Add/update candidate group to existing task

Camunda 7 Topics Discussion & Questions
1

Hello,
I am trying to add candidate group to an existing task. It seems there is no direct method available in Java APIs to set candidateGroup to a task.

However I found that there is a REST API which does the same…

https://docs.camunda.org/manual/latest/reference/rest/task/identity-links/post-identity-link/

Does anyone have any corresponding code snippet to achieve the same through code.

Or any other way to set candidate group on a task programmatically.

2

Hi @Ashish_Pingale, Below code is used in the TaskListener implementation.

To set assignee:

delegateTask.setAssignee((String) delegateTask.getVariable(assignee));

To set candidate users:

private void updateCandidateUsersForTask(DelegateTask delegateTask, TaskEventRequest taskEventRequest) {
    if (StringUtils.hasText(taskEventRequest.getCandidateUsers())
        && WorkflowUtil.hasProcessVariable(delegateTask.getExecution(), taskEventRequest.getCandidateUsers())) {
      log.info("Update CandidateUser for task:{}, name:{}", delegateTask.getId(), delegateTask.getTaskDefinitionKey());
      Set<IdentityLink> identityLinks = delegateTask.getCandidates();
      if (!identityLinks.isEmpty()) {
        identityLinks.stream().filter(identityLink -> IdentityLinkType.CANDIDATE.equals(identityLink.getType())
            && identityLink.getUserId() != null).forEach(identityLink -> {
              log.info("Task " + delegateTask.getId() + " has an identity link for a user with id: "
                  + identityLink.getUserId());
              delegateTask.deleteUserIdentityLink(identityLink.getUserId(), IdentityLinkType.CANDIDATE);
            });
      }
      String candidateUsers = (String) delegateTask.getExecution().getVariable(taskEventRequest.getCandidateUsers());
      if (StringUtils.hasText(candidateUsers) && candidateUsers.lastIndexOf(',') > 0) {
        Collection<String> candidateUsersList = Arrays.asList(candidateUsers.split(","));
        delegateTask.addCandidateUsers(candidateUsersList);
      } else {
        delegateTask.addCandidateUser(candidateUsers);
      }
    }
  }

To set candidate groups:

private void updateCandidateGroupsForTask(DelegateTask delegateTask, TaskEventRequest taskEventRequest) {
    if (StringUtils.hasText(taskEventRequest.getCandidateGroups())
        && WorkflowUtil.hasProcessVariable(delegateTask.getExecution(), taskEventRequest.getCandidateGroups())) {
      log.info("Update CandidateGroup for task:{}, name:{}", delegateTask.getId(), delegateTask.getTaskDefinitionKey());
      Set<IdentityLink> identityLinks = delegateTask.getCandidates();
      if (!identityLinks.isEmpty()) {
        identityLinks.stream().filter(identityLink -> IdentityLinkType.CANDIDATE.equals(identityLink.getType())
            && identityLink.getGroupId() != null).forEach(identityLink -> {
              log.info("Task " + delegateTask.getId() + " has an identity link for a group with id: "
                  + identityLink.getGroupId());
              delegateTask.deleteGroupIdentityLink(identityLink.getGroupId(), IdentityLinkType.CANDIDATE);
            });
      }
      String candidateGroups = (String) delegateTask.getExecution().getVariable(taskEventRequest.getCandidateGroups());
      if (StringUtils.hasText(candidateGroups) && candidateGroups.lastIndexOf(',') > 0) {
        Collection<String> candidateGroupList = Arrays.asList(candidateGroups.split(","));
        delegateTask.addCandidateGroups(candidateGroupList);
      } else {
        delegateTask.addCandidateGroup(candidateGroups);
      }
    }
  }
3

Hi Aravindh,
This is useful.
Any idea how to get DelegateTask from Task. I Have the following code:

@Override
public void execute(DelegateExecution execution) throws Exception {

TaskQuery queryTasks = execution.getProcessEngineServices().getTaskService().createTaskQuery().processInstanceId(execution.getProcessInstanceId());
Task myTask = queryTasks.taskName(“Perform Processing”).singleResult();
// SET CANDIDATE GROUP HERE
}

5

Here’s the code:

public void execute(DelegateExecution execution) throws Exception {    
    TaskService taskService = execution.getProcessEngineServices().getTaskService();
    Task task = taskService.createTaskQuery().processDefinitionKey(execution.getProcessDefinitionKey())
        .processInstanceBusinessKey(execution.getProcessBusinessKey()).singleResult();
    taskService.addCandidateGroup(task.getId(), "candidateGroup");
    taskService.addCandidateUser(task.getId(), "candidateUser");
    taskService.setAssignee(task.getId(), "assignee");
}
6

Thanks that works.

7

Is there a way to add multiple candidate users/groups as a list? TaskService just lets you add a single entry at a time. Basically, I want to avoid the listener being invoked for every candidate user insertion.