[jboss-as7-dev] Subsystem specific deployer configurations in standalone.xml/domain.xml

[Brian Stansberry]

I want to see what comes out of 
https://github.com/jbossas/jboss-as/pull/3397

On 11/14/12 4:41 AM, Thomas Diesler wrote:
> Hi Brian,
>
> wanted touch base with you on this - any news?
>
> cheers
> --thomas
>
> On 10/15/2012 11:45 PM, Brian Stansberry wrote:
>> I've been working $subject in order to help support Thomas Diesler's
>> request for AS7-3694[1]. The gist of this request is to add deployment
>> unit processing (DUP) configuration as children of the deployment
>> resource itself. Thomas' OSGi use case is one place where this would be
>> used. I expect HASingleton deployment will be another.
>>
>> WIP is at [2]. I'm looking for feedback. :)
>>
>> What I've done is based on what Thomas did at [3]. What I want to do is
>> move from the generic key/value pairs in that patch to a more formally
>> describable management API. Instead of:
>>
>> <deployment name="foo.war"...>
>>    <properties>
>>     <property name="start.policy" value="DEFERRED"/>
>>    <property>
>> </deployment>
>>
>> It would be something analogous to how a profile configuration is done:
>>
>> <deployment name="foo.war"...>
>>    <deployment-subsystem xmlns="urn:jboss:domain:osgi:1.2">
>>      <start-policy value="deferred"/>
>>    </deployment>
>> </deployment>
>>
>> The existing Extension API already has the hooks to support this.
>> Extensions can register xml parsers for children of the <deployment>
>> element and can register management resources to act as children of the
>> /deployment=foo.war resource as well. Several subsystems already take
>> advantage of the latter. Until now the former has been an unimplemented
>> API. The commit at [4] implements it.
>>
>> A couple things giving me some concern:
>>
>> 1) The above xml:
>>
>> <deployment-subsystem xmlns="urn:jboss:domain:osgi:1.2">
>>
>> Nicer would be something like:
>>
>> <deployers>
>>     <subsystem xmlns="urn:jboss:domain:osgi:1.2">
>>
>> I need to figure out if I can do some tricks with the parsing to allow
>> that to happen.
>>
>> 2) The structure of the resource tree. We already support resources like
>> this:
>>
>> /deployment=foo.war/subsystem=web
>>
>> Subsystems register resources like those to expose metrics. The commit
>> at [4] uses that same tree. When subsystems could now register child
>> resources to the deployment=* resource, they could include both runtime
>> stuff and configuration stuff.
>>
>> I'm not sure that mixing the two is ideal, although it's what we do for
>> the regular subsystem resources in the profile. I'm vaguely concerned
>> that if someday the configuration that subsystems choose to expose via
>> this mechanism gets complex, the mixing of metrics with configuration in
>> the same tree will start to break down.
>>
>> Comments are appreciated.
>>
>>
>> [1] https://issues.jboss.org/browse/AS7-3694
>> [2] https://github.com/bstansberry/jboss-as/commits/AS7-3694
>> [3] https://github.com/jbossas/jboss-as/pull/3230
>> [4]
>> https://github.com/bstansberry/jboss-as/commit/6326003a104ac4ac825e8dda4c557cfefe9cdcfd
>>
>


-- 
Brian Stansberry
Principal Software Engineer
JBoss by Red Hat