Flagsmith/flagsmith

Race condition in deleting segments

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#7354 opened on Apr 27, 2026

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 (0 comments) (0 reactions) (0 assignees)Python (3,475 stars) (264 forks)batch import
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Description

Acceptance Criterion

  • The asynchronous task delete_segment ignores it when the segment is already deleted.

Sentry Issue: FLAGSMITH-API-5NB

Segment.DoesNotExist: Segment matching query does not exist.
(3 additional frame(s) were not displayed)
...
  File "segments/tasks.py", line 14, in delete_segment
    Segment.objects.get(pk=segment_id).delete()

Failed to execute task 'tasks.delete_segment', with id 410046727. Exception: Segment matching query does not exist.

Contributor guide

Tech stack
python
Domain
backend
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Python
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70
Research direction
The bug occurs in `segments/tasks.py` at line 14 where `Segment.objects.get(pk=segment id).delete()` is called without checking if the segment exists. The fix is to use a try/except block to catch `Segment.DoesNotExist` and silently ignore it, or to use `get object or 404` and handle the exception. Review the `delete segment` task and implement a check for existence before deletion.