Attribute Release Policy - Inline Groovy
Principal attributes that are mapped may produce their values from an inline groovy script.
Activating this policy is not without cost, as CAS needs to evaluate the inline script, compile and run it for subsequent executions. While the compiled script is cached and should help with execution performance, as a general rule, you should avoid opting for and designing complicated scripts.
-
As an example, if you currently have resolved a
uidattribute with a value ofpiper, you could then consider the following:1 2 3 4 5 6 7 8 9 10 11 12 13
{ "@class" : "org.apereo.cas.services.CasRegisteredService", "serviceId" : "sample", "name" : "sample", "id" : 300, "attributeReleasePolicy" : { "@class" : "org.apereo.cas.services.ReturnMappedAttributeReleasePolicy", "allowedAttributes" : { "@class" : "java.util.TreeMap", "uid" : "groovy { return attributes['uid'].get(0) + ' is great' }" } } }
In the above snippet, the value of the
uidattribute name is mapped to the result of the inline groovy script. Inline scripts always begin with the syntaxgroovy {...}and are passed the current collection of resolved attributes as anattributesbinding variable. The result of the script can be a single/collection of value(s).The above configuration will produce a
uidattribute for the application whose value is a concatenation of the original value ofuidplus the wordsis great. The final result would bepiper is great.To prepare CAS to support and integrate with Apache Groovy, please review this guide.
-
This is a more complicated example of an inline Groovy script that calculates the value for the
memberOfattribute. You will notice the Groovy script is defined as a multiline string that is directly mapped to the attribute.Given a
memberOfattribute value ofCN=Colleague Admins,OU=Computer Services Users, thememberOfattribute that is calculated by the below attribute release policy will produceColleague Adminsas its value.1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
{ "@class": "org.apereo.cas.services.CasRegisteredService", "serviceId": "^https://app.example.org/.+", "id": 1, "name": "Sample", "attributeReleasePolicy" : { "@class" : "org.apereo.cas.services.ReturnMappedAttributeReleasePolicy", "allowedAttributes" : { "@class" : "java.util.TreeMap", "memberOf" : ''' groovy { def value = attributes['memberOf']?.get(0) as String println "memberOf attribute: $value" if (value != null) { def matcher = (value =~ ~/(CN=)(.*?)(?<!\\),.*/) if (matcher.find()) { def match = matcher.group(2) println "Found a match: $match" return match } println "No match found for memberOf. Returning $value" return value } println "No memberOf attribute is found" return null } ''' } } }
You may also be interested in doing almost the same thing via Pattern Matching.
Usage WarningAs you may note, this can get ugly very quickly especially if you decide to be super creative with the scripting logic and/or decide to duplicate the same kind of script throughout other service policy files. Inline Groovy scripts are meant to be brief and efficient and you are encouraged to not get too complicated with the structure of the script and the behavior it delivers.
To prepare CAS to support and integrate with Apache Groovy, please review this guide.