jBPM 6.1 Human Task REST Start/Complete

Question

I'm trying to make a REST POST call to Start a Human Task with this:

http://Administrator:superman@bpm.server.com/jbpm-console/rest/task/1/start

The taskId 1 is actually Reserved by the user john.doe, and when I execute the call the server responds with a status: 406 - Conflict

I read in the documentation that the Administrator user is allowed to perform all actions for the tasks.

Do I have to pass another parameter indicating which userId is performing the action, besides the one who is executing the REST call? Do anyone knows how the parameter is called? Tried all the obvious names and still throws an error. Thanks.

EDIT:

I'm adding the server response:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
  <exception>
    <status>PERMISSIONS_CONFLICT</status>
    <url>http://127.0.0.1:8080/jbpm-console/rest/task/1/start</url>
    <message>PermissionDeniedException thrown with message 'User '[UserImpl:'bc-admin']' does not have permissions to execute operation 'Start' on task id 1'</message>
    <stackTrace>org.kie.workbench.common.services.rest.RestOperationException: User '[UserImpl:'bc-admin']' does not have permissions to execute operation 'Start' on task id 1
    ...

EDIT 2:

The Tasks properties are:

"people-assignments":{
  "potential-owner":[
    {"id":"HR","type":"GROUP"},
    {"id":"user@company.com","type":"USER"}],
  "business-administrator":[
    {"id":"Administrator","type":"USER"},
    {"id":"Administrators","type":"GROUP"}],
  "excluded-owners":[],
  "task-stakeholders":[],
  "recipients":[]}
  ...

Thanks in advance.

Answer 1

Finally and after a long long cry, I had to fork the REST API and add the functionality to it because it's missing.