# UpdateResolver
<a name="API_UpdateResolver"></a>

Updates a `Resolver` object.

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

```
POST /v1/apis/apiId/types/typeName/resolvers/fieldName HTTP/1.1
Content-type: application/json

{
   "cachingConfig": { 
      "cachingKeys": [ "string" ],
      "ttl": number
   },
   "code": "string",
   "dataSourceName": "string",
   "kind": "string",
   "maxBatchSize": number,
   "metricsConfig": "string",
   "pipelineConfig": { 
      "functions": [ "string" ]
   },
   "requestMappingTemplate": "string",
   "responseMappingTemplate": "string",
   "runtime": { 
      "name": "string",
      "runtimeVersion": "string"
   },
   "syncConfig": { 
      "conflictDetection": "string",
      "conflictHandler": "string",
      "lambdaConflictHandlerConfig": { 
         "lambdaConflictHandlerArn": "string"
      }
   }
}
```

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

The request uses the following URI parameters.

 ** [apiId](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-uri-apiId"></a>
The API ID.  
Required: Yes

 ** [fieldName](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-uri-fieldName"></a>
The new field name.  
Length Constraints: Minimum length of 1. Maximum length of 65536.  
Pattern: `[_A-Za-z][_0-9A-Za-z]*`   
Required: Yes

 ** [typeName](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-uri-typeName"></a>
The new type name.  
Length Constraints: Minimum length of 1. Maximum length of 65536.  
Pattern: `[_A-Za-z][_0-9A-Za-z]*`   
Required: Yes

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

The request accepts the following data in JSON format.

 ** [cachingConfig](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-cachingConfig"></a>
The caching configuration for the resolver.  
Type: [CachingConfig](API_CachingConfig.md) object  
Required: No

 ** [code](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-code"></a>
The `resolver` code that contains the request and response functions. When code is used, the `runtime` is required. The `runtime` value must be `APPSYNC_JS`.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 32768.  
Required: No

 ** [dataSourceName](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-dataSourceName"></a>
The new data source name.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 65536.  
Pattern: `[_A-Za-z][_0-9A-Za-z]*`   
Required: No

 ** [kind](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-kind"></a>
The resolver type.  
+  **UNIT**: A UNIT resolver type. A UNIT resolver is the default resolver type. You can use a UNIT resolver to run a GraphQL query against a single data source.
+  **PIPELINE**: A PIPELINE resolver type. You can use a PIPELINE resolver to invoke a series of `Function` objects in a serial manner. You can use a pipeline resolver to run a GraphQL query against multiple data sources.
Type: String  
Valid Values: `UNIT | PIPELINE`   
Required: No

 ** [maxBatchSize](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-maxBatchSize"></a>
The maximum batching size for a resolver.  
Type: Integer  
Valid Range: Minimum value of 0. Maximum value of 2000.  
Required: No

 ** [metricsConfig](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-metricsConfig"></a>
Enables or disables enhanced resolver metrics for specified resolvers. Note that `metricsConfig` won't be used unless the `resolverLevelMetricsBehavior` value is set to `PER_RESOLVER_METRICS`. If the `resolverLevelMetricsBehavior` is set to `FULL_REQUEST_RESOLVER_METRICS` instead, `metricsConfig` will be ignored. However, you can still set its value.  
 `metricsConfig` can be `ENABLED` or `DISABLED`.  
Type: String  
Valid Values: `ENABLED | DISABLED`   
Required: No

 ** [pipelineConfig](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-pipelineConfig"></a>
The `PipelineConfig`.  
Type: [PipelineConfig](API_PipelineConfig.md) object  
Required: No

 ** [requestMappingTemplate](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-requestMappingTemplate"></a>
The new request mapping template.  
A resolver uses a request mapping template to convert a GraphQL expression into a format that a data source can understand. Mapping templates are written in Apache Velocity Template Language (VTL).  
VTL request mapping templates are optional when using an AWS Lambda data source. For all other data sources, VTL request and response mapping templates are required.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 65536.  
Pattern: `^.*$`   
Required: No

 ** [responseMappingTemplate](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-responseMappingTemplate"></a>
The new response mapping template.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 65536.  
Pattern: `^.*$`   
Required: No

 ** [runtime](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-runtime"></a>
Describes a runtime used by an AWS AppSync pipeline resolver or AWS AppSync function. Specifies the name and version of the runtime to use. Note that if a runtime is specified, code must also be specified.  
Type: [AppSyncRuntime](API_AppSyncRuntime.md) object  
Required: No

 ** [syncConfig](#API_UpdateResolver_RequestSyntax) **   <a name="appsync-UpdateResolver-request-syncConfig"></a>
The `SyncConfig` for a resolver attached to a versioned data source.  
Type: [SyncConfig](API_SyncConfig.md) object  
Required: No

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

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

{
   "resolver": { 
      "cachingConfig": { 
         "cachingKeys": [ "string" ],
         "ttl": number
      },
      "code": "string",
      "dataSourceName": "string",
      "fieldName": "string",
      "kind": "string",
      "maxBatchSize": number,
      "metricsConfig": "string",
      "pipelineConfig": { 
         "functions": [ "string" ]
      },
      "requestMappingTemplate": "string",
      "resolverArn": "string",
      "responseMappingTemplate": "string",
      "runtime": { 
         "name": "string",
         "runtimeVersion": "string"
      },
      "syncConfig": { 
         "conflictDetection": "string",
         "conflictHandler": "string",
         "lambdaConflictHandlerConfig": { 
            "lambdaConflictHandlerArn": "string"
         }
      },
      "typeName": "string"
   }
}
```

## Response Elements
<a name="API_UpdateResolver_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.

 ** [resolver](#API_UpdateResolver_ResponseSyntax) **   <a name="appsync-UpdateResolver-response-resolver"></a>
The updated `Resolver` object.  
Type: [Resolver](API_Resolver.md) object

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

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

 ** BadRequestException **   
The request is not well formed. For example, a value is invalid or a required field is missing. Check the field values, and then try again.    
 ** detail **   
Provides further details for the reason behind the bad request. For reason type `CODE_ERROR`, the detail will contain a list of code errors.  
 ** reason **   
Provides context for the cause of the bad request. The only supported value is `CODE_ERROR`.
HTTP Status Code: 400

 ** ConcurrentModificationException **   
Another modification is in progress at this time and it must complete before you can make your change.  
HTTP Status Code: 409

 ** InternalFailureException **   
An internal AWS AppSync error occurred. Try your request again.  
HTTP Status Code: 500

 ** NotFoundException **   
The resource specified in the request was not found. Check the resource, and then try again.  
HTTP Status Code: 404

 ** UnauthorizedException **   
You aren't authorized to perform this operation.  
HTTP Status Code: 401

## See Also
<a name="API_UpdateResolver_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/appsync-2017-07-25/UpdateResolver) 
+  [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/appsync-2017-07-25/UpdateResolver) 
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/appsync-2017-07-25/UpdateResolver) 
+  [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/appsync-2017-07-25/UpdateResolver) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/appsync-2017-07-25/UpdateResolver) 
+  [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/appsync-2017-07-25/UpdateResolver) 
+  [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/appsync-2017-07-25/UpdateResolver) 
+  [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/appsync-2017-07-25/UpdateResolver) 
+  [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/appsync-2017-07-25/UpdateResolver) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/appsync-2017-07-25/UpdateResolver)