You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: online_notifications_controller.rb
    path of file: ./repos/zammad/app/controllers
    
    the code of the file until where you have to start completion: # Copyright (C) 2012-2024 Zammad Foundation, https://zammad-foundation.org/

class OnlineNotificationsController < ApplicationController
  prepend_before_action -> { authorize! }, only: %i[show update destroy]
  prepend_befo
    
  def mark_all_as_read
    OnlineNotification
      .list(current_user, limit: nil, access: 'ignore')
      .where(seen: false)
      .in_batches
      .each_record do |notification|
        notification.update!(seen: true)
      end

    render json: {}, status: :ok
  end