Function register_connection

cassandra/cqlengine/connection.py:153–209

Add a connection to the connection registry. ``hosts`` and ``session`` are mutually exclusive, and ``consistency``, ``lazy_connect``, ``retry_connect``, and ``cluster_options`` only work with ``hosts``. Using ``hosts`` will create a new :class:`cassandra.cluster.Cluster` and :cl

(name, hosts=None, consistency=None, lazy_connect=False,
                        retry_connect=False, cluster_options=None, default=False,
                        session=None)

def register_connection(name, hosts=None, consistency=None, lazy_connect=False,
                        retry_connect=False, cluster_options=None, default=False,
                        session=None):
    """
    Add a connection to the connection registry. ``hosts`` and ``session`` are
    mutually exclusive, and ``consistency``, ``lazy_connect``,
    ``retry_connect``, and ``cluster_options`` only work with ``hosts``. Using
    ``hosts`` will create a new :class:`cassandra.cluster.Cluster` and
    :class:`cassandra.cluster.Session`.

    :param list hosts: list of hosts, (``contact_points`` for :class:`cassandra.cluster.Cluster`).
    :param int consistency: The default :class:`~.ConsistencyLevel` for the
        registered connection's new session. Default is the same as
        :attr:`.Session.default_consistency_level`. For use with ``hosts`` only;
        will fail when used with ``session``.
    :param bool lazy_connect: True if should not connect until first use. For
        use with ``hosts`` only; will fail when used with ``session``.
    :param bool retry_connect: True if we should retry to connect even if there
        was a connection failure initially. For use with ``hosts`` only; will
        fail when used with ``session``.
    :param dict cluster_options: A dict of options to be used as keyword
        arguments to :class:`cassandra.cluster.Cluster`. For use with ``hosts``
        only; will fail when used with ``session``.
    :param bool default: If True, set the new connection as the cqlengine
        default
    :param Session session: A :class:`cassandra.cluster.Session` to be used in
        the created connection.
    """

    if name in _connections:
        log.warning("Registering connection '{0}' when it already exists.".format(name))

    if session is not None:
        invalid_config_args = (hosts is not None or
                               consistency is not None or
                               lazy_connect is not False or
                               retry_connect is not False or
                               cluster_options is not None)
        if invalid_config_args:
            raise CQLEngineException(
                "Session configuration arguments and 'session' argument are mutually exclusive"
            )
        conn = Connection.from_session(name, session=session)
    else:  # use hosts argument
        conn = Connection(
            name, hosts=hosts,
            consistency=consistency, lazy_connect=lazy_connect,
            retry_connect=retry_connect, cluster_options=cluster_options
        )
        conn.setup()

    _connections[name] = conn

    if default:
        set_default_connection(name)

    return conn