[jboss-as7-dev] Optional modules / subsystems usage best practices?

[Marek Goldmann]

Hi all,

We are able to make a dependency optional in modules.xml. That's 
awesome, now the question is how to use this feature in real life? Are 
there any best practices?

A bit of background.

In TorqueBox we add several subsystems to the plain JBoss AS 7. We plan 
to have a slimmed down TB called TorqueBox Lite, that will run as a 
RubyGem directly. It's obvious that we would like to slim down the JBoss 
AS distribution itself too since >120MB is too big for a reasonable 
sized Gem. I dropped everything we don't need and I end up with JBoss AS 
distribution that weights ~15MB.

In the TB Lite version we don't need several of AS7 subsystems, that are 
required in the normal TB distribution. One example is the jmx 
subsystem. It's currently marked as optional in the TB core subsystem.

How can I make sure I use the jmx subsystem only when it's available? It 
would be ideally if we could disable some subsystems without breaking 
the platform and instead just remove some features. What's the best way 
to do it?

Thanks!

--Marek