topic Re: How a Callactiviti can access the parent process variables? in Alfresco Archive

How a Callactiviti can access the parent process variables?

purna_cherukuri — Fri, 29 Jun 2012 06:07:57 GMT

Hi,I am trying to use CallActiviti in my BPMN2.0 process. But I found it mandatory to pass the input variables to call Activiti as it runs in a child execution. Is there a way to pass whole set of parent execution's variables to Callactiviti without mentioning each and every one in bpmn2.0 xml? O

Re: How a Callactiviti can access the parent process variables?

frederikherema1 — Fri, 29 Jun 2012 07:03:33 GMT

Where do you want to use the process-variables? If you look on how activiti handles this, indeed a child-execution is created in the process-instance. In an expression or in a JavaDelegate you have the "execution" object available. If the variable is NOT defined on the execution itself (in this case, the callActivity execution), the parent is consulted. This goes up the execution-tree until a variable is found…

So just calling execution.getVariable("myVar") from within the callActivity execution will get you the values in the process…

The reason why the IN and OUT's are there, is because of the BPMN 2.0 spec. So this will only work in the activiti-engine, and is not explicit ally part of the spec

Re: How a Callactiviti can access the parent process variables?

purna_cherukuri — Fri, 29 Jun 2012 10:50:42 GMT

Thanks for the quick reply '@frederikheremans'.

What you are saying is a real good news for me if it works in the same manner. But it is not the case I am facing.
I have created a variable in parent execution and trying to access it from Callactiviti(child execution) and it is not working. It is returning null in that case.

I am using Activiti5.9. Could you please help on this?

Thank you.

Re: How a Callactiviti can access the parent process variables?

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Re: How a Callactiviti can access the parent process variables?

purna_cherukuri — Fri, 29 Jun 2012 13:59:11 GMT

I have debugged the code and identified that the child execution object created for CallActivity, doesnt contain the parentId. parentId is coming as "null". Which is causing the issue reported. Any help on this?

Please find my bpmn xml for reference.

<process id="AccountDetails" name="AccountDetails">
    <documentation>Place documentation for the 'AccountDetails' process here.</documentation>
    <startEvent id="startevent1" name="Start"></startEvent>
    <exclusiveGateway id="exclusivegateway1" name="Exclusive Gateway"></exclusiveGateway>
    <sequenceFlow id="flow1" name="" sourceRef="startevent1" targetRef="exclusivegateway1"></sequenceFlow>
    <serviceTask id="servicetask1" name="Get Asset Allocations" activiti:class="com.cgi.msuite.bpmn.wms.portfolios.tasks.GetAssetAllocationsTask"></serviceTask>
    <sequenceFlow id="flow5" name="" sourceRef="exclusivegateway1" targetRef="servicetask1">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${flow.equals("AssetAlloc")}]]></conditionExpression>
    </sequenceFlow>
    <serviceTask id="servicetask2" name="Get Account Transactions" activiti:class="com.cgi.msuite.bpmn.wms.portfolios.tasks.GetAccountTransactionsTask"></serviceTask>
    <sequenceFlow id="flow3" name="" sourceRef="exclusivegateway1" targetRef="servicetask2">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${flow.equals("Transactions")}]]></conditionExpression>
    </sequenceFlow>
    <serviceTask id="servicetask3" name="Get Account Positions" activiti:class="com.cgi.msuite.bpmn.wms.portfolios.tasks.GetAccountPositionsTask"></serviceTask>
    <sequenceFlow id="flow7" name="" sourceRef="exclusivegateway1" targetRef="servicetask3">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${flow.equals("Positions")}]]></conditionExpression>
    </sequenceFlow>
    <endEvent id="endevent1" name="End"></endEvent>
    <sequenceFlow id="flow6" name="" sourceRef="servicetask1" targetRef="endevent1"></sequenceFlow>
    <sequenceFlow id="flow4" name="" sourceRef="servicetask2" targetRef="endevent1"></sequenceFlow>
    <sequenceFlow id="flow8" name="" sourceRef="servicetask3" targetRef="endevent1"></sequenceFlow>
    <serviceTask id="servicetask8" name="Get Maturity Schedule" activiti:class="com.cgi.msuite.bpmn.wms.portfolios.tasks.GetAccountMaturityScheduleTask"></serviceTask>
    <sequenceFlow id="flow17" name="" sourceRef="exclusivegateway1" targetRef="servicetask8">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${flow.equals("MaturitySchedule")}]]></conditionExpression>
    </sequenceFlow>
    <sequenceFlow id="flow18" name="" sourceRef="servicetask8" targetRef="endevent1"></sequenceFlow>
    <callActivity id="callactivity1" name="Projected Income" calledElement="AccountProjectedIncome">
      <extensionElements>
        <activiti:in source="flow" target="flow"></activiti:in>
      </extensionElements>
    </callActivity>
    <sequenceFlow id="flow19" name="" sourceRef="exclusivegateway1" targetRef="callactivity1">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${flow.equals("QrtlyIncmProj")}]]></conditionExpression>
    </sequenceFlow>
    <sequenceFlow id="flow20" name="" sourceRef="callactivity1" targetRef="endevent1"></sequenceFlow>
  </process>

Thank you.

Re: How a Callactiviti can access the parent process variables?

frederikherema1 — Mon, 02 Jul 2012 14:52:19 GMT

If I look into the source-code, I see the super-process is being set on the created sub-process:

org.activiti.engine.impl.pvm.runtime.ExecutionImpl:139

public PvmProcessInstance createSubProcessInstance(PvmProcessDefinition processDefinition) {
    ExecutionImpl subProcessInstance = newExecution();
    
    // manage bidirectional super-subprocess relation
    subProcessInstance.setSuperExecution(this);
    this.setSubProcessInstance(subProcessInstance);
    
    // Initialize the new execution
    subProcessInstance.setProcessDefinition((ProcessDefinitionImpl) processDefinition);
    subProcessInstance.setProcessInstance(subProcessInstance);

    return subProcessInstance;
  }

Can you debug too see if the executionEntity has that field set?

Re: How a Callactiviti can access the parent process variables?

purna_cherukuri — Mon, 02 Jul 2012 15:09:31 GMT

Hi @frederikheremans,

I have debugged and checked. It is not coming to the method you specified at all.
Does it take same flow even in case of callactivity?

Thank you.

Re: How a Callactiviti can access the parent process variables?

frederikherema1 — Mon, 02 Jul 2012 15:25:16 GMT

Sorry, might have been the "ExecutionEntity" instead of Impl…

Re: How a Callactiviti can access the parent process variables?

purna_cherukuri — Mon, 02 Jul 2012 15:37:11 GMT

Yes, It is setting the superProcess details when creating the sub process instance. But as part of executing the getVariable method, it is looking for parentId which is null. So the it is returning parentScope as null in getVariable method.

Ideally superExecutionId is getting set properly but not parentId.

Re: How a Callactiviti can access the parent process variables?

purna_cherukuri — Wed, 08 Aug 2012 04:39:07 GMT

Somebody please reply on this, as this is very critical to complete my evaluation of different BPMN solutions.

Re: How a Callactiviti can access the parent process variables?

xseagullx — Tue, 21 Oct 2014 10:56:06 GMT

Hello
May I become a necromancer, and resurrect this thread? 😃

It seems, that problem still exists(at least in version 5.14). Root of it is, as previous persons noticed, that foe ExecutionEntry parent is null, only superProcess is valid.

So, Is it done intentionally, or it's a bug. In that case, what is the simplest workaround?

Regards,
Pavel

Re: How a Callactiviti can access the parent process variables?

jbarrez — Wed, 22 Oct 2014 10:53:06 GMT

Hehehe 'a necromancer' 🙂

What exactly in this thread are you referring to: the capability of passing all variables into a called subprocess?

Or the fact you cant reference process variables from a parent in a subprocess cause the parent is null?

Re: How a Callactiviti can access the parent process variables?

xseagullx — Thu, 23 Oct 2014 11:11:24 GMT

It has been said, that "If the variable is NOT defined on the execution itself (in this case, the callActivity execution), the parent is consulted. This goes up the execution-tree until a variable is found…"

But as it is implemented now, it's wrong. We have situations, when parent is null, and only superProcess is reffered up in the hierarchy.

So, I think, if frederikheremans's statement is true, in that case we have a bug, as we can't access superprocess variables from callActivity.

If it's done intensionally, ok, I will look for another way to solve my problem.

In fact, I have smth(String, document identificator) which is global during a process, and I'm looking an easy way to have access to it in every subsequent subprocess.

Re: How a Callactiviti can access the parent process variables?

jbarrez — Fri, 24 Oct 2014 06:40:10 GMT

Yes, I also believe it is a bug. It's kinda related to this: https://jira.codehaus.org/browse/ACT-1805
The correct way should indeed be that it searches up the super executions too … but i forsee a lot of side effects there.

Re: How a Callactiviti can access the parent process variables?

jcoveron — Mon, 07 Sep 2015 09:15:38 GMT

Greeting,

I am currently using Activiti 5.17. As I was testing a process which has a "Call Activity" action, I found the same issue as it is reported here. When the process flow enters the process represented by the "Call Activity", I can see that execution parent and parentId are null.

However, if the "Call Activity" is replaced by an embedded subprocess, I can see that the execution variable has correct values. For instance execution.parent equals ExecutionEntity and execution.parentId equals a specific id.

In both case scenarios, the process flow never enters function createSubProcessInstance in org.activiti.engine.impl.pvm.runtime.ExecutionImpl.

I did check the release notes for Activiti 5.18 and I see that this jira ACT-1805 has not been fixed. So, I was wondering if you had plans to fix this bug any time soon, and if in the mean time there is a workaround.

Many thanks in advance.

Re: How a Callactiviti can access the parent process variables?

jbarrez — Tue, 08 Sep 2015 09:11:39 GMT

It's an old thread, so my memory is a bit fuzzy here.
But a call activity normally does not inherit variables, hence why it has an input/output mapping.
So variables are not automatically available for call activities (cause they can have different names in the called process, they need a dedicated mapping).

Or am i totally misinterpreting the issue here?

Re: How a Callactiviti can access the parent process variables?

jcoveron — Tue, 08 Sep 2015 11:11:44 GMT

Hi Joram

Thanks for replying. this fast.

According to Frederik in one of his replies: "If the variable is NOT defined on the execution itself (in this case, the callActivity execution), the parent is consulted. This goes up the execution-tree until a variable is found… The reason why the IN and OUT's are there, is because of the BPMN 2.0 spec. So this will only work in the activiti-engine, and is not explicitally part of the spec".

However, since the parent Id is null, there is no way to climb up the execution-tree. But in the case of an embedded subprocess, there is no problem. Based on your answer and what I have found, this is not the case.

So, I was wondering if this is actually a bug which has not been fixed and if there is a workaround.

Many thanks in advance.

Best regards,

Re: How a Callactiviti can access the parent process variables?

jbarrez — Tue, 15 Sep 2015 10:28:28 GMT

It's been a year since I said that, people can change ideas based on what they've learned 😉

Currently, I'm actually not sure it should automatically go up the chain of parents, I'm more a fan of explicitly mapping it into the called process now instead of relying on it explicitly.

Re: How a Callactiviti can access the parent process variables?

midiman — Mon, 26 Sep 2016 21:44:56 GMT

Hi,
I know this a bit of an old post - but it's still very relevant.

Is there a way to optionally either auto-import all parent variables to subprocess variables (maybe via the cfg.xml?), or maybe a wildcard in the model, like in=* out=*?

If you can point me to the place in the code where such an inheritance might take place, I'm happy to have a go at putting it in, then publish it for the benefit of others.

I'm using 5.21 currently.

Many thanks,
Peter

Re: How a Callactiviti can access the parent process variables?

warper — Tue, 27 Sep 2016 09:53:36 GMT

Hi Peter!
You can create java delegate that gets all process variables and puts them into one map. Put it into input expression and output expression of c all activity.
You can create another java delegate that goes through such map and sets process variables accordingly. Put it after start event of subprocess and after call activity step