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

# AWS::DynamoDB::Table StreamSpecification
<a name="aws-properties-dynamodb-table-streamspecification"></a>

Represents the DynamoDB Streams configuration for a table in DynamoDB.

## Syntax
<a name="aws-properties-dynamodb-table-streamspecification-syntax"></a>

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

### JSON
<a name="aws-properties-dynamodb-table-streamspecification-syntax.json"></a>

```
{
  "[ResourcePolicy](#cfn-dynamodb-table-streamspecification-resourcepolicy)" : ResourcePolicy,
  "[StreamViewType](#cfn-dynamodb-table-streamspecification-streamviewtype)" : String
}
```

### YAML
<a name="aws-properties-dynamodb-table-streamspecification-syntax.yaml"></a>

```
  [ResourcePolicy](#cfn-dynamodb-table-streamspecification-resourcepolicy): 
    ResourcePolicy
  [StreamViewType](#cfn-dynamodb-table-streamspecification-streamviewtype): String
```

## Properties
<a name="aws-properties-dynamodb-table-streamspecification-properties"></a>

`ResourcePolicy`  <a name="cfn-dynamodb-table-streamspecification-resourcepolicy"></a>
Creates or updates a resource-based policy document that contains the permissions for DynamoDB resources, such as a table's streams. Resource-based policies let you define access permissions by specifying who has access to each resource, and the actions they are allowed to perform on each resource.  
When you remove the `StreamSpecification` property from the template, DynamoDB disables the stream but retains any attached resource policy until the stream is deleted after 24 hours. When you modify the `StreamViewType` property, DynamoDB creates a new stream and retains the old stream's resource policy. The old stream and its resource policy are deleted after the 24-hour retention period.
In a CloudFormation template, you can provide the policy in JSON or YAML format because CloudFormation converts YAML to JSON before submitting it to DynamoDB. For more information about resource-based policies, see [Using resource-based policies for DynamoDB](https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/access-control-resource-based.html) and [Resource-based policy examples](https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/rbac-examples.html).  
*Required*: No  
*Type*: [ResourcePolicy](aws-properties-dynamodb-table-resourcepolicy.md)  
*Update requires*: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`StreamViewType`  <a name="cfn-dynamodb-table-streamspecification-streamviewtype"></a>
 When an item in the table is modified, `StreamViewType` determines what information is written to the stream for this table. Valid values for `StreamViewType` are:  
+ `KEYS_ONLY` - Only the key attributes of the modified item are written to the stream.
+ `NEW_IMAGE` - The entire item, as it appears after it was modified, is written to the stream.
+ `OLD_IMAGE` - The entire item, as it appeared before it was modified, is written to the stream.
+ `NEW_AND_OLD_IMAGES` - Both the new and the old item images of the item are written to the stream.
*Required*: Yes  
*Type*: String  
*Allowed values*: `NEW_IMAGE | OLD_IMAGE | NEW_AND_OLD_IMAGES | KEYS_ONLY`  
*Update requires*: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)