Extending the SP Dynamic Metadata Provider

[Rod Widdowson]

> I guess that makes sense, though I wonder if we want to just define an alternate plugin type/synonym for this and bake in a simpler set of
> assumptions altogether. Then the URL can be an attribute inside the MetadataProvider element and be done with it.

It probably makes the documentation easier.  I'd need to work out how to do it in the code.  I suppose you just register another factory and have that call the same constructor - the Folder MetadataProvider will be the paradigm to follow?
 
> > This would allow us to deprecate (but not disallow) file:// URLs.
> 
> I don't know that I want to maintain a second way to do this when it really hasn't been used much anyway, and there's a nasty pass
> through to curl involved here that probably isn't a great thing to keep. I did it because it was a free side effect but if we make it a real
> feature, I think we should wrap all of it.

Fair enough

> > As far as configuration goes, that’s all I can see by way of low hanging fruit.  Have I missed something?  Or have I got something
> > wrong?
> 
> The only thing I know of offhand, without a lot of familiarity with the IdP version, is the preload option, to pull in uncached copies of
> particular IdP metadata at startup.

I don’t see that in the documentation.  I'll poke at the code, or maybe Brent can chime in.  On the other hand, isn't reloading from the local cache not going to do much of what you want except when you are bootstrapping a new system.

As I researched this I realized that I had misinterpreted the local cache in the IdP.  It preloads the in memory cache with the contents of the disk cache.  This is can also be done in a worker thread, potentially deferred (hence more configuration).  The IdP uses "initializeFromPersistentCacheInBackground" and "backgroundInitializationFromCacheDelay".   Do these attribute names work ?  If so we'd probably want to us "persistentCacheDirectory" (dropping the IdP's "Manager" from the name since there is no pluggable manager for the SP.

Rod