logging current user.id in Rails logs

application.rb

    config.log_tags = [
      :request_id,
      :subdomain,
      ->(req) {
        session_key = (Rails.application.config.session_options || {})[:key]
        session_data = req.cookie_jar.encrypted[session_key] || {}
        user_id = session_data["user_id"] || "guest"
        "user: #{user_id.to_s}"
      }
    ]