anyURIUnion Function Description
Description
This function takes two or more arguments that are both a bag of anyURI values. It returns a bag of anyURI such that it contains all elements of all the argument bags. The function gets rid of duplicates, as determined by the equality functions.
anyURIUnion belongs to the ALFA function reference's
Set functions category. It maps to the XACML function identifier
urn:oasis:names:tc:xacml:1.0:function:anyURI-union, takes 2 or more arguments and returns a value of type A bag of values of type anyURI with no duplicates..
| Property | Value |
|---|---|
| Category | Set functions |
| # Arguments | 2 or more |
| Arguments |
|
| Return Value | A bag of values of type anyURI with no duplicates. |
| Expressed As | pre-fix |
| Representation | ALFA short name |
| Allowed In Target | false |
| ALFA Shorthand | None |
| Commutative | true |
Example
/**
* Deny access if the requested URL is in the list of either spam sites or dangerous sites
*/
rule anyURIUnionExample{
deny
condition anyURIIsIn(anyURIOneAndOnly(requestedURL),anyURIUnion(spamSites, dangerousSites))
}In this example, the anyURIUnion function is used nested inside a anyURIIsIn. It is used to bring together the values from 2 separate attributes (the spam sites and the unsafe sites). Note that this sort of manipulation could also be done by the PIP to make the policy simpler. Note the use of anyURIOneAndOnly on the requested URL as an attribute in ALFA is always deemed multi-valued.
Related Functions
Other functions in the Set functions category: