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# AWS::DevOpsGuru::ResourceCollection TagCollection
<a name="aws-properties-devopsguru-resourcecollection-tagcollection"></a>

A collection of Amazon tags.

Tags help you identify and organize your Amazon resources. Many Amazon services support tagging, so you can assign the same tag to resources from different services to indicate that the resources are related. For example, you can assign the same tag to an Amazon DynamoDB table resource that you assign to an Amazon Lambda function. For more information about using tags, see the [Tagging best practices](https://docs.amazonaws.cn/whitepapers/latest/tagging-best-practices/tagging-best-practices.html) whitepaper. 

Each Amazon tag has two parts. 
+ A tag *key* (for example, `CostCenter`, `Environment`, `Project`, or `Secret`). Tag *keys* are case-sensitive.
+ A field known as a tag *value* (for example, `111122223333`, `Production`, or a team name). Omitting the tag *value* is the same as using an empty string. Like tag *keys*, tag *values* are case-sensitive. The tag value is a required property when *AppBoundaryKey* is specified.

Together these are known as *key*-*value* pairs.

**Important**  
The string used for a *key* in a tag that you use to define your resource coverage must begin with the prefix `Devops-guru-`. The tag *key* might be `DevOps-Guru-deployment-application` or `devops-guru-rds-application`. When you create a *key*, the case of characters in the *key* can be whatever you choose. After you create a *key*, it is case-sensitive. For example, DevOps Guru works with a *key* named `devops-guru-rds` and a *key* named `DevOps-Guru-RDS`, and these act as two different *keys*. Possible *key*/*value* pairs in your application might be `Devops-Guru-production-application/RDS` or `Devops-Guru-production-application/containers`.

## Syntax
<a name="aws-properties-devopsguru-resourcecollection-tagcollection-syntax"></a>

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

### JSON
<a name="aws-properties-devopsguru-resourcecollection-tagcollection-syntax.json"></a>

```
{
  "[AppBoundaryKey](#cfn-devopsguru-resourcecollection-tagcollection-appboundarykey)" : {{String}},
  "[TagValues](#cfn-devopsguru-resourcecollection-tagcollection-tagvalues)" : {{[ String, ... ]}}
}
```

### YAML
<a name="aws-properties-devopsguru-resourcecollection-tagcollection-syntax.yaml"></a>

```
  [AppBoundaryKey](#cfn-devopsguru-resourcecollection-tagcollection-appboundarykey): {{String}}
  [TagValues](#cfn-devopsguru-resourcecollection-tagcollection-tagvalues): {{
    - String}}
```

## Properties
<a name="aws-properties-devopsguru-resourcecollection-tagcollection-properties"></a>

`AppBoundaryKey`  <a name="cfn-devopsguru-resourcecollection-tagcollection-appboundarykey"></a>
An Amazon tag *key* that is used to identify the Amazon resources that DevOps Guru analyzes. All Amazon resources in your account and Region tagged with this *key* make up your DevOps Guru application and analysis boundary.  
When you create a *key*, the case of characters in the *key* can be whatever you choose. After you create a *key*, it is case-sensitive. For example, DevOps Guru works with a *key* named `devops-guru-rds` and a *key* named `DevOps-Guru-RDS`, and these act as two different *keys*. Possible *key*/*value* pairs in your application might be `Devops-Guru-production-application/RDS` or `Devops-Guru-production-application/containers`.
*Required*: No  
*Type*: String  
*Minimum*: `1`  
*Maximum*: `128`  
*Update requires*: [No interruption](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`TagValues`  <a name="cfn-devopsguru-resourcecollection-tagcollection-tagvalues"></a>
The values in an Amazon tag collection.  
The tag's *value* is a field used to associate a string with the tag *key* (for example, `111122223333`, `Production`, or a team name). The *key* and *value* are the tag's *key* pair. Omitting the tag *value* is the same as using an empty string. Like tag *keys*, tag *values* are case-sensitive. You can specify a maximum of 256 characters for a tag value. The tag value is a required property when *AppBoundaryKey* is specified.  
*Required*: No  
*Type*: Array of String  
*Minimum*: `1 | 1`  
*Maximum*: `256 | 1000`  
*Update requires*: [No interruption](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)