applyAction: [required] The pending maintenance action to apply to the resource.
Valid actions are:
ENGINE_UPDATE
ENGINE_UPGRADE
SECURITY_UPDATE
OS_UPDATE
MASTER_USER_PASSWORD_UPDATE
applyOn: A specific date to apply the pending maintenance action. Required if opt-in-type is APPLY_ON. Format: yyyy/MM/dd HH:mm-yyyy/MM/dd HH:mm
optInType: [required] A value that specifies the type of opt-in request, or undoes an opt-in request. An opt-in request of type IMMEDIATE can't be undone.
resourceArn: [required] The Amazon DocumentDB Amazon Resource Name (ARN) of the resource to which the pending maintenance action applies.