Function set_attribute

lib/sqlalchemy/orm/attributes.py:2739–2770

Set the value of an attribute, firing history events. This function may be used regardless of instrumentation applied directly to the class, i.e. no descriptors are required. Custom attribute management schemes will need to make usage of this method to establish attribute state as u

(
    instance: object,
    key: str,
    value: Any,
    initiator: Optional[AttributeEventToken] = None,
)

def set_attribute(
    instance: object,
    key: str,
    value: Any,
    initiator: Optional[AttributeEventToken] = None,
) -> None:
    """Set the value of an attribute, firing history events.

    This function may be used regardless of instrumentation
    applied directly to the class, i.e. no descriptors are required.
    Custom attribute management schemes will need to make usage
    of this method to establish attribute state as understood
    by SQLAlchemy.

    :param instance: the object that will be modified

    :param key: string name of the attribute

    :param value: value to assign

    :param initiator: an instance of :class:`.Event` that would have
     been propagated from a previous event listener.  This argument
     is used when the :func:`.set_attribute` function is being used within
     an existing event listening function where an :class:`.Event` object
     is being supplied; the object may be used to track the origin of the
     chain of events.

     .. versionadded:: 1.2.3

    """
    state, dict_ = instance_state(instance), instance_dict(instance)
    state.manager[key].impl.set(state, dict_, value, initiator)


def get_attribute(instance: object, key: str) -> Any: