Class _ConnectionFairy

lib/sqlalchemy/pool/base.py:1193–1522

Proxies a DBAPI connection and provides return-on-dereference support. This is an internal object used by the :class:`_pool.Pool` implementation to provide context management to a DBAPI connection delivered by that :class:`_pool.Pool`. The public facing interface for this class

class _ConnectionFairy(PoolProxiedConnection):
    """Proxies a DBAPI connection and provides return-on-dereference
    support.

    This is an internal object used by the :class:`_pool.Pool` implementation
    to provide context management to a DBAPI connection delivered by
    that :class:`_pool.Pool`.   The public facing interface for this class
    is described by the :class:`.PoolProxiedConnection` class.  See that
    class for public API details.

    The name "fairy" is inspired by the fact that the
    :class:`._ConnectionFairy` object's lifespan is transitory, as it lasts
    only for the length of a specific DBAPI connection being checked out from
    the pool, and additionally that as a transparent proxy, it is mostly
    invisible.

    .. seealso::

        :class:`.PoolProxiedConnection`

        :class:`.ConnectionPoolEntry`


    """

    __slots__ = (
        "dbapi_connection",
        "_connection_record",
        "_echo",
        "_pool",
        "_counter",
        "__weakref__",
        "__dict__",
    )

    pool: Pool
    dbapi_connection: DBAPIConnection
    _echo: log._EchoFlagType

    def __init__(
        self,
        pool: Pool,
        dbapi_connection: DBAPIConnection,
        connection_record: _ConnectionRecord,
        echo: log._EchoFlagType,
    ):
        self._pool = pool
        self._counter = 0
        self.dbapi_connection = dbapi_connection
        self._connection_record = connection_record
        self._echo = echo

    _connection_record: Optional[_ConnectionRecord]

    @property
    def driver_connection(self) -> Optional[Any]:  # type: ignore[override]  # mypy#4125  # noqa: E501
        if self._connection_record is None:
            return None