topic Re: User Task Rollback in Alfresco Archive

User Task Rollback

javedafroz — Mon, 20 Apr 2015 12:25:32 GMT

Hi,I am considering activiti 5.15 for designing business process for one of RFP. The process is pretty straight forward, it consists of number of "User Taks" with role based assignments. However there is one requirement from client which I am unable to map to Activiti features. Client wants that an

Re: User Task Rollback

martin_grofcik — Tue, 21 Apr 2015 06:30:38 GMT

Hi Javed,

I see 2 possibilities:

process design - you can change process design to allow return from D to A,B,C. (use exclusion gateway based on decision taken in D)
change execution activity to the A,B,C - there is no API for that but implementation is simple.

Regards
Martin

Re: User Task Rollback

javedafroz — Wed, 13 May 2015 06:51:02 GMT

Hi Martin,

I tried with your first suggestion of changing "process design" to accommodate possible rollbacks, but the problem I am facing is that the number of executions exponentially rise due to multiple possible rollbacks. This is resulting in very complex workflow process definition.

Can you elaborate a little bit more on second suggestion? How can I change execution activity at runtime?

Regards,
Javed

Re: User Task Rollback

trademak — Wed, 13 May 2015 12:15:35 GMT

Hi Javed,

It's possible to change the activity id of an execution and therefore it's possible to move the state back to another user task.
We don't support this through our api currently, but it's possible to write a custom command to accomplish this.

Best regards,

Re: User Task Rollback

javedafroz — Wed, 13 May 2015 12:47:17 GMT

Hi,

So, are you suggesting to update the underlying database directly? Won't there be any repercussions?

Regards,
Javed

Re: User Task Rollback

jbarrez — Mon, 18 May 2015 14:59:58 GMT

No, Tijs suggested writing a Command (see managementService.executeCommand) to do that.

Re: User Task Rollback

javedafroz — Mon, 18 May 2015 15:39:28 GMT

Thanks JBarrez, I will check that. My question is if I go by the suggested workaround (since there is no direct APIs to achieve it), will there be any side effects? For example - will process history include the execution changes done through managementService.executeCommand ?

Re: User Task Rollback

jbarrez — Tue, 26 May 2015 08:03:46 GMT

No, it won't be, unless you add it to your logic.

Re: User Task Rollback

ware4u — Sun, 22 Jan 2017 06:42:33 GMT

is any code snippet for this question?

Re: User Task Rollback

gdharley — Thu, 26 Jan 2017 20:16:28 GMT

Something like this should work....

1. create a command:

/**
 * @author Greg Harley - BP3
 */
public class MoveTokenCmd implements Command<Void>, Serializable {

  private static final long serialVersionUID = 1L;
  protected String executionId;
  protected String targetActivityId;

  public MoveTokenCmd(String executionId, String targetActivityId) {
    this.executionId = executionId;
    this.targetActivityId = targetActivityId;
  }

  public Void execute(CommandContext commandContext) {
    ExecutionEntity execution = commandContext.getExecutionEntityManager().findExecutionById(this.executionId);
    execution.setActivity(execution.getProcessDefinition().findActivity(this.targetActivityId));
    AtomicOperation.TRANSITION_CREATE_SCOPE.execute(execution);
    
    
    return null;
  }

}

2. Call the command from the management service:

// Set the new activity

managementService.executeCommand(new MoveTokenCmd(executionId, targetActivityId));

Obviously you will need to have the target activity id and execution id, but I will leave that for you to handle.

Cheers,

Greg

‌

Re: User Task Rollback

prasanna_mondka — Mon, 03 Apr 2017 15:43:48 GMT

Hi Greg,

I have a process Task 1 -> Task 2 -> Task 3 (all user tasks).

When, i reached at [Task 3] through normal execution, I used the above custom command to jump to [Task 1], and it worked.

But, when i queried the Task Service for current running tasks of this process, i got both [Task 3] and [Task 1].

So, when the Activiti Execution Id is reset, the previous task is kept running ?

Our logic needs only task running at any given moment, so i tried deleting Task 3, but i got ActivitiException (The task cannot be deleted because is part of a running process).

I also tried marking [Task 3] as complete, but got another ActivitiException (UserTask should not be signalled before complete)

Is there any other way (like deleting, maybe) ?

Hope i am not asking something silly 🙂

Re: User Task Rollback

prasanna_mondka — Mon, 03 Apr 2017 18:43:33 GMT

Alright.

I solved this by deleting the Task (TaskEntity object is needed), from Execution Context, by using [TaskEntitytManager], in the Custom command itself.
Following is the code that I added to the execute method, after the execution.setActivity(..) line ...

final TaskEntity currentUserTaskEntity = commandContext.getTaskEntityManager().findTaskById(this.currentUserTask.getId());

currentUserTaskEntity.setExecutionId(null); // To overcome the "Task cannot be deleted because is part of a running process"
processcommandContext.getTaskEntityManager().deleteTask(this.currentUserTask.getId(), "jumped to another task", true);

where, [currentUserTask] is an object of type [Task] (unlike greg's code, where it is a string)

I also confirmed, that [Task 3] (the deleted Task) is only deleted from the execution context and not from the Model itself, i.e.,In my test case, after jumping back to [Task 1], I again followed normal execution (complete current task and move ahead), to see that [Task 3] is indeed picked up for execution again.

Hope I am not doing anything wrong here. Can you please check and confirm.

Also, I would be very very thankful to you, if you can point out any potential problems in Execution of the process, if there are any.

Re: User Task Rollback

gdharley — Mon, 03 Apr 2017 19:33:35 GMT

Nice work, I think you have everything covered.

Cheers,

Greg

‌