Re: [jboss-as7-dev] Do new model attributes require manual setup of transformers?

On 5 Mar 2013, at 14:23, Jaikiran Pai wrote: > I've been trying to implement a new feature which requires the addition > of a new model attribute for the EJB3 subsystem root resource. This > model attribute is supposed to be "mandatory" (i.e. non-nullable at > model level and "required" at xml level). All works fine without > bringing into picture older versions of the model. Now while testing > with older versions of the model and compatibility, things start failing > for obvious reasons- the older model handlers, parsers etc... have no > clue about this new attribute. I'm aware that that's where the The old parsers should make it possible to construct the current model. Is the new attribute something which is now configurable, so you have two choices whereas previously one of those choices was assumed? In that case I think the old parser should create the resulting operation with the assumed default.

> subsystems and resources introducing a new attribute in the > higher model would expect that that attribute to be ignored (I'm not > using the term discarded or rejected because I am not 100% sure I > understand the difference yet :) ) by lower versions of the model. discard = silently discard the attribute reject = if the attribute is used/does not have some value/is defined/other conditions the transformation should fail Normally we prefer reject. So for your case, again assuming that the added attribute has some assumed value in the old version, you should fail transformation if the current model does not have that assumed value.