MongoDB\Driver\Session::getServer

说明

Returns the MongoDB\Driver\Server to which this session is pinned. If the session is not pinned to a server, null will be returned.

Session pinning is primarily used for sharded transactions, as all commands within a sharded transaction must be sent to the same mongos instance. This method is intended to be used by libraries built atop the extension to allow use of a pinned server instead of invoking server selection.