[wildfly-dev] Batch Subsystem Model

[James R. Perkins]

On 09/12/2013 08:48 PM, David M. Lloyd wrote:
> On 09/12/2013 10:39 PM, James R. Perkins wrote:
>> I'm struggling a bit come up with the right model for the batch
>> subsystem. The XML currently looks like the following, but doesn't have
>> to remain like this if someone has a better idea.
>>
>> <subsystem xmlns="urn:jboss:domain:batch:1.0">
>>        <job-repository value="default"/>
>>
>>        <job-repository-type name="default">
>>            <in-memory thread-pool-name="default"/>
>>        </job-repository>
> End tags
>
>>        <job-repository-type name="jdbc">
>>            <jdbc thread-pool-name="default">
> I don't recall if we use -name suffixes in referential attributes.  I
> don't think we do.
That's what EJB had. You define a thread-pool then on like service=async 
there is a thread-pool-name attribute. I don't really care either way, I 
was just trying to make it consistent.
>
>>                <datasource jndi-name="java:jboss/datasources/ExampleDS"/>
>>            </jdbc>
>>        </job-repository>
>>
>>        <unbounded-queue-thread-pool name="default">
>>            <max-threads count="10"/>
>>            <keepalive-time time="100" unit="milliseconds"/>
>>        </unbounded-queue-thread-pool>
> Rename this element to something like "batch-thread-pool".
No problem. For some reason I was thinking we should allow different 
types to be used, but I guess it doesn't really matter. Really i that 
case it could just be defined within the "job-repository-type".
>
>> </subsystem>
>>
>> This would make the model for the in-memory type something like;
>> "subsystem" => {
>>        "batch" => {
>>            "job-repository" => "default",
>>            "job-repository-type" => {"default" => {
>>                "type" => "in-memory",
>>                "thread-pool-name" => "default"
>>            }}
>>        }
>> }
>>
>> The problem is I'm not sure what to do with JDBC which would also need a
>> datasource/jndi-name attribute, but I don't want that attribute on the
>> in-memory type.
>>
>> Another thought I had was to have it look more like;
>> "subsystem" => {
>>        "batch" => {
>>            "job-repository" => "default",
>>            "in-memory" => {"default" => {
>>                "thread-pool-name" => "default"
>>            }},
>>            "jdbc" => {"jdbc" => {
>>                "thread-pool-name" => "default",
>>                "jndi-name" => "java:jboss/datasources/ExampleDS"
>>            }}
>>        }
>> }
>>
>> The problem here is really the jdbc resource could also be called
>> default. I'm not sure if there is a way to query a parent resource to
>> check each name, but if there is then maybe that's the way to go.
>>
>> Anyway, if anyone has suggestions let me know.
> Why have a separate job-repository from job-repository-type?
>
The only reason was to not use a complex (OBJECT) value for the 
job-repository. In the ideal world I would just have something like

"subsystem" => {
     "batch" => {
         "job-repository" => "in-memory" => {
             "thread-pool" => {
                 "max-threads" => 10,
                 "keepalive" => {
                     "time" => "100",
                     "unit" => "milliseconds"
                 }
             }
         }}
     }
}

Of course for CLI that would be a huge PITA. Maybe it's the best 
solution though. I would simplify the XML as well to something more like;
<subsystem xmlns="urn:jboss:domain:batch:1.0">
     <job-repository>
         <in-memory>
             <thread-pool>
                 <max-threads count="10"/>
                 <keepalive-time time="100" unit="milliseconds"/>
             </thread-pool>
         </in-memory>
     </job-repository>
</subsystem>

The question I would have for that is would it be acceptable to allow 
only specific values (in-memory and jdbc) for the job-repository key?

-- 
James R. Perkins
Red Hat JBoss Middleware