Attribute Resolution

Attribute resolution strategies are controlled by the Person Directory project. The Person Directory dependency is automatically bundled with the CAS server. Therefore, declaring an additional dependency will not be required. This Person Directory project supports both LDAP and JDBC attribute resolution, caching, attribute aggregation from multiple attribute sources, etc.

Default Caching Policy

By default, attributes are cached to the length of the SSO session. This means that while the underlying component provided by Person Directory may have a different caching model, attributes by default and from a CAS perspective will not be refreshed and retrieved again on subsequent requests as long as the SSO session exists.

Administrative Endpoints

The following endpoints are provided by CAS:

Endpoint Description
resolveAttributes/{name} Invoke the CAS attribute resolution engine to locate attributes for {name}.

Person Directory

A framework for resolving persons and attributes from a variety of underlying sources. It consists of a collection of components that retrieve, cache, resolve, aggregate, merge person attributes from JDBC, LDAP and more.

Attribute sources are defined and configured to describe the global set of attributes to be fetched for each authenticated principal. That global set of attributes is then filtered by the service manager according to service-specific attribute release rules.

Note that each attribute repository source can be assigned a unique identifier to be used for additional filtering. The attribute resolution engine provided by Person Directory can also be configured to only consult not all but a selection of attribute repository sources, deferring the task of attribute retrieval for later phases in the authentication process, such as releasing attributes.

Principal Resolution

Note that in most if not all cases, CAS authentication is able to retrieve and resolve attributes from the authentication source, which would eliminate the need for configuring a separate resolver specially if both the authentication and the attribute source are the same. Using separate resolvers should only be required when sources are different, or when there is a need to tackle more advanced attribute resolution use cases such as cascading, merging, etc. See this guide for more info.

The goal of the resolver is to construct a final identifiable authenticated principal for CAS which carries a number of attributes inside it. The behavior of the person-directory resolver is such that it attempts to locate the principal id, which in most cases is the same thing as the credential id provided during authentication or it could be noted by a custom attribute. Then the resolver starts to construct attributes from attribute repositories defined. If it realizes that a custom attribute is used to determine the principal id AND the same attribute is also set to be collected into the final set of attributes, it will then remove that attribute from the final collection.

Note that by default, CAS auto-creates attribute repository sources that are appropriate for LDAP, JDBC, etc. If you need something more, you will need to resort to more elaborate measures of defining the bean configuration.

More about the Person Directory and its configurable sources can be found here.

Overview

Control the set of authentication attributes that are retrieved by the principal resolution process, from attribute sources unless noted otherwise by the specific authentication scheme.

If multiple attribute repository sources are defined, they are added into a list and their results are cached and merged.

The following settings and properties are available from the CAS configuration catalog:

The configuration settings listed below are tagged as Required in the CAS configuration metadata. This flag indicates that the presence of the setting is not strictly necessary in the end-user CAS configuration, because a default value may be assigned or the feature in question may not be immediately intended for use. You may want to own the setting and update it assigned value, assuming the intended feature controlled by the setting is utilized.