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::IoT::Dimension
<a name="aws-resource-iot-dimension"></a>

Use the `AWS::IoT::Dimension` to limit the scope of a metric used in a security profile for AWS IoT Device Defender. For example, using a `TOPIC_FILTER` dimension, you can narrow down the scope of the metric to only MQTT topics where the name matches the pattern specified in the dimension. For API reference, see [CreateDimension](https://docs.aws.amazon.com/iot/latest/apireference/API_CreateDimension.html) and for general information, see [Scoping metrics in security profiles using dimensions](https://docs.aws.amazon.com/iot/latest/developerguide/scoping-security-behavior.html).

## Syntax
<a name="aws-resource-iot-dimension-syntax"></a>

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

### JSON
<a name="aws-resource-iot-dimension-syntax.json"></a>

```
{
  "Type" : "AWS::IoT::Dimension",
  "Properties" : {
      "[Name](#cfn-iot-dimension-name)" : String,
      "[StringValues](#cfn-iot-dimension-stringvalues)" : [ String, ... ],
      "[Tags](#cfn-iot-dimension-tags)" : [ Tag, ... ],
      "[Type](#cfn-iot-dimension-type)" : String
    }
}
```

### YAML
<a name="aws-resource-iot-dimension-syntax.yaml"></a>

```
Type: AWS::IoT::Dimension
Properties:
  [Name](#cfn-iot-dimension-name): String
  [StringValues](#cfn-iot-dimension-stringvalues): 
    - String
  [Tags](#cfn-iot-dimension-tags): 
    - Tag
  [Type](#cfn-iot-dimension-type): String
```

## Properties
<a name="aws-resource-iot-dimension-properties"></a>

`Name`  <a name="cfn-iot-dimension-name"></a>
A unique identifier for the dimension.  
*Required*: No  
*Type*: String  
*Pattern*: `[a-zA-Z0-9:_-]+`  
*Minimum*: `1`  
*Maximum*: `128`  
*Update requires*: [Replacement](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-replacement)

`StringValues`  <a name="cfn-iot-dimension-stringvalues"></a>
Specifies the value or list of values for the dimension. For `TOPIC_FILTER` dimensions, this is a pattern used to match the MQTT topic (for example, "admin/\$1").  
*Required*: Yes  
*Type*: Array of String  
*Minimum*: `1 | 1`  
*Maximum*: `256 | 5`  
*Update requires*: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`Tags`  <a name="cfn-iot-dimension-tags"></a>
Metadata that can be used to manage the dimension.  
*Required*: No  
*Type*: Array of [Tag](aws-properties-iot-dimension-tag.md)  
*Maximum*: `50`  
*Update requires*: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`Type`  <a name="cfn-iot-dimension-type"></a>
Specifies the type of dimension. Supported types: `TOPIC_FILTER.`  
*Required*: Yes  
*Type*: String  
*Allowed values*: `TOPIC_FILTER`  
*Update requires*: [Replacement](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-replacement)

## Return values
<a name="aws-resource-iot-dimension-return-values"></a>

### Ref
<a name="aws-resource-iot-dimension-return-values-ref"></a>

When you pass the logical ID of this resource to the intrinsic `Ref` function, `Ref` returns the dimension name.

### Fn::GetAtt
<a name="aws-resource-iot-dimension-return-values-fn--getatt"></a>

The `Fn::GetAtt` intrinsic function returns a value for a specified attribute of this type. The following are the available attributes and sample return values.

For more information about using the `Fn::GetAtt` intrinsic function, see [https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-getatt.html](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-getatt.html).

#### 
<a name="aws-resource-iot-dimension-return-values-fn--getatt-fn--getatt"></a>

`Arn`  <a name="Arn-fn::getatt"></a>
The Amazon Resource Name (ARN) of the dimension.

## Examples
<a name="aws-resource-iot-dimension--examples"></a>



### 
<a name="aws-resource-iot-dimension--examples--"></a>



#### JSON
<a name="aws-resource-iot-dimension--examples----json"></a>

```
{
  "AWSTemplateFormatVersion": "2010-09-09",
  "Description": "Amazon Web Services IoT Dimension Sample Template",
  "Resources": {
    "TopicFilterForAuthMessagesDimension": {
      "Type": "AWS::IoT::Dimension",
      "Properties": {
        "Name": "TopicFilterForAuthMessages",
        "Type": "TOPIC_FILTER",
        "StringValues": [
          "device/+/auth"
        ],
        "Tags": [
          {
            "Key": "Application",
            "Value": "SmartHome"
          }
        ]
      }
    }
  }
}
```

#### YAML
<a name="aws-resource-iot-dimension--examples----yaml"></a>

```
AWSTemplateFormatVersion: '2010-09-09'
Description: Amazon Web Services IoT Dimension Sample Template
Resources:
  TopicFilterForAuthMessagesDimension:
    Type: 'AWS::IoT::Dimension'
    Properties:
      Name: TopicFilterForAuthMessages
      Type: TOPIC_FILTER
      StringValues:
        - device/+/auth
      Tags:
        - Key: Application
          Value: SmartHome
```