# UpdateByteMatchSet
<a name="API_wafRegional_UpdateByteMatchSet"></a>

**Note**  
 Amazon WAF Classic support will end on September 30, 2025.   
This is ** Amazon WAF Classic** documentation. For more information, see [Amazon WAF Classic](https://docs.amazonaws.cn/waf/latest/developerguide/classic-waf-chapter.html) in the developer guide.  
 **For the latest version of Amazon WAF **, use the Amazon WAFV2 API and see the [Amazon WAF Developer Guide](https://docs.amazonaws.cn/waf/latest/developerguide/waf-chapter.html). With the latest version, Amazon WAF has a single set of endpoints for regional and global use. 

Inserts or deletes [ByteMatchTuple](API_wafRegional_ByteMatchTuple.md) objects (filters) in a [ByteMatchSet](API_wafRegional_ByteMatchSet.md). For each `ByteMatchTuple` object, you specify the following values: 
+ Whether to insert or delete the object from the array. If you want to change a `ByteMatchSetUpdate` object, you delete the existing object and add a new one.
+ The part of a web request that you want Amazon WAF to inspect, such as a query string or the value of the `User-Agent` header. 
+ The bytes (typically a string that corresponds with ASCII characters) that you want Amazon WAF to look for. For more information, including how you specify the values for the Amazon WAF API and the Amazon CLI or Amazon SDKs, see `TargetString` in the [ByteMatchTuple](API_wafRegional_ByteMatchTuple.md) data type. 
+ Where to look, such as at the beginning or the end of a query string.
+ Whether to perform any conversions on the request, such as converting it to lowercase, before inspecting it for the specified string.

For example, you can add a `ByteMatchSetUpdate` object that matches web requests in which `User-Agent` headers contain the string `BadBot`. You can then configure Amazon WAF to block those requests.

To create and configure a `ByteMatchSet`, perform the following steps:

1. Create a `ByteMatchSet.` For more information, see [CreateByteMatchSet](API_wafRegional_CreateByteMatchSet.md).

1. Use [GetChangeToken](API_wafRegional_GetChangeToken.md) to get the change token that you provide in the `ChangeToken` parameter of an `UpdateByteMatchSet` request.

1. Submit an `UpdateByteMatchSet` request to specify the part of the request that you want Amazon WAF to inspect (for example, the header or the URI path) and the value that you want Amazon WAF to watch for.

For more information about how to use the Amazon WAF API to allow or block HTTP requests, see the [Amazon WAF Developer Guide](https://docs.amazonaws.cn/waf/latest/developerguide/).

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

```
{
   "ByteMatchSetId": "string",
   "ChangeToken": "string",
   "Updates": [ 
      { 
         "Action": "string",
         "ByteMatchTuple": { 
            "FieldToMatch": { 
               "Data": "string",
               "Type": "string"
            },
            "PositionalConstraint": "string",
            "TargetString": blob,
            "TextTransformation": "string"
         }
      }
   ]
}
```

## Request Parameters
<a name="API_wafRegional_UpdateByteMatchSet_RequestParameters"></a>

For information about the parameters that are common to all actions, see [Common Parameters](CommonParameters.md).

The request accepts the following data in JSON format.

 ** [ByteMatchSetId](#API_wafRegional_UpdateByteMatchSet_RequestSyntax) **   <a name="WAF-wafRegional_UpdateByteMatchSet-request-ByteMatchSetId"></a>
The `ByteMatchSetId` of the [ByteMatchSet](API_wafRegional_ByteMatchSet.md) that you want to update. `ByteMatchSetId` is returned by [CreateByteMatchSet](API_wafRegional_CreateByteMatchSet.md) and by [ListByteMatchSets](API_wafRegional_ListByteMatchSets.md).  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Pattern: `.*\S.*`   
Required: Yes

 ** [ChangeToken](#API_wafRegional_UpdateByteMatchSet_RequestSyntax) **   <a name="WAF-wafRegional_UpdateByteMatchSet-request-ChangeToken"></a>
The value returned by the most recent call to [GetChangeToken](API_wafRegional_GetChangeToken.md).  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Pattern: `.*\S.*`   
Required: Yes

 ** [Updates](#API_wafRegional_UpdateByteMatchSet_RequestSyntax) **   <a name="WAF-wafRegional_UpdateByteMatchSet-request-Updates"></a>
An array of `ByteMatchSetUpdate` objects that you want to insert into or delete from a [ByteMatchSet](API_wafRegional_ByteMatchSet.md). For more information, see the applicable data types:  
+  [ByteMatchSetUpdate](API_wafRegional_ByteMatchSetUpdate.md): Contains `Action` and `ByteMatchTuple` 
+  [ByteMatchTuple](API_wafRegional_ByteMatchTuple.md): Contains `FieldToMatch`, `PositionalConstraint`, `TargetString`, and `TextTransformation` 
+  [FieldToMatch](API_wafRegional_FieldToMatch.md): Contains `Data` and `Type` 
Type: Array of [ByteMatchSetUpdate](API_wafRegional_ByteMatchSetUpdate.md) objects  
Array Members: Minimum number of 1 item.  
Required: Yes

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

```
{
   "ChangeToken": "string"
}
```

## Response Elements
<a name="API_wafRegional_UpdateByteMatchSet_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.

 ** [ChangeToken](#API_wafRegional_UpdateByteMatchSet_ResponseSyntax) **   <a name="WAF-wafRegional_UpdateByteMatchSet-response-ChangeToken"></a>
The `ChangeToken` that you used to submit the `UpdateByteMatchSet` request. You can also use this value to query the status of the request. For more information, see [GetChangeTokenStatus](API_wafRegional_GetChangeTokenStatus.md).  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Pattern: `.*\S.*` 

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

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

 ** WAFInternalErrorException **   
The operation failed because of a system problem, even though the request was valid. Retry your request.  
HTTP Status Code: 500

 ** WAFInvalidAccountException **   
The operation failed because you tried to create, update, or delete an object by using an invalid account identifier.  
HTTP Status Code: 400

 ** WAFInvalidOperationException **   
The operation failed because there was nothing to do. For example:  
+ You tried to remove a `Rule` from a `WebACL`, but the `Rule` isn't in the specified `WebACL`.
+ You tried to remove an IP address from an `IPSet`, but the IP address isn't in the specified `IPSet`.
+ You tried to remove a `ByteMatchTuple` from a `ByteMatchSet`, but the `ByteMatchTuple` isn't in the specified `WebACL`.
+ You tried to add a `Rule` to a `WebACL`, but the `Rule` already exists in the specified `WebACL`.
+ You tried to add a `ByteMatchTuple` to a `ByteMatchSet`, but the `ByteMatchTuple` already exists in the specified `WebACL`.
HTTP Status Code: 400

 ** WAFInvalidParameterException **   
The operation failed because Amazon WAF didn't recognize a parameter in the request. For example:  
+ You specified an invalid parameter name.
+ You specified an invalid value.
+ You tried to update an object (`ByteMatchSet`, `IPSet`, `Rule`, or `WebACL`) using an action other than `INSERT` or `DELETE`.
+ You tried to create a `WebACL` with a `DefaultAction` `Type` other than `ALLOW`, `BLOCK`, or `COUNT`.
+ You tried to create a `RateBasedRule` with a `RateKey` value other than `IP`.
+ You tried to update a `WebACL` with a `WafAction` `Type` other than `ALLOW`, `BLOCK`, or `COUNT`.
+ You tried to update a `ByteMatchSet` with a `FieldToMatch` `Type` other than HEADER, METHOD, QUERY\$1STRING, URI, or BODY.
+ You tried to update a `ByteMatchSet` with a `Field` of `HEADER` but no value for `Data`.
+ Your request references an ARN that is malformed, or corresponds to a resource with which a web ACL cannot be associated.
HTTP Status Code: 400

 ** WAFLimitsExceededException **   
The operation exceeds a resource limit, for example, the maximum number of `WebACL` objects that you can create for an Amazon Web Services account. For more information, see [Amazon WAF Classic quotas](https://docs.amazonaws.cn/waf/latest/developerguide/classic-limits.html) in the * Amazon WAF Developer Guide*.  
HTTP Status Code: 400

 ** WAFNonexistentContainerException **   
The operation failed because you tried to add an object to or delete an object from another object that doesn't exist. For example:  
+ You tried to add a `Rule` to or delete a `Rule` from a `WebACL` that doesn't exist.
+ You tried to add a `ByteMatchSet` to or delete a `ByteMatchSet` from a `Rule` that doesn't exist.
+ You tried to add an IP address to or delete an IP address from an `IPSet` that doesn't exist.
+ You tried to add a `ByteMatchTuple` to or delete a `ByteMatchTuple` from a `ByteMatchSet` that doesn't exist.
HTTP Status Code: 400

 ** WAFNonexistentItemException **   
The operation failed because the referenced object doesn't exist.  
HTTP Status Code: 400

 ** WAFStaleDataException **   
The operation failed because you tried to create, update, or delete an object by using a change token that has already been used.  
HTTP Status Code: 400

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

For more information about using this API in one of the language-specific Amazon SDKs, see the following:
+  [Amazon Command Line Interface V2](https://docs.amazonaws.cn/goto/cli2/waf-regional-2016-11-28/UpdateByteMatchSet) 
+  [Amazon SDK for .NET V4](https://docs.amazonaws.cn/goto/DotNetSDKV4/waf-regional-2016-11-28/UpdateByteMatchSet) 
+  [Amazon SDK for C\$1\$1](https://docs.amazonaws.cn/goto/SdkForCpp/waf-regional-2016-11-28/UpdateByteMatchSet) 
+  [Amazon SDK for Go v2](https://docs.amazonaws.cn/goto/SdkForGoV2/waf-regional-2016-11-28/UpdateByteMatchSet) 
+  [Amazon SDK for Java V2](https://docs.amazonaws.cn/goto/SdkForJavaV2/waf-regional-2016-11-28/UpdateByteMatchSet) 
+  [Amazon SDK for JavaScript V3](https://docs.amazonaws.cn/goto/SdkForJavaScriptV3/waf-regional-2016-11-28/UpdateByteMatchSet) 
+  [Amazon SDK for Kotlin](https://docs.amazonaws.cn/goto/SdkForKotlin/waf-regional-2016-11-28/UpdateByteMatchSet) 
+  [Amazon SDK for PHP V3](https://docs.amazonaws.cn/goto/SdkForPHPV3/waf-regional-2016-11-28/UpdateByteMatchSet) 
+  [Amazon SDK for Python](https://docs.amazonaws.cn/goto/boto3/waf-regional-2016-11-28/UpdateByteMatchSet) 
+  [Amazon SDK for Ruby V3](https://docs.amazonaws.cn/goto/SdkForRubyV3/waf-regional-2016-11-28/UpdateByteMatchSet)