[rules-users] Drools & JBPM Persistence

[Mauricio Salatino]

I think that you are mixing things up.
Did you take a look at the CommandBasedStatefulKnowledgeSession?
Every command that represent an operation against the knowledge session is
being executed inside a transaction, for both rules and processes. As soon
as a safe point is found (for both processes and rules) the persistence
mechanism commits the transaction.

"In fact, this will never dissapear unless some communication mechanism
between Drools & JBPM is developed to allow the processes to be executed
inside Drools Reteoo thread."
Take a look at the class that I mention and then try to explain me what you
mean with the previous sentence.

Cheers

On Fri, Jun 22, 2012 at 9:45 AM, Alberto R. Galdo <argaldo at gmail.com> wrote:

>
> No, I didn't. I need to be able to deploy the human task server and my
> knowledge session in separate JVM's. And Mina is on my way.
>
> The fact that I am able to do things in some other way doesn't make this
> very problem dissapear ... :(. In fact, this will never dissapear unless
> some communication mechanism between Drools & JBPM is developed to allow
> the processes to be executed  inside Drools Reteoo thread.
>
> Isn't that so?
>
>
> Alberto R. Galdo
> argaldo at gmail.com
>
>
>
> On Fri, Jun 22, 2012 at 2:17 PM, Mauricio Salatino <salaboy at gmail.com>wrote:
>
>> Both persistence mechanisms are already unified.
>> the jBPM-persistence module extends the Drools one adding the relevant
>> entities by the processes.
>>
>> You can be having problems with the Mina Server, did you try the local
>> configuration? The Mina Server was designed to run in a different JVM than
>> the session, as a standalone component, if you are running it in the same
>> JVM that can be causing some transactional problems as you mention. If you
>> need to run it in the same JVM you can use the local configuration, did you
>> try that?
>> Cheers
>>
>> On Fri, Jun 22, 2012 at 8:31 AM, Alberto R. Galdo <argaldo at gmail.com>wrote:
>>
>>> Hi,
>>>
>>>    I'm opening this thread in the aim of generating a debate about the
>>> approach to session persistence in Drools and JBPM for BPMN processes which
>>> by definition are able to generate asynchronous human tasks.
>>>
>>>    IMHO the current approach needs to be refactored in favor of joining
>>> the management of the different Drools and JBPM entities in an unique
>>> manager.
>>>
>>>    The current implementation offers two managers one in Drools, one in
>>> JBPM. Each of this managers are wrappers of a shared JPA EntityManager
>>> context and manage their own entities.
>>>
>>>    When the integration of JBPM into Drools was done ( leaving behind
>>> drools flow ), the approach seemed to be to make the entities in JBPM (
>>> workitems, processinstance and so on ) look like the entities in Drools. As
>>> a result, the implementation of those entities in JBPM now implement the
>>> interfaces of the same entities in Drools. That looked like a good
>>> approach, but the experience, at least mine, seems to reveal it as not that
>>> good.
>>>
>>>    In my opinion, the first problem with that approach is that Drools,
>>> the reteoo algorithm, runs in a single-threaded environment. Drools
>>> persistence was designed having this in mind, so for the code in Drools,
>>> there's no doubt that when in a persistent enviroment, the transaction, if
>>> any, will be bound to the same thread as the one in which the reteoo
>>> algorithm is executed. That leads to situations where whenever a class in
>>> JBPM calls drools in a JBPM's thread ( the mina handler thread, a NIO one
>>> for instance ), Drools thinks that is being executed in it's own thread (
>>> where things are expected, as the JTA transaction bound for example ) and
>>> clearly, in some situations it is not the case. Then Drools expects to find
>>> certain resources and certain environment which are not always there.
>>> Leading to failure.
>>>
>>>    As Drools now is a dependency for JBPM through the Knowledge-API, I
>>> think that the management of the persistence for Drools and JBPM should be
>>> merged in one that makes no assumptions and manages the needs for
>>> persistence in a coherent way for both products.
>>>
>>>    What do you think?
>>>
>>>
>>> "There can be only one" ->
>>> http://en.wikipedia.org/wiki/Highlander_%28film%29
>>>
>>>
>>> Alberto R. Galdo
>>> argaldo at gmail.com
>>>
>>>
>>> _______________________________________________
>>> rules-users mailing list
>>> rules-users at lists.jboss.org
>>> https://lists.jboss.org/mailman/listinfo/rules-users
>>>
>>>
>>
>>
>> --
>>  - MyJourney @ http://salaboy.wordpress.com
>>  - Co-Founder @ http://www.jugargentina.org
>>  - Co-Founder @ http://www.jbug.com.ar
>>
>>  - Salatino "Salaboy" Mauricio -
>>
>>
>> _______________________________________________
>> rules-users mailing list
>> rules-users at lists.jboss.org
>> https://lists.jboss.org/mailman/listinfo/rules-users
>>
>>
>
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>
>


-- 
 - MyJourney @ http://salaboy.wordpress.com
 - Co-Founder @ http://www.jugargentina.org
 - Co-Founder @ http://www.jbug.com.ar

 - Salatino "Salaboy" Mauricio -
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20120622/49f31ae2/attachment-0001.html