# File lib/fog/compute/openstack/requests/list_security_groups.rb, line 32
        def list_security_groups(options = {})
          server_id = if options.kind_of?(Hash)
                        options.delete(:server_id)
                      else
                        options
                      end

          security_groups = data[:security_groups].values

          groups = if server_id
                     server_group_names =
                       Array(data[:server_security_group_map][server_id])

                     server_group_names.map do |name|
                       security_groups.find do |sg|
                         sg['name'] == name
                       end
                     end.compact
                   else
                     security_groups
                   end

          Excon::Response.new(
            :body    => {'security_groups' => groups},
            :headers => {
              "X-Compute-Request-Id" => "req-#{Fog::Mock.random_base64(36)}",
              "Content-Type"         => "application/json",
              "Date"                 => Date.new
            },
            :status  => 200
          )
        end