This is the new *Amazon CloudFormation Template Reference Guide*. Please update your bookmarks and links. For help getting started with CloudFormation, see the [Amazon CloudFormation User Guide](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/Welcome.html).

# AWS::DLM::LifecyclePolicy EventParameters
<a name="aws-properties-dlm-lifecyclepolicy-eventparameters"></a>

**[Event-based policies only]** Specifies an event that activates an event-based policy.

## Syntax
<a name="aws-properties-dlm-lifecyclepolicy-eventparameters-syntax"></a>

To declare this entity in your Amazon CloudFormation template, use the following syntax:

### JSON
<a name="aws-properties-dlm-lifecyclepolicy-eventparameters-syntax.json"></a>

```
{
  "[DescriptionRegex](#cfn-dlm-lifecyclepolicy-eventparameters-descriptionregex)" : String,
  "[EventType](#cfn-dlm-lifecyclepolicy-eventparameters-eventtype)" : String,
  "[SnapshotOwner](#cfn-dlm-lifecyclepolicy-eventparameters-snapshotowner)" : [ String, ... ]
}
```

### YAML
<a name="aws-properties-dlm-lifecyclepolicy-eventparameters-syntax.yaml"></a>

```
  [DescriptionRegex](#cfn-dlm-lifecyclepolicy-eventparameters-descriptionregex): String
  [EventType](#cfn-dlm-lifecyclepolicy-eventparameters-eventtype): String
  [SnapshotOwner](#cfn-dlm-lifecyclepolicy-eventparameters-snapshotowner): 
    - String
```

## Properties
<a name="aws-properties-dlm-lifecyclepolicy-eventparameters-properties"></a>

`DescriptionRegex`  <a name="cfn-dlm-lifecyclepolicy-eventparameters-descriptionregex"></a>
The snapshot description that can trigger the policy. The description pattern is specified using a regular expression. The policy runs only if a snapshot with a description that matches the specified pattern is shared with your account.  
For example, specifying `^.*Created for policy: policy-1234567890abcdef0.*$` configures the policy to run only if snapshots created by policy `policy-1234567890abcdef0` are shared with your account.  
*Required*: No  
*Type*: String  
*Pattern*: `[\p{all}]*`  
*Minimum*: `0`  
*Maximum*: `1000`  
*Update requires*: [No interruption](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`EventType`  <a name="cfn-dlm-lifecyclepolicy-eventparameters-eventtype"></a>
The type of event. Currently, only snapshot sharing events are supported.  
*Required*: Yes  
*Type*: String  
*Allowed values*: `shareSnapshot`  
*Update requires*: [No interruption](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`SnapshotOwner`  <a name="cfn-dlm-lifecyclepolicy-eventparameters-snapshotowner"></a>
The IDs of the Amazon Web Services accounts that can trigger policy by sharing snapshots with your account. The policy only runs if one of the specified Amazon Web Services accounts shares a snapshot with your account.  
*Required*: Yes  
*Type*: Array of String  
*Minimum*: `0`  
*Maximum*: `50`  
*Update requires*: [No interruption](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)