[rules-users] No errors thrown from KnowledgeAgent

De Rooms Brecht bderooms at vub.ac.be
Tue Sep 17 16:51:15 EDT 2013 

Dear Drools users,

Apparently it was not caused by the previously mentioned fix. Sometimes 
I still had a KnowledgeAgent in my server that doesn't respond anymore 
which seems to be caused by a mistake in the DRL file.
I started to investigate the source code of KnowledgeAgentImpl and 
KnowledgeBaseImpl and recompiled them to add some prints. Finally I 
tracked it until AbstractRuleBase.addPackages.

There is a giant Try-final block and I noticed by adding prints that it 
stopped somewhere in the middle. When it does fail, my KnowledgeAgent 
stops working completely.
The try-final seemed to be the only place for me where an exception 
might be ignored so I added a catch clause.
As a result, the error report of my drl file was nicely printed and my 
agent didn't crash:

*org.drools.RuntimeDroolsException: Unable to resolve class 'int' for 
global 'RULES_MATCHED'
     at 
org.drools.common.AbstractRuleBase.mergePackage(AbstractRuleBase.java:818)
     at 
org.drools.common.AbstractRuleBase.addPackages(AbstractRuleBase.java:615)
     at 
org.drools.reteoo.ReteooRuleBase.addPackages(ReteooRuleBase.java:472)
     at 
org.drools.impl.KnowledgeBaseImpl.addKnowledgePackages(KnowledgeBaseImpl.java:153)
     at 
org.drools.agent.impl.KnowledgeAgentImpl.addResourcesToKnowledgeBase(KnowledgeAgentImpl.java:1173)
     at 
org.drools.agent.impl.KnowledgeAgentImpl.incrementalBuildResources(KnowledgeAgentImpl.java:1058)
     at 
org.drools.agent.impl.KnowledgeAgentImpl.buildKnowledgeBase(KnowledgeAgentImpl.java:738)
     at 
org.drools.agent.impl.KnowledgeAgentImpl.applyChangeSet(KnowledgeAgentImpl.java:259)
     at 
org.drools.agent.impl.KnowledgeAgentImpl$ChangeSetNotificationDetector.run(KnowledgeAgentImpl.java:1357)
     at 
java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
     at java.util.concurrent.FutureTask.run(FutureTask.java:166)
     at 
java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
     at java.util.concurrent.FutureTask.run(FutureTask.java:166)
     at 
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
     at 
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
     at java.lang.Thread.run(Thread.java:722)
*
Maybe there is a reason for this missing catch so I am not sure whether 
I fixed it and broke something else ( eg. maybe I should undo a part of 
the operations before I continue).
Is there anyone who knows this code and who can help me?

Extra information:
     - I use Drools 5.5 from the Maven repository.
     - my agent configuration:
                 agentConf.setProperty("drools.agent.newInstance", "false");
agentConf.setProperty("drools.agent.useKBaseClassLoaderForCompiling", 
"true");


Kind Regards,
De Rooms Brecht

Op 31/07/2013 14:45, De Rooms Brecht schreef:
> The bug was caused by one of the InputStreams that was not closed 
> properly which caused the knowledgeAgent to block.
> I think my issues are solved now.
>
> Thanks for looking into this.
> Kind Regards,
>
> Op 31/07/2013 14:19, De Rooms Brecht schreef:
>> Hello David and thanks for responding.
>> I know it supports these event listeners and I use them. In my 
>> program, I have two knowledge agents and the first one 
>> (preprocessing) will read the file, preprocess a DRL and then write a 
>> second modified DRL file in a folder that is monitored by the second 
>> one. When I modify the original DRL file *(1.* in prints below*)* 
>> monitored by the preprocessing agent, everything works fine and the 
>> rule is triggered*(**2.)*. However, when I delete a file *(**3.)*, 
>> the knowledgeAgent just blocks after AfterChangeSetAppliedEvent and 
>> does not do anything anymore.. If I send new data in the 
>> knowledgeAgent it does not react anymore.
>>
>> I would expect to get a stacktrace of what went wrong but I do not 
>> get any info besides of the systemeventlistener or 
>> knowledgeagentlistener. Is there any way I can get a stacktrace?
>> Kind Regards,
>> De Rooms Brecht
>>
>> _*1. Resources Changed => Modified:  [[FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']]*_
>> /    eventListener 1::: 
>> ==>[BeforeResourceProcessedEvent(RESOURCE_REMOVED): [FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']]//
>> //    eventListener 1::: 
>> ==>[AfterResourceProcessedEvent(RESOURCE_REMOVED): [FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']]//
>> //    eventListener 1::: ==>[AfterChangeSetProcessedEvent: 
>> ChangeSetImpl{resourcesRemoved=[], resourcesAdded=[], 
>> resourcesModified=[[FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']], 
>> knowledgeDefinitionsRemoved=[]}]//
>> //    eventListener 1::: ==>[ResourceCompilationFailedEvent: 
>> org.drools.builder.impl.KnowledgeBuilderImpl at 70d0d127]//
>> //    eventListener 1::: ==>[KnowledgeBaseUpdatedEvent: 
>> org.drools.impl.KnowledgeBaseImpl at 49669be]//
>> //    eventListener 1::: ==>[AfterChangeSetAppliedEvent: 
>> ChangeSetImpl{resourcesRemoved=[], resourcesAdded=[], 
>> resourcesModified=[[FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']], 
>> knowledgeDefinitionsRemoved=[]}]//
>> //    eventListener 2::: ==>[BeforeChangeSetAppliedEvent: 
>> ChangeSetImpl{resourcesRemoved=[], resourcesAdded=[], 
>> resourcesModified=[[FileResource 
>> file='knowledge\packaged\test.brules.testRule.drl']], 
>> knowledgeDefinitionsRemoved=[]}]//
>> //    eventListener 2::: 
>> ==>[BeforeResourceProcessedEvent(RESOURCE_REMOVED): [FileResource 
>> file='knowledge\packaged\test.brules.testRule.drl']]//
>> //    eventListener 2::: 
>> ==>[AfterResourceProcessedEvent(RESOURCE_REMOVED): [FileResource 
>> file='knowledge\packaged\test.brules.testRule.drl']]//
>> //    eventListener 2::: ==>[AfterChangeSetProcessedEvent: 
>> ChangeSetImpl{resourcesRemoved=[], resourcesAdded=[], 
>> resourcesModified=[[FileResource 
>> file='knowledge\packaged\test.brules.testRule.drl']], 
>> knowledgeDefinitionsRemoved=[]}]//
>> //    eventListener 2::: ==>[KnowledgeBaseUpdatedEvent: 
>> org.drools.impl.KnowledgeBaseImpl at 11c834d1]/
>>
>> _*2. Rules are triggered when the PKG file its knowledge is updated:*_
>> /    Changed This Rule::: Got Event: TestEvent( number=5, 
>> message=doesDynamicEventTypeWork? )//
>> //    Changed This Rule::: Got Event: TestEvent( number=4, 
>> message=doesDynamicEventTypeWork? )//
>> //    Changed This Rule::: Got Event: TestEvent( number=2, 
>> message=doesDynamicEventTypeWork? )//
>> //    Changed This Rule::: Got Event: TestEvent( number=1, 
>> message=doesDynamicEventTypeWork? )//
>> //    Changed This Rule::: Got Event: TestEvent( number=2, 
>> message=doesDynamicEventTypeWork? )//
>> //    Changed This Rule::: Got Event: TestEvent( number=1, 
>> message=doesDynamicEventTypeWork? )//
>> //    Changed This Rule::: Got Event: TestEvent( number=2, 
>> message=doesDynamicEventTypeWork? )//
>> //    Changed This Rule::: Got Event: TestEvent( number=1, 
>> message=doesDynamicEventTypeWork? )//
>> //
>> //    eventListener 2::: ==>[AfterChangeSetAppliedEvent: 
>> ChangeSetImpl{resourcesRemoved=[], resourcesAdded=[], 
>> resourcesModified=[[FileResource 
>> file='knowledge\packaged\test.brules.testRule.drl']],     
>> knowledgeDefinitionsRemoved=[]}]//
>> //    eventListener 1::: ==>[BeforeChangeSetAppliedEvent: 
>> ChangeSetImpl{resourcesRemoved=[[FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']], 
>> resourcesAdded=[],                 resourcesModified=[], 
>> knowledgeDefinitionsRemoved=[]}]//
>> //    eventListener 1::: ==>[BeforeChangeSetProcessedEvent: 
>> ChangeSetImpl{resourcesRemoved=[[FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']], 
>> resourcesAdded=[], resourcesModified=[], 
>> knowledgeDefinitionsRemoved=[]}]/
>>
>>
>> _*3. *__*Resources Changed => *__*Removed:   [[FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']]*_
>> /    eventListener 1::: 
>> ==>[BeforeResourceProcessedEvent(RESOURCE_MODIFIED): [FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']]//
>> //    eventListener 1::: 
>> ==>[AfterResourceProcessedEvent(RESOURCE_MODIFIED): [FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']]//
>> //    eventListener 1::: ==>[AfterChangeSetProcessedEvent: 
>> ChangeSetImpl{resourcesRemoved=[[FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']], 
>> resourcesAdded=[], resourcesModified=[], 
>> knowledgeDefinitionsRemoved=[]}]//
>> //    eventListener 1::: ==>[KnowledgeBaseUpdatedEvent: 
>> org.drools.impl.KnowledgeBaseImpl at 49669be]//
>> //    eventListener 1::: ==>[AfterChangeSetAppliedEvent: 
>> ChangeSetImpl{resourcesRemoved=[[FileResource 
>> file='knowledge\realtimeKnowledge\test.brules.testRule.drl']], 
>> resourcesAdded=[], resourcesModified=[], 
>> knowledgeDefinitionsRemoved=[]}]/
>>
>>  .... and then it was quiet....
>>
>> Op 31/07/2013 09:42, Davide Sottara schreef:
>>> The KA logs to a SystemEventListener, and supports a dedicated event
>>> listener for
>>> additions/updates/etc...
>>>
>>> You can do:
>>>
>>> kagent.setSystemEventListener( new PrintStreamSystemEventListener() );
>>> kagent.addEventListener( new DebugKnowledgeAgentEventListener(  ) );
>>>
>>>
>>>
>>> On 07/30/2013 01:55 AM, De Rooms Brecht wrote:
>>>> Dear Drools users,
>>>>
>>>> I have been testing with the KnowledgeAgent from version 5.4 and 5.5. It
>>>> monitors a changeset and is set to incrementally build the
>>>> knowledgebase. I noticed that it sometimes crashes but never throws out
>>>> errors. This happens for example when I define a type two times and when
>>>> I remove a file. Does anyone experience similar behaviour and has an
>>>> idea of how I could see the errors? I already tried to check the errors
>>>> by building it myself using a knowledgebuilder before I update the file
>>>> that the knowledgeAgent monitors but that's quite a dirty solution.
>>>>
>>>> Kind Regards,
>>>> De Rooms Brecht
>>>> _______________________________________________
>>>> 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
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>>>
>>
>>
>>
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>
>
>
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