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

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 >> >