:doc:`WAF <../../waf>` / Client / update_byte_match_set

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update_byte_match_set
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.. py:method:: WAF.Client.update_byte_match_set(**kwargs)

  

  .. note::

    

    This is **AWS WAF Classic** documentation. For more information, see `AWS WAF Classic <https://docs.aws.amazon.com/waf/latest/developerguide/classic-waf-chapter.html>`__ in the developer guide.

     

    **For the latest version of AWS WAF**, use the AWS WAFV2 API and see the `AWS WAF Developer Guide <https://docs.aws.amazon.com/waf/latest/developerguide/waf-chapter.html>`__. With the latest version, AWS WAF has a single set of endpoints for regional and global use.

    

   

  Inserts or deletes  ByteMatchTuple objects (filters) in a  ByteMatchSet. 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 AWS 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 AWS WAF to look for. For more information, including how you specify the values for the AWS WAF API and the AWS CLI or SDKs, see ``TargetString`` in the  ByteMatchTuple 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 AWS WAF to block those requests.

   

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

   

   
  * Create a ``ByteMatchSet.`` For more information, see  CreateByteMatchSet.
   
  * Use  GetChangeToken to get the change token that you provide in the ``ChangeToken`` parameter of an ``UpdateByteMatchSet`` request.
   
  * Submit an ``UpdateByteMatchSet`` request to specify the part of the request that you want AWS WAF to inspect (for example, the header or the URI) and the value that you want AWS WAF to watch for.
   

   

  For more information about how to use the AWS WAF API to allow or block HTTP requests, see the `AWS WAF Developer Guide <https://docs.aws.amazon.com/waf/latest/developerguide/>`__.

  

  See also: `AWS API Documentation <https://docs.aws.amazon.com/goto/WebAPI/waf-2015-08-24/UpdateByteMatchSet>`_  


  **Request Syntax**
  ::

    response = client.update_byte_match_set(
        ByteMatchSetId='string',
        ChangeToken='string',
        Updates=[
            {
                'Action': 'INSERT'|'DELETE',
                'ByteMatchTuple': {
                    'FieldToMatch': {
                        'Type': 'URI'|'QUERY_STRING'|'HEADER'|'METHOD'|'BODY'|'SINGLE_QUERY_ARG'|'ALL_QUERY_ARGS',
                        'Data': 'string'
                    },
                    'TargetString': b'bytes',
                    'TextTransformation': 'NONE'|'COMPRESS_WHITE_SPACE'|'HTML_ENTITY_DECODE'|'LOWERCASE'|'CMD_LINE'|'URL_DECODE',
                    'PositionalConstraint': 'EXACTLY'|'STARTS_WITH'|'ENDS_WITH'|'CONTAINS'|'CONTAINS_WORD'
                }
            },
        ]
    )
    
  :type ByteMatchSetId: string
  :param ByteMatchSetId: **[REQUIRED]** 

    The ``ByteMatchSetId`` of the  ByteMatchSet that you want to update. ``ByteMatchSetId`` is returned by  CreateByteMatchSet and by  ListByteMatchSets.

    

  
  :type ChangeToken: string
  :param ChangeToken: **[REQUIRED]** 

    The value returned by the most recent call to  GetChangeToken.

    

  
  :type Updates: list
  :param Updates: **[REQUIRED]** 

    An array of ``ByteMatchSetUpdate`` objects that you want to insert into or delete from a  ByteMatchSet. For more information, see the applicable data types:

     

    
    *  ByteMatchSetUpdate: Contains ``Action`` and ``ByteMatchTuple``
     
    *  ByteMatchTuple: Contains ``FieldToMatch``, ``PositionalConstraint``, ``TargetString``, and ``TextTransformation``
     
    *  FieldToMatch: Contains ``Data`` and ``Type``
    

    

  
    - *(dict) --* 

      .. note::

        

        This is **AWS WAF Classic** documentation. For more information, see `AWS WAF Classic <https://docs.aws.amazon.com/waf/latest/developerguide/classic-waf-chapter.html>`__ in the developer guide.

         

        **For the latest version of AWS WAF**, use the AWS WAFV2 API and see the `AWS WAF Developer Guide <https://docs.aws.amazon.com/waf/latest/developerguide/waf-chapter.html>`__. With the latest version, AWS WAF has a single set of endpoints for regional and global use.

        

       

      In an  UpdateByteMatchSet request, ``ByteMatchSetUpdate`` specifies whether to insert or delete a  ByteMatchTuple and includes the settings for the ``ByteMatchTuple``.

      

    
      - **Action** *(string) --* **[REQUIRED]** 

        Specifies whether to insert or delete a  ByteMatchTuple.

        

      
      - **ByteMatchTuple** *(dict) --* **[REQUIRED]** 

        Information about the part of a web request that you want AWS WAF to inspect and the value that you want AWS WAF to search for. If you specify ``DELETE`` for the value of ``Action``, the ``ByteMatchTuple`` values must exactly match the values in the ``ByteMatchTuple`` that you want to delete from the ``ByteMatchSet``.

        

      
        - **FieldToMatch** *(dict) --* **[REQUIRED]** 

          The part of a web request that you want AWS WAF to search, such as a specified header or a query string. For more information, see  FieldToMatch.

          

        
          - **Type** *(string) --* **[REQUIRED]** 

            The part of the web request that you want AWS WAF to search for a specified string. Parts of a request that you can search include the following:

             

            
            * ``HEADER``: A specified request header, for example, the value of the ``User-Agent`` or ``Referer`` header. If you choose ``HEADER`` for the type, specify the name of the header in ``Data``.
             
            * ``METHOD``: The HTTP method, which indicated the type of operation that the request is asking the origin to perform. Amazon CloudFront supports the following methods: ``DELETE``, ``GET``, ``HEAD``, ``OPTIONS``, ``PATCH``, ``POST``, and ``PUT``.
             
            * ``QUERY_STRING``: A query string, which is the part of a URL that appears after a ``?`` character, if any.
             
            * ``URI``: The part of a web request that identifies a resource, for example, ``/images/daily-ad.jpg``.
             
            * ``BODY``: The part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form. The request body immediately follows the request headers. Note that only the first ``8192`` bytes of the request body are forwarded to AWS WAF for inspection. To allow or block requests based on the length of the body, you can create a size constraint set. For more information, see  CreateSizeConstraintSet.
             
            * ``SINGLE_QUERY_ARG``: The parameter in the query string that you will inspect, such as *UserName* or *SalesRegion*. The maximum length for ``SINGLE_QUERY_ARG`` is 30 characters.
             
            * ``ALL_QUERY_ARGS``: Similar to ``SINGLE_QUERY_ARG``, but rather than inspecting a single parameter, AWS WAF will inspect all parameters within the query for the value or regex pattern that you specify in ``TargetString``.
            

            

          
          - **Data** *(string) --* 

            When the value of ``Type`` is ``HEADER``, enter the name of the header that you want AWS WAF to search, for example, ``User-Agent`` or ``Referer``. The name of the header is not case sensitive.

             

            When the value of ``Type`` is ``SINGLE_QUERY_ARG``, enter the name of the parameter that you want AWS WAF to search, for example, ``UserName`` or ``SalesRegion``. The parameter name is not case sensitive.

             

            If the value of ``Type`` is any other value, omit ``Data``.

            

          
        
        - **TargetString** *(bytes) --* **[REQUIRED]** 

          The value that you want AWS WAF to search for. AWS WAF searches for the specified string in the part of web requests that you specified in ``FieldToMatch``. The maximum length of the value is 50 bytes.

           

          Valid values depend on the values that you specified for ``FieldToMatch``:

           

          
          * ``HEADER``: The value that you want AWS WAF to search for in the request header that you specified in  FieldToMatch, for example, the value of the ``User-Agent`` or ``Referer`` header.
           
          * ``METHOD``: The HTTP method, which indicates the type of operation specified in the request. CloudFront supports the following methods: ``DELETE``, ``GET``, ``HEAD``, ``OPTIONS``, ``PATCH``, ``POST``, and ``PUT``.
           
          * ``QUERY_STRING``: The value that you want AWS WAF to search for in the query string, which is the part of a URL that appears after a ``?`` character.
           
          * ``URI``: The value that you want AWS WAF to search for in the part of a URL that identifies a resource, for example, ``/images/daily-ad.jpg``.
           
          * ``BODY``: The part of a request that contains any additional data that you want to send to your web server as the HTTP request body, such as data from a form. The request body immediately follows the request headers. Note that only the first ``8192`` bytes of the request body are forwarded to AWS WAF for inspection. To allow or block requests based on the length of the body, you can create a size constraint set. For more information, see  CreateSizeConstraintSet.
           
          * ``SINGLE_QUERY_ARG``: The parameter in the query string that you will inspect, such as *UserName* or *SalesRegion*. The maximum length for ``SINGLE_QUERY_ARG`` is 30 characters.
           
          * ``ALL_QUERY_ARGS``: Similar to ``SINGLE_QUERY_ARG``, but instead of inspecting a single parameter, AWS WAF inspects all parameters within the query string for the value or regex pattern that you specify in ``TargetString``.
          

           

          If ``TargetString`` includes alphabetic characters A-Z and a-z, note that the value is case sensitive.

           

          **If you're using the AWS WAF API**

           

          Specify a base64-encoded version of the value. The maximum length of the value before you base64-encode it is 50 bytes.

           

          For example, suppose the value of ``Type`` is ``HEADER`` and the value of ``Data`` is ``User-Agent``. If you want to search the ``User-Agent`` header for the value ``BadBot``, you base64-encode ``BadBot`` using MIME base64-encoding and include the resulting value, ``QmFkQm90``, in the value of ``TargetString``.

           

          **If you're using the AWS CLI or one of the AWS SDKs**

           

          The value that you want AWS WAF to search for. The SDK automatically base64 encodes the value.

          

        
        - **TextTransformation** *(string) --* **[REQUIRED]** 

          Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass AWS WAF. If you specify a transformation, AWS WAF performs the transformation on ``FieldToMatch`` before inspecting it for a match.

           

          You can only specify a single type of TextTransformation.

           

          **CMD_LINE**

           

          When you're concerned that attackers are injecting an operating system command line command and using unusual formatting to disguise some or all of the command, use this option to perform the following transformations:

           

          
          * Delete the following characters: \ " ' ^
           
          * Delete spaces before the following characters: / (
           
          * Replace the following characters with a space: , ;
           
          * Replace multiple spaces with one space
           
          * Convert uppercase letters (A-Z) to lowercase (a-z)
          

           

          **COMPRESS_WHITE_SPACE**

           

          Use this option to replace the following characters with a space character (decimal 32):

           

          
          * \f, formfeed, decimal 12
           
          * \t, tab, decimal 9
           
          * \n, newline, decimal 10
           
          * \r, carriage return, decimal 13
           
          * \v, vertical tab, decimal 11
           
          * non-breaking space, decimal 160
          

           

          ``COMPRESS_WHITE_SPACE`` also replaces multiple spaces with one space.

           

          **HTML_ENTITY_DECODE**

           

          Use this option to replace HTML-encoded characters with unencoded characters. ``HTML_ENTITY_DECODE`` performs the following operations:

           

          
          * Replaces ``(ampersand)quot;`` with ``"``
           
          * Replaces ``(ampersand)nbsp;`` with a non-breaking space, decimal 160
           
          * Replaces ``(ampersand)lt;`` with a "less than" symbol
           
          * Replaces ``(ampersand)gt;`` with ``>``
           
          * Replaces characters that are represented in hexadecimal format, ``(ampersand)#xhhhh;``, with the corresponding characters
           
          * Replaces characters that are represented in decimal format, ``(ampersand)#nnnn;``, with the corresponding characters
          

           

          **LOWERCASE**

           

          Use this option to convert uppercase letters (A-Z) to lowercase (a-z).

           

          **URL_DECODE**

           

          Use this option to decode a URL-encoded value.

           

          **NONE**

           

          Specify ``NONE`` if you don't want to perform any text transformations.

          

        
        - **PositionalConstraint** *(string) --* **[REQUIRED]** 

          Within the portion of a web request that you want to search (for example, in the query string, if any), specify where you want AWS WAF to search. Valid values include the following:

           

          **CONTAINS**

           

          The specified part of the web request must include the value of ``TargetString``, but the location doesn't matter.

           

          **CONTAINS_WORD**

           

          The specified part of the web request must include the value of ``TargetString``, and ``TargetString`` must contain only alphanumeric characters or underscore (A-Z, a-z, 0-9, or _). In addition, ``TargetString`` must be a word, which means one of the following:

           

          
          * ``TargetString`` exactly matches the value of the specified part of the web request, such as the value of a header.
           
          * ``TargetString`` is at the beginning of the specified part of the web request and is followed by a character other than an alphanumeric character or underscore (_), for example, ``BadBot;``.
           
          * ``TargetString`` is at the end of the specified part of the web request and is preceded by a character other than an alphanumeric character or underscore (_), for example, ``;BadBot``.
           
          * ``TargetString`` is in the middle of the specified part of the web request and is preceded and followed by characters other than alphanumeric characters or underscore (_), for example, ``-BadBot;``.
          

           

          **EXACTLY**

           

          The value of the specified part of the web request must exactly match the value of ``TargetString``.

           

          **STARTS_WITH**

           

          The value of ``TargetString`` must appear at the beginning of the specified part of the web request.

           

          **ENDS_WITH**

           

          The value of ``TargetString`` must appear at the end of the specified part of the web request.

          

        
      
    

  
  :rtype: dict
  :returns: 
    
    **Response Syntax**

    
    ::

      {
          'ChangeToken': 'string'
      }
      
    **Response Structure**

    

    - *(dict) --* 
      

      - **ChangeToken** *(string) --* 

        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.

        
  
  **Exceptions**
  
  *   :py:class:`WAF.Client.exceptions.WAFInternalErrorException`

  
  *   :py:class:`WAF.Client.exceptions.WAFInvalidAccountException`

  
  *   :py:class:`WAF.Client.exceptions.WAFInvalidOperationException`

  
  *   :py:class:`WAF.Client.exceptions.WAFInvalidParameterException`

  
  *   :py:class:`WAF.Client.exceptions.WAFNonexistentContainerException`

  
  *   :py:class:`WAF.Client.exceptions.WAFNonexistentItemException`

  
  *   :py:class:`WAF.Client.exceptions.WAFStaleDataException`

  
  *   :py:class:`WAF.Client.exceptions.WAFLimitsExceededException`

  

  **Examples**

  The following example deletes a ByteMatchTuple object (filters) in an byte match set with the ID exampleIDs3t-46da-4fdb-b8d5-abc321j569j5.
  ::

    response = client.update_byte_match_set(
        ByteMatchSetId='exampleIDs3t-46da-4fdb-b8d5-abc321j569j5',
        ChangeToken='abcd12f2-46da-4fdb-b8d5-fbd4c466928f',
        Updates=[
            {
                'Action': 'DELETE',
                'ByteMatchTuple': {
                    'FieldToMatch': {
                        'Data': 'referer',
                        'Type': 'HEADER',
                    },
                    'PositionalConstraint': 'CONTAINS',
                    'TargetString': 'badrefer1',
                    'TextTransformation': 'NONE',
                },
            },
        ],
    )
    
    print(response)

  
  Expected Output:
  ::

    {
        'ChangeToken': 'abcd12f2-46da-4fdb-b8d5-fbd4c466928f',
        'ResponseMetadata': {
            '...': '...',
        },
    }

  