployment.id} of type #{deployment.file_type} with size #{deployment.size} to #{storage_label(store)} storage")
+      end
+
+      def log_error(err, deployment)
+        logger.warn("Failed to transfer deployment of type #{deployment.file_type} and ID #{deployment.id} with error: #{err.message}")
+      end
+
+      def storage_label(store)
+        if store == ObjectStorage::Store::LOCAL
+          'local'
+        else
+          'object'
+        end
+      end
+    end
+  end
+end