L3 - Default Environment (Required on creation): Camunda 7.16.0
Description (Required on creation; please attach any relevant screenshots, stacktraces, log files, etc. to the ticket):
I assign a task to the username "" (empty String) via API. The task in the tasklist shows up as "unassigned" because I have the option to click "Claim task". If I click "Claim task" there is an error message "Task '68d43e94-187a-11ed-bfb3-f40270f6362c' is already claimed by someone else." There is no option to reassign the task in the tasklist.
Steps to reproduce (Required on creation):
- Update task via API, set username to "".
- Open Tasklist and "Claim task".
Observed Behavior (Required on creation):
There is an error message. I cant unassign or reassign the task.
Expected behavior (Required on creation):
The task in the tasklist should show as assigned.
Root Cause (Required on prioritization):
Handling of empty string for field "assignee" is handled improperly.
Solution Ideas (Optional):
Dont allow "" as valid username.
OR
Treat "" as a valid username in tasklist.
Hints (optional):
When filtering the tasks by "assigned" (true/false) via REST API the task with assignee "" is interpreted as assigned.