Documenting Predicates, Functions (and ActivationConditions)

[Rod Widdowson]

We discusses this on Friday; it's all part of IDP-1314, but I'd like a slightly wider audience than just the comments section of
that case.

I have a desire, provoked (as was IDP-1314) from a Support case asking for a MetadataFilter on the RegExp of the EntityID, to
provide documentation for all the Functions and Predicates that are declared system\conf\utilities.xml.

As I started on this yesterday I (re) discovered the ActivationConditions[1] page, this is an awesome cookbook for on particular
flavour of what I want to get documented (Specifically Predicate<ProfileRequestContext>).

I rather badly do not want to disturb that page too much (it should be a bookmark for anyone doing complex deployments).  So my plan
(which I want to test with this audience) is to:

- Collapse ExternalAttributePluginActivationConditions [2] into ActivationConditions[1] (partially completed yesterday)

- Build a page under SpringConfiguration [3] documenting Functions and Predicates (probably move the words in preface to
ActivationConditions) making sure it is understood that this is the list of potential ingredients and, not the cook-book

- Under this, detail (probably in a table, but maybe a page per bean) each Predicate/Function featuring
   - Abstract Bean name (from utilities.xml)
   - Signature (Function/Predicate and input/output types)
   - Reference to the JavaDoc
   - An example
   - I also would like list the Constructor names, Factory names, property names.  This does duplicate the Javadoc but does keep
everything together..

This leave ActivationsConditions as a crib sheet for them and we have single goto list for all Functions and Predicates.  Obviously
each page would reference the other

Obviously the details plan will change as I actually do the writing, but I wanted to garner input before I start..

Rod

[1] https://wiki.shibboleth.net/confluence/display/IDP30/ActivationConditions
[2] https://wiki.shibboleth.net/confluence/display/IDP30/ExternalAttributePluginActivationConditions
[3] https://wiki.shibboleth.net/confluence/display/IDP30/SpringConfiguration