Re: [wildfly-dev] Management Model: Squatter Resources

On Oct 30, 2014, at 9:00 AM, Brian Stansberry <brian.stansberry(a)redhat.com&gt; wrote: I'm not so sure that bad idea was yours. But +1 on getting rid of the existing min/max thing. On 10/30/14, 8:58 AM, David M. Lloyd wrote: > Using schema-ish things like min/max was probably a bad idea on my part. > After trying to model XML schema in various ways for various reasons > over the years, I know now that the simpler our rules are, the easier it > will be to implement a cohesive and useful UX. > > IMO any currently unused and un-useful constructs like this that are > hanging around probably need to be pruned, before someone actually uses > them and makes everyone's live more difficult. :-) > > On 10/30/2014 08:44 AM, Brian Stansberry wrote: >> No, we don't. That currently would have to be handled in a custom way by >> the OSH that does the add for any of the children. >> >> There are some bits and pieces in the metadata that can help with doing >> some sort of automated validation (i.e. a currently basically unused >> max/min child count thing) but I don't think what's there is sufficient. >> >> The fact the metadata isn't there means a client like the console >> couldn't enforce the constraint server side, for a better UX. >> >> On 10/30/14, 8:08 AM, David M. Lloyd wrote: >>> I mean, a single child where there can be many possible types for that >>> child. >>> >>> On 10/30/2014 08:01 AM, David M. Lloyd wrote: >>>> I think that polymorphism is a new use case for 'squatters'. I wonder >>>> if we have any existing code which enforces single children? >>>> >>>> On 10/30/2014 05:40 AM, Jeff Mesnil wrote: >>>>> I’m integrating HornetQ 2.5 in WildFly and I have a new use case for resources that is related to singleton/squatter resources. >>>>> >>>>> In HornetQ 2.5 they have completely rewritten the HA configuration. Basically, a server can be configured as live-only, replicated (master, slave, or colocated) or using shared-store (again as a master, slave or colocated). >>>>> >>>>> To represent this in the management model, I have added several resources under hornetq-server: >>>>> >>>>> /subsystem=messaging/ >>>>> hornetq-server=*/ >>>>> ha-policy=live-only >>>>> ha-policy=replicated-master >>>>> ha-policy=replicated-slave >>>>> ha-policy=replicated-colocated >>>>> ha-policy=shared-store-master >>>>> ha-policy=shared-store-slave >>>>> ha-policy=shared-store-colocated >>>>> >>>>> I have constraints for this ha-policy resource: >>>>> * There can at most one child for this type of resource (no child means no HA). This is enforces during the MODEL stage. >>>>> * The child can only be named using one of the 7 values above (i.e. there is no resource definition for ha-policy=*, using any other name would fail) >>>>> >>>>> Each ha-policy definition has a different set of attributes. Using an attribute group to represent the HA policy does not seem a good fit as some of them have subresources too. >>>>> >>>>> I wonder if that representation fits with our roadmap and whether it can be considered as a singleton (as there can only be one resource of that type among). I have the additional constraints of having only one chile for that type that is not covered by your proposal though. >>>>> >>>>> I especially wonder how the console (and to a lesser extent the cli) can deal with this resource. >>>>> >>>>> Heiko, is it something that would make sense for the console based on this resource description: >>>>> >>>>> [standalone@localhost:9990 hornetq-server=default] ./ha-policy=*:read-resource-description(recursive-depth=1) >>>>> { >>>>> "outcome" => "success", >>>>> "result" => [ >>>>> { >>>>> "address" => [ >>>>> ("subsystem" => "messaging"), >>>>> ("hornetq-server" => "default"), >>>>> ("ha-policy" => "replication-colocated") >>>>> ], >>>>> "outcome" => "success", >>>>> "result" => { >>>>> ... >>>>> } >>>>> }, >>>>> { >>>>> "address" => [ >>>>> ("subsystem" => "messaging"), >>>>> ("hornetq-server" => "default"), >>>>> ("ha-policy" => "replication-master") >>>>> ], >>>>> "outcome" => "success", >>>>> "result" => { >>>>> ... >>>>> } >>>>> }, >>>>> { >>>>> "address" => [ >>>>> ("subsystem" => "messaging"), >>>>> ("hornetq-server" => "default"), >>>>> ("ha-policy" => "shared-store-slave") >>>>> ], >>>>> "outcome" => "success", >>>>> "result" => { >>>>> ... >>>>> } >>>>> }, >>>>> { >>>>> "address" => [ >>>>> ("subsystem" => "messaging"), >>>>> ("hornetq-server" => "default"), >>>>> ("ha-policy" => "live-only") >>>>> ], >>>>> "outcome" => "success", >>>>> "result" => { >>>>> ... >>>>> } >>>>> }, >>>>> { >>>>> "address" => [ >>>>> ("subsystem" => "messaging"), >>>>> ("hornetq-server" => "default"), >>>>> ("ha-policy" => "shared-store-master") >>>>> ], >>>>> "outcome" => "success", >>>>> "result" => { >>>>> ... >>>>> } >>>>> }, >>>>> { >>>>> "address" => [ >>>>> ("subsystem" => "messaging"), >>>>> ("hornetq-server" => "default"), >>>>> ("ha-policy" => "replication-slave") >>>>> ], >>>>> "outcome" => "success", >>>>> "result" => { >>>>> ... >>>>> } >>>>> }, >>>>> { >>>>> "address" => [ >>>>> ("subsystem" => "messaging"), >>>>> ("hornetq-server" => "default"), >>>>> ("ha-policy" => "shared-store-colocated") >>>>> ], >>>>> "outcome" => "success", >>>>> "result" => { >>>>> ... >>>>> } >>>>> } >>>>> ] >>>>> } >>>>> >>>>> jeff >>>>> >>>> >>> >> >> > -- Brian Stansberry Senior Principal Software Engineer JBoss by Red Hat _______________________________________________ wildfly-dev mailing list wildfly-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/wildfly-dev