extract_expires_in (OpenID::Consumer::AssociationManager)

    # File lib/openid/consumer/associationmanager.rb, line 268
          def self.extract_expires_in(message)
            # expires_in should be a base-10 string.
            expires_in_str = message.get_arg(OPENID_NS, 'expires_in', NO_DEFAULT)
            if !(/\A\d+\Z/ =~ expires_in_str)
              raise ProtocolError, "Invalid expires_in field: #{expires_in_str}"
            end
            expires_in_str.to_i
          end