idp auth module plugin

[Paul Henson]

So I've been plugging along (hee hee) and after some interesting 
adventures in figuring out which net.shibboleth references to change to 
id.signet since this isn't currently an official module and which ones 
needed to stay net.shibboleth to be properly referenced and loaded by 
the idp I've got my basic plug-in structure built and installed and its 
flow successfully called from the MFA config. All it does at this point 
is to just say "hi, I'm here" and succeed, but I think most of the black 
magic is out of the way and getting the functionality going will 
hopefully be straightforward.

I had a question regarding the plug-in installation process; my initial 
module.properties configuration included:

idp.authn.rapid.1.src = 
/id/signet/idp/plugin/authn/rapid/conf/authn/rapid.properties
idp.authn.rapid.1.dest = conf/authn/rapid.properties
idp.authn.rapid.1.optional = true


The first time I installed the module, it created the rapid.properties 
file. Then when I removed it, it deleted it. However, from then on 
whenever I reinstalled the module it would not create the file again. 
Removing the module it just noted that the file wasn't there to remove.

I changed optional to "false", and then installing the module added the 
file again. My understanding of the optional flag is whether or not a 
module upgrade or reinstallation should forcibly overwrite an existing 
file of that name, or leave it alone if it is already there. I'm not 
quite sure though why the unmodified file is removed, but then never 
reinstalled when it is optional?