(mongodb >=1.13.0)
MongoDB\Driver\Monitoring\SDAMSubscriber::topologyChanged — Notification method for a topology description change
$event): voidIf the subscriber is registered, this method is called when the topology's description changes. For example, a topology discovering a new replica set primary would cause its topology description to change.
event (MongoDB\Driver\Monitoring\TopologyChangedEvent)An event object encapsulating information about the changed topology description.
No value is returned.