docs: def parse_connection_string(self, connection):
          """Parse string as returned by the ``connected_users_info`` or ``user_sessions_info`` API calls.
  
          >>> EjabberdBackendBase().parse_connection_string('c2s_tls')
          (0, True, False)
          >>> EjabberdBackendBase().parse_connection_string('c2s_compressed_tls')
          (0, True, True)
          >>> EjabberdBackendBase().parse_connection_string('http_bind')
          (2, None, None)
  
          :param connection: The connection string as returned by the ejabberd APIs.
          :type  connection: str
          :return: A tuple representing the conntion type, if it is encrypted and if it uses XMPP stream
              compression.
          :rtype: tuple
          """
          # TODO: Websockets, HTTP Polling
          if connection == 'c2s_tls':
              return CONNECTION_XMPP, True, False
          elif connection == 'c2s_compressed_tls':
              return CONNECTION_XMPP, True, True
          elif connection == 'http_bind':
              return CONNECTION_HTTP_BINDING, None, None
          elif connection == 'c2s':
              return CONNECTION_XMPP, False, False
          log.warn('Could not parse connection string "%s"', connection)
          return CONNECTION_UNKNOWN, True, True