# GetLensVersionDifference
<a name="API_GetLensVersionDifference"></a>

Get lens version differences.

## Request Syntax
<a name="API_GetLensVersionDifference_RequestSyntax"></a>

```
GET /lenses/LensAlias/versionDifference?BaseLensVersion=BaseLensVersion&TargetLensVersion=TargetLensVersion HTTP/1.1
```

## URI Request Parameters
<a name="API_GetLensVersionDifference_RequestParameters"></a>

The request uses the following URI parameters.

 ** [BaseLensVersion](#API_GetLensVersionDifference_RequestSyntax) **   <a name="wellarchitected-GetLensVersionDifference-request-uri-BaseLensVersion"></a>
The base version of the lens.  
Length Constraints: Minimum length of 1. Maximum length of 32.

 ** [LensAlias](#API_GetLensVersionDifference_RequestSyntax) **   <a name="wellarchitected-GetLensVersionDifference-request-uri-LensAlias"></a>
The alias of the lens.  
For AWS official lenses, this is either the lens alias, such as `serverless`, or the lens ARN, such as `arn:aws:wellarchitected:us-east-1::lens/serverless`. Note that some operations (such as ExportLens and CreateLensShare) are not permitted on AWS official lenses.  
For custom lenses, this is the lens ARN, such as `arn:aws:wellarchitected:us-west-2:123456789012:lens/0123456789abcdef01234567890abcdef`.   
Each lens is identified by its [LensSummary:LensAlias](API_LensSummary.md#wellarchitected-Type-LensSummary-LensAlias).  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Required: Yes

 ** [TargetLensVersion](#API_GetLensVersionDifference_RequestSyntax) **   <a name="wellarchitected-GetLensVersionDifference-request-uri-TargetLensVersion"></a>
The lens version to target a difference for.  
Length Constraints: Minimum length of 1. Maximum length of 32.

## Request Body
<a name="API_GetLensVersionDifference_RequestBody"></a>

The request does not have a request body.

## Response Syntax
<a name="API_GetLensVersionDifference_ResponseSyntax"></a>

```
HTTP/1.1 200
Content-type: application/json

{
   "BaseLensVersion": "string",
   "LatestLensVersion": "string",
   "LensAlias": "string",
   "LensArn": "string",
   "TargetLensVersion": "string",
   "VersionDifferences": { 
      "PillarDifferences": [ 
         { 
            "DifferenceStatus": "string",
            "PillarId": "string",
            "PillarName": "string",
            "QuestionDifferences": [ 
               { 
                  "DifferenceStatus": "string",
                  "QuestionId": "string",
                  "QuestionTitle": "string"
               }
            ]
         }
      ]
   }
}
```

## Response Elements
<a name="API_GetLensVersionDifference_ResponseElements"></a>

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.

 ** [BaseLensVersion](#API_GetLensVersionDifference_ResponseSyntax) **   <a name="wellarchitected-GetLensVersionDifference-response-BaseLensVersion"></a>
The base version of the lens.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 32.

 ** [LatestLensVersion](#API_GetLensVersionDifference_ResponseSyntax) **   <a name="wellarchitected-GetLensVersionDifference-response-LatestLensVersion"></a>
The latest version of the lens.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 32.

 ** [LensAlias](#API_GetLensVersionDifference_ResponseSyntax) **   <a name="wellarchitected-GetLensVersionDifference-response-LensAlias"></a>
The alias of the lens.  
For AWS official lenses, this is either the lens alias, such as `serverless`, or the lens ARN, such as `arn:aws:wellarchitected:us-east-1::lens/serverless`. Note that some operations (such as ExportLens and CreateLensShare) are not permitted on AWS official lenses.  
For custom lenses, this is the lens ARN, such as `arn:aws:wellarchitected:us-west-2:123456789012:lens/0123456789abcdef01234567890abcdef`.   
Each lens is identified by its [LensSummary:LensAlias](API_LensSummary.md#wellarchitected-Type-LensSummary-LensAlias).  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.

 ** [LensArn](#API_GetLensVersionDifference_ResponseSyntax) **   <a name="wellarchitected-GetLensVersionDifference-response-LensArn"></a>
The ARN for the lens.  
Type: String

 ** [TargetLensVersion](#API_GetLensVersionDifference_ResponseSyntax) **   <a name="wellarchitected-GetLensVersionDifference-response-TargetLensVersion"></a>
The target lens version for the lens.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 32.

 ** [VersionDifferences](#API_GetLensVersionDifference_ResponseSyntax) **   <a name="wellarchitected-GetLensVersionDifference-response-VersionDifferences"></a>
The differences between the base and latest versions of the lens.  
Type: [VersionDifferences](API_VersionDifferences.md) object

## Errors
<a name="API_GetLensVersionDifference_Errors"></a>

For information about the errors that are common to all actions, see [Common Error Types](CommonErrors.md).

 ** AccessDeniedException **   
User does not have sufficient access to perform this action.    
 ** Message **   
Description of the error.
HTTP Status Code: 403

 ** InternalServerException **   
There is a problem with the AWS Well-Architected Tool API service.    
 ** Message **   
Description of the error.
HTTP Status Code: 500

 ** ResourceNotFoundException **   
The requested resource was not found.    
 ** Message **   
Description of the error.  
 ** ResourceId **   
Identifier of the resource affected.  
 ** ResourceType **   
Type of the resource affected.
HTTP Status Code: 404

 ** ThrottlingException **   
Request was denied due to request throttling.    
 ** Message **   
Description of the error.  
 ** QuotaCode **   
Service Quotas requirement to identify originating quota.  
 ** ServiceCode **   
Service Quotas requirement to identify originating service.
HTTP Status Code: 429

 ** ValidationException **   
The user input is not valid.    
 ** Fields **   
The fields that caused the error, if applicable.  
 ** Message **   
Description of the error.  
 ** Reason **   
The reason why the request failed validation.
HTTP Status Code: 400

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

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS Command Line Interface V2](https://docs.aws.amazon.com/goto/cli2/wellarchitected-2020-03-31/GetLensVersionDifference) 
+  [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/wellarchitected-2020-03-31/GetLensVersionDifference) 
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/wellarchitected-2020-03-31/GetLensVersionDifference) 
+  [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/wellarchitected-2020-03-31/GetLensVersionDifference) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/wellarchitected-2020-03-31/GetLensVersionDifference) 
+  [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/wellarchitected-2020-03-31/GetLensVersionDifference) 
+  [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/wellarchitected-2020-03-31/GetLensVersionDifference) 
+  [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/wellarchitected-2020-03-31/GetLensVersionDifference) 
+  [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/wellarchitected-2020-03-31/GetLensVersionDifference) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/wellarchitected-2020-03-31/GetLensVersionDifference)