Re: [rules-users] Strange intermittent problem with Drools Flow

Hi Mauricio, Thanks for looking into this. These are the types of errors that scare me.  They only happen in one environment and I cannot reproduce them. How will I know if it happens in production? We generate our rule flow's dynamically from our own concept of a process flow.  I don't have a custom work item implementation, but I do have a custom WorkItemHandler registered against work items of type "Step" called StepWorkItemHandler. StepWorkItemHandler has uses and injected CallbackHandler to do actual processing.  In test code, the injected callback handler just records what steps (work items) have been activated.  In production code, the injected handler sends JMS messages to notify assigned users that work needs to be completed. Below is an example of a simple generated flow that fails intermittently for one developer here.  I captured it using the XmlRuleFlowProcessDumper. <?xml version="1.0" encoding="UTF-8"?> <process xmlns="http://drools.org/drools-5.0/process"         xmlns:xs="http://www.w3.org/2001/XMLSchema-instance"         xs:schemaLocation="http://drools.org/drools-5.0/process drools-processes-5.0.xsd"         type="RuleFlow" name="flow-1" id="bd5556f7_581d_422f_a382_3bb3ac041c4f" package-name="com.xxx.process.manager" >  <header>    <imports>      <import name="org.drools.ruleflow.instance.RuleFlowProcessInstance" />    </imports>  </header>  <nodes>    <start id="1" name="flow-1 Start" />    <join id="2" name="step-1 Reject Join" type="2" />    <workItem id="3" name="step-1 Step" >      <work name="Step" >      </work>    </workItem>    <workItem id="4" name="step-1 Approval" >      <work name="Step" >      </work>    </workItem>    <split id="5" name="step-1 Approval Split" type="2" >      <constraints>        <constraint toNodeId="2" toType="DROOLS_DEFAULT" name="rejected" priority="110" type="code" dialect="java" >return true;</constraint>        <constraint toNodeId="6" toType="DROOLS_DEFAULT" name="approved" priority="100" type="rule" dialect="mvel" >StepApproval( approved == true, sliceValue == "NO_SLICE", approvalStepNodeId == "1a8a5a64-1e32-46a9-8b04-806c1706a97a" )</constraint>      </constraints>    </split>    <state id="6" name="null Wait" >      <onEntry>        <action type="expression" dialect="java" >Terminator.terminateFlow(context);</action>      </onEntry>      <constraints>        <constraint toNodeId="7" >Terminator()</constraint>      </constraints>    </state>    <end id="7" name="null End" />  </nodes>  <connections>    <connection from="1" to="2" />    <connection from="5" to="2" />    <connection from="2" to="3" />    <connection from="3" to="4" />    <connection from="4" to="5" />    <connection from="5" to="6" />    <connection from="6" to="7" />  </connections> </process> I'm attaching the log at trace level (there are no WARN level messages at all) that shows this flow failing to complete.  Lines of interest: 631: Generating the flow from our internal model 634: starting the flow 785: Process event listener shows that flow has started and proceeded to work item 1 ("step-1 Step") 802: StepWorkItemHandler called for work item 1 "step-1 Step" 803: Process event listener shows "unwinding"of activations 904: Work item 1 "step-1 Step" completed 921: work item loaded 939: process instance loaded 956: Process event listener shows leaving "step-1 Step", activating work item 2 "step-1 Approval" 969: StepWorkItemHandler called forwork item 2 "step-1 Approval" 970: Process event listener shows "unwinding"of activations 1024: work item 1 deleted 1032: Work item 2 "step-1 Approval" completed 1049: work item loaded 1067: process instance loaded ---Should now see leaving "step-1 Approval" and completing flow, but don't see any further progress in the flow.--- 1141: work item 2 deleted The execution thread is part of the log output and it seems that everything is done in one thread. I've also attached a log file (without verbose hibernate output) for a successful test run. Regards, Dan Nathanson On Fri, Apr 1, 2011 at 2:42 AM, Mauricio Salatino <salaboy(a)gmail.com&gt; wrote: > Hi Dan, > That's strange, it could be related to a non updated version of the fluent > API. > Send us the logs with warn verbosity and we will definitely take a look on > it. > If the workflow don't continue after a work item completion could be related > with some kind of threading problem. > What kind of work item are you implementing? Can you share some test with us > that shows the desired behavior? > Greetings. > > On Thu, Mar 31, 2011 at 4:32 PM, Dan Nathanson <dan(a)ddnconsulting.com&gt; > wrote: >> >> Hi, >> >> I'm seeing some odd behavior in some of my test cases.  And it only >> seems to happen to one guy. And he's done fresh checkouts of the code, >> blown away his local M2 repository and verified installed software >> like OS and Java is same as everyone else's. >> >> I have some test cases that build up some simple flows programatically >> using fluent API.  Very simple (start --> work item --> work item --> >> state --> end).  I am using Drools Flow 5.1.1 with JPA (in-memory H2 >> DB for unit tests).  Intermittently, after completing a work item, the >> flow doesn't continue.  Logging in a process event listener shows that >> the the work item node is never left, although I can see in the logs >> that the work item is deleted from DB. >> >> There are no errors, warning or info level messages coming out of >> Drools or Hibernate prior to the failure. >> >> It only happens to one guy, but he can reproduce the problem >> regularly, although it moves around in different test cases and >> different points in the flows. >> >> Anyone ever seen this behavior before?  Any possible explanations? >> >> I'd attach the log file, but it is huge since I've got hibernate >> logging set very verbose. >> >> Regards, >> >> Dan Nathanson >> _______________________________________________ >> rules-users mailing list >> rules-users(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-users > > > > -- >  - CTO @ http://www.plugtree.com >  - MyJourney @ http://salaboy.wordpress.com >  - Co-Founder @ http://www.jbug.com.ar > >  - Salatino "Salaboy" Mauricio - >