Re: [jboss-as7-dev] Management proposal for attribute mutability

On 8/22/11 1:26 PM, Brian Stansberry wrote: > On 8/2/11 4:22 PM, Jason T. Greene wrote: >> Currently we have way too many read only attributes in our management >> model. This makes life harder for the management tools and/or makes the >> resulting UI a bit unwieldy. >> >> In some cases this is just because we haven't polished subsystem >> management (PLEASE all subsystem authors look at this!). In other cases >> though it's intentional because it is either difficult or currently >> impossible to make hot changes to a particular attribute. This should be >> exceedingly rare. Users love hot updates, and it's a competitive >> advantage. So first we should strive to make it hot in the first place. >> >> However in the case that the change is not hot, and a server reboot is >> too aggressive, we should still supporting making the changes by >> bouncing all services involved. After some debate on IRC we finally >> arrived at what is IMO a really good option for this problem: >> >> write-attribute (impact-services=true|false) >> >> The operation handler on such a non-hot attribute would then return an >> error > > A handler should not return an error if a change cannot be applied to > the runtime. An OperationStepHandler should use the relevant API on the > OperationContext. E.g. for a handler registered for Stage.RUNTIME: > > @Override > public void execute(OperationContext context, ModelNode operation) { > > context.runtimeUpdateSkipped(); > context.reloadRequired(); // or context.restartRequired(); > if (context.completeStep() == > OperationContext.ResultAction.ROLLBACK) > { > context.revertReloadRequired(); > // or context.revertRestartRequired(); > } > } Well in my above comment I was referring to a problem where a full server reload and/or restart is too aggressive (i.e. why bounce the web server when all you want to do is bounce a datasource). So the issue is that these attributes don't fit that problem.