Metadata can be filtered, after loading it but before its use. Filters are specified as a series of <MetadataFilter>
elements, which are processed in the order in which they occur as children of the containing <MetadataProvider>
element.
Like metadata providers, metadata filters are defined by their xsi:type
attribute. All other attributes and child elements are specific to each filter. The filter types provided are:
- Chaining Filter (DEPRECATED)
- Normally automatically applied whenever multiple filters appear, this wraps multiple filters into a chain, running each one in turn
- RequiredValidUntil Filter
- Important for secure processing of metadata containing keys, this filter forces the metadata to carry an expiration date and limits the size of the corresponding validity interval
- SchemaValidation Filter
- Performs XML schema validation on the metadata
- SignatureValidation Filter
- A common filter that checks the signature on signed metadata
- EntityRoleWhiteList Filter
- A memory-saving filter that deletes unneeded role information from the metadata
- EntityAttributes Filter
- A policy aid, this filter actually adds information, allowing "tags" to be attached to metadata for use in other parts of the system
- Predicate Metadata Filter
- An extensible allow/deny filter that removes matching (or keeps only matching) entities based on a set of built-in rules, or with an arbitrary condition
- NameIDFormat Filter 3.3
- A policy aid, this filter adds information, allowing
<NameIDFormat>
elements to be attached to metadata for use in driving identifier format selection.