Fix RecursionError: maximum recursion depth exceeded in Django

This error occurs when a function calls itself infinitely, exceeding Python's default recursion limit of 1000 frames. In Django, this commonly happens with overridden save() methods that call self.save(), circular signal handlers, or serializers with nested relationships. Fix it by breaking the cycle with conditional checks or using update() instead.

Reading the Stack Trace

Here's what each line means:

• File "/app/src/models.py", line 32, in save: The overridden save() method on the model calls self.save() instead of super().save(), creating an infinite loop.
• [Previous line repeated 995 more times]: Python detected the same stack frame repeating 995 additional times, hitting the default recursion limit of 1000.
• File "/app/src/views.py", line 18, in update_profile: The view function triggered the save, which started the infinite recursion chain.

Common Causes

class Profile(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    bio = models.TextField(blank=True)
    updated_at = models.DateTimeField(auto_now=True)

    def save(self, *args, **kwargs):
        self.bio = self.bio.strip()
        self.save(*args, **kwargs)  # Bug: should be super().save()

from django.db.models.signals import post_save
from django.dispatch import receiver

@receiver(post_save, sender=Profile)
def update_profile_timestamp(sender, instance, **kwargs):
    instance.updated_at = timezone.now()
    instance.save()  # Triggers post_save again

The Fix

Replace self.save() with super().save() to call the parent class's save method instead of recursively calling the overridden method. This preserves the custom logic while correctly persisting to the database.

class Profile(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    bio = models.TextField(blank=True)
    updated_at = models.DateTimeField(auto_now=True)

    def save(self, *args, **kwargs):
        self.bio = self.bio.strip()
        self.save(*args, **kwargs)

class Profile(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    bio = models.TextField(blank=True)
    updated_at = models.DateTimeField(auto_now=True)

    def save(self, *args, **kwargs):
        self.bio = self.bio.strip()
        super().save(*args, **kwargs)

Testing the Fix

import pytest
from django.contrib.auth.models import User
from models import Profile


@pytest.mark.django_db
def test_profile_save_does_not_recurse():
    user = User.objects.create_user(username='alice', password='testpass')
    profile = Profile(user=user, bio='  Hello World  ')
    profile.save()  # Should not raise RecursionError
    profile.refresh_from_db()
    assert profile.bio == 'Hello World'


@pytest.mark.django_db
def test_profile_save_strips_whitespace():
    user = User.objects.create_user(username='bob', password='testpass')
    profile = Profile(user=user, bio='  Spaces everywhere  ')
    profile.save()
    profile.refresh_from_db()
    assert profile.bio == 'Spaces everywhere'


@pytest.mark.django_db
def test_profile_save_updates_existing():
    user = User.objects.create_user(username='carol', password='testpass')
    profile = Profile.objects.create(user=user, bio='Original')
    profile.bio = '  Updated  '
    profile.save()
    profile.refresh_from_db()
    assert profile.bio == 'Updated'

Run your tests:

pytest

Pushing Through CI/CD

git checkout -b fix/recursion-error-save,git add src/models.py tests/test_models.py,git commit -m "fix: call super().save() instead of self.save() to prevent recursion",git push origin fix/recursion-error-save

Your CI config should look something like this:

name: CI
on:
  pull_request:
    branches: [main]
jobs:
  test:
    runs-on: ubuntu-latest
    services:
      postgres:
        image: postgres:15
        env:
          POSTGRES_DB: test_db
          POSTGRES_USER: postgres
          POSTGRES_PASSWORD: postgres
        ports:
          - 5432:5432
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-python@v5
        with:
          python-version: '3.11'
      - run: pip install -r requirements.txt
      - run: pytest --tb=short
        env:
          DATABASE_URL: postgres://postgres:postgres@localhost:5432/test_db

The Full Manual Process: 18 Steps

Here's every step you just went through to fix this one bug:

1. Notice the error alert or see it in your monitoring tool
2. Open the error dashboard and read the stack trace
3. Identify the file and line number from the stack trace
4. Open your IDE and navigate to the file
5. Read the surrounding code to understand context
6. Reproduce the error locally
7. Identify the root cause
8. Write the fix
9. Run the test suite locally
10. Fix any failing tests
11. Write new tests covering the edge case
12. Run the full test suite again
13. Create a new git branch
14. Commit and push your changes
15. Open a pull request
16. Wait for code review
17. Merge and deploy to production
18. Monitor production to confirm the error is resolved

Total time: 30-60 minutes. For one bug.

pip install bugstack

import bugstack

bugstack.init(api_key=os.environ["BUGSTACK_API_KEY"])

Deploying the Fix (Manual Path)

1. Run pytest locally to confirm save() works without recursion.
2. Open a pull request with the super().save() fix.
3. Wait for CI checks to pass on the PR.
4. Have a teammate review the model's save method.
5. Merge to main and verify profile updates work correctly in staging.

Frequently Asked Questions