SizeConstraintStatement - Amazon WAFV2
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A rule statement that compares a number of bytes against the size of a request component, using a comparison operator, such as greater than (>) or less than (<). For example, you can use a size constraint statement to look for query strings that are longer than 100 bytes.

If you configure Amazon WAF to inspect the request body, Amazon WAF inspects only the number of bytes in the body up to the limit for the web ACL and protected resource type. If you know that the request body for your web requests should never exceed the inspection limit, you can use a size constraint statement to block requests that have a larger request body size. For more information about the inspection limits, see Body and JsonBody settings for the FieldToMatch data type.

If you choose URI for the value of Part of the request to filter on, the slash (/) in the URI counts as one character. For example, the URI /logo.jpg is nine characters long.



The operator to use to compare the request part to the size setting.

Type: String

Valid Values: EQ | NE | LE | LT | GE | GT

Required: Yes


The part of the web request that you want Amazon WAF to inspect.

Type: FieldToMatch object

Required: Yes


The size, in byte, to compare to the request part, after any transformations.

Type: Long

Valid Range: Minimum value of 0. Maximum value of 21474836480.

Required: Yes


Text transformations eliminate some of the unusual formatting that attackers use in web requests in an effort to bypass detection. Text transformations are used in rule match statements, to transform the FieldToMatch request component before inspecting it, and they're used in rate-based rule statements, to transform request components before using them as custom aggregation keys. If you specify one or more transformations to apply, Amazon WAF performs all transformations on the specified content, starting from the lowest priority setting, and then uses the transformed component contents.

Type: Array of TextTransformation objects

Array Members: Minimum number of 1 item.

Required: Yes

See Also

For more information about using this API in one of the language-specific Amazon SDKs, see the following: