How to prevent Django from generating migrations when using dynamic GoogleCloudStorage in a FileField?

We’re working on a Django project that stores video files in Google Cloud Storage using a FileField.

In our model, we define a default bucket storage like this:

from storages.backends.gcloud import GoogleCloudStorage
from django.conf import settings

DEFAULT_STORAGE = GoogleCloudStorage(bucket_name=settings.DEFAULT_GCS_BUCKET)

class Recording(models.Model):
    raw_file_gcp = models.FileField(blank=True, null=True, storage=DEFAULT_STORAGE)

However, in some parts of the system, we move files between two different GCS buckets:

  • One for regular usage (e.g. default-bucket)
  • Another for retention or archival purposes (e.g. retention-bucket)

To do that, we dynamically update the .name attribute of the file based on logic in the backend:

recording.raw_file_gcp.name = path_with_retention_bucket
recording.save(update_fields=["raw_file_gcp", "updated_at"])

Because the underlying storage class contains a bucket name, every time we run makemigrations, Django detects a change and adds a migration like this:

migrations.AlterField(
    model_name='recording',
    name='raw_file_gcp',
    field=models.FileField(blank=True, null=True, storage=myapp.models.CustomStorage(bucket_name='default-bucket')),
)

But nothing has actually changed in the model.

To avoid these unnecessary AlterField migrations, we implemented a custom storage class using @deconstructible and __eq__:

from django.utils.deconstruct import deconstructible
from storages.backends.gcloud import GoogleCloudStorage

@deconstructible
class NeutralGCSStorage(GoogleCloudStorage):
    def __eq__(self, other):
        return isinstance(other, NeutralGCSStorage)

And then used:

DEFAULT_STORAGE = NeutralGCSStorage(bucket_name=settings.DEFAULT_GCS_BUCKET)

But Django still generates the same migration, and doesn’t treat the storage as unchanged.

❓ What we’re looking for

How can we prevent Django from generating migrations when the only difference is the dynamic storage bucket used in a FileField?

✅ Context

  • Django 5.x
  • django-storages with GoogleCloudStorage backend
  • makemigrations is being run normally in CI and local dev
  • The only field triggering these migrations is a FileField with dynamic bucket logic
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