messageType

The type of notification that triggers CC to run an evaluation for a rule. You can specify the following notification types:

• `ConfigurationItemChangeNotification` - Triggers an evaluation when CC delivers a configuration item as a result of a resource change.

• `OversizedConfigurationItemChangeNotification` - Triggers an evaluation when CC delivers an oversized configuration item. CC may generate this notification type when a resource changes and the notification exceeds the maximum size allowed by Amazon SNS.

• `ScheduledNotification` - Triggers a periodic evaluation at the frequency specified for `MaximumExecutionFrequency`.

• `ConfigurationSnapshotDeliveryCompleted` - Triggers a periodic evaluation when CC delivers a configuration snapshot. If you want your custom rule to be triggered by configuration changes, specify two SourceDetail objects, one for `ConfigurationItemChangeNotification` and one for `OversizedConfigurationItemChangeNotification`.