Activiti > bpmn : not able to assign candidate group dynamically using variables

[Indrayani Godbole]

Hi,

I am running activiti from liferay.
I am trying to set candidate group for user task dynamically for which I have tried below solutions which are not working.
This is for liferay 6.2 CE GA6 and activiti version 5.18.0
Please let me know if I have missed anything or If you have a better solution.

Solution 1 :
Its regarding settting candidate group for a user task using proccess variable.
below is the bpmn code :

  <userTask id="Review" name="Review"  activiti:candidateGroups=${assignee}>
      <extensionElements>
        <activiti:formProperty id="outputTransition" name="output Transition" type="enum">
          <activiti:value id="Approve" name="Approve"></activiti:value>
          <activiti:value id="Reject" name="Reject"></activiti:value>
        </activiti:formProperty>
      </extensionElements>
    </userTask>

here , assignee is the process variable which is already set.

While executing the workflow, I am getting following exception :

13:42:01,326 INFO  [http-bio-8080-exec-10][LiferayGroupsUtil:54] Convert groups : [ ${assignee} ]
13:42:01,329 WARN  [http-bio-8080-exec-10][LiferayGroupsUtil:94] Cannot assign task to role ${assignee}
com.liferay.portal.NoSuchRoleException: No Role exists with the key {companyId=20155, name=${assignee}}

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Solution 2 :

I also tried below xml code but I am still getting the same exception :
Here, I have the multiInstanceLoopCharacteristics.

 <userTask id="Review" name="Review"  activiti:candidateGroups=${assignee}>
	    <multiInstanceLoopCharacteristics isSequential="false" 
	     activiti:collection="candidateGrp" activiti:elementVariable="assignee" >
	    <completionCondition>${nrOfCompletedInstances/nrOfInstances >= 0.6 }</completionCondition>
	  </multiInstanceLoopCharacteristics>
      <extensionElements>
        <activiti:formProperty id="outputTransition" name="output Transition" type="enum">
          <activiti:value id="Approve" name="Approve"></activiti:value>
          <activiti:value id="Reject" name="Reject"></activiti:value>
        </activiti:formProperty>
      </extensionElements>
    </userTask>

------------------------------------------------------------------------------------------
Solution 3:

I also tried to set the candidate group dynmically using DynamicBpmnService, Please check the code below :
For this approach, I used activiti version 5.19.0
I replaced the activiti engine jar from liferay > tomcat> webapp > activiti-web > web-inf >lib

	@Override
	public void notify(DelegateExecution execution) {
		try {
		EngineServices engineServices = execution.getEngineServices();
		DynamicBpmnService dynamicBpmnService = engineServices.getDynamicBpmnService();
		ObjectNode infoNode = dynamicBpmnService.changeUserTaskCandidateGroup(
			      "Review", "Power User", false);
		dynamicBpmnService.saveProcessDefinitionInfo("procDefId", infoNode);
		System.out.println("------saveProcessDefinitionInfo------=saved");
		
		} catch (Exception e) {
			System.out.println("------error");
			e.printStackTrace();
		}
		List<String> list = new ArrayList<String>();
		list.add("Power User");
		execution.setVariable("candidateGrp",list);
	}

I am getting following exception while executing this code :

WARN  [http-bio-8080-exec-10][ProxyMessageListener:81] org.apache.ibatis.exceptions.PersistenceException: 
### Error updating database.  Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails (`lportal`.`act_procdef_info`, CONSTRAINT `ACT_FK_INFO_PROCDEF` FOREIGN KEY (`PROC_DEF_ID_`) REFERENCES `act_re_procdef` (`ID_`))
### The error may involve org.activiti.engine.impl.persistence.entity.ProcessDefinitionInfoEntity.insertProcessDefinitionInfo-Inline
### The error occurred while setting parameters
### SQL: insert into ACT_PROCDEF_INFO(ID_, PROC_DEF_ID_, REV_, INFO_JSON_ID_)     values(?,             ?,            1,            ?)
### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails (`lportal`.`act_procdef_info`, CONSTRAINT `ACT_FK_INFO_PROCDEF` FOREIGN KEY (`PROC_DEF_ID_`) REFERENCES `act_re_procdef` (`ID_`))
org.apache.ibatis.exceptions.PersistenceException: 
### Error updating database.  Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails (`lportal`.`act_procdef_info`, CONSTRAINT `ACT_FK_INFO_PROCDEF` FOREIGN KEY (`PROC_DEF_ID_`) REFERENCES `act_re_procdef` (`ID_`))
### The error may involve org.activiti.engine.impl.persistence.entity.ProcessDefinitionInfoEntity.insertProcessDefinitionInfo-Inline
### The error occurred while setting parameters
### SQL: insert into ACT_PROCDEF_INFO(ID_, PROC_DEF_ID_, REV_, INFO_JSON_ID_)     values(?,             ?,            1,            ?)
### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails (`lportal`.`act_procdef_info`, CONSTRAINT `ACT_FK_INFO_PROCDEF` FOREIGN KEY (`PROC_DEF_ID_`) REFERENCES `act_re_procdef` (`ID_`))

I am really stuck at this point and not able to proceed.
So your quick help would be appreciated.

Thank you