# Principal
<a name="API_Principal"></a>

The IAM principal that you allowing or denying access to an Amazon Lex action. You must provide a `service` or an `arn`, but not both in the same statement. For more information, see [ AWS JSON policy elements: Principal ](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_principal.html).

## Contents
<a name="API_Principal_Contents"></a>

 ** arn **   <a name="lexv2-Type-Principal-arn"></a>
The Amazon Resource Name (ARN) of the principal.  
Type: String  
Length Constraints: Minimum length of 30. Maximum length of 1024.  
Pattern: `^arn:aws:iam::[0-9]{12}:(root|(user|role)/.*)$`   
Required: No

 ** service **   <a name="lexv2-Type-Principal-service"></a>
The name of the AWS service that should allowed or denied access to an Amazon Lex action.  
Type: String  
Length Constraints: Minimum length of 15. Maximum length of 1024.  
Pattern: `^[0-9a-zA-Z_.]+$`   
Required: No

## See Also
<a name="API_Principal_SeeAlso"></a>

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/models.lex.v2-2020-08-07/Principal) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/models.lex.v2-2020-08-07/Principal) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/models.lex.v2-2020-08-07/Principal)