Easiest way to rename a model using Django/South?

Question

I\'ve been hunting for an answer to this on South\'s site, Google, and SO, but couldn\'t find a simple way to do this.

I want to rename a Django model using South.

Answer 1

To answer your first question, the simple model/table rename is pretty straightforward. Run the command:

./manage.py schemamigration yourapp rename_foo_to_bar --empty

(Update 2: try --auto instead of --empty to avoid the warning below. Thanks to @KFB for the tip.)

If you're using an older version of south, you'll need startmigration instead of schemamigration.

Then manually edit the migration file to look like this:

class Migration(SchemaMigration):

    def forwards(self, orm):
        db.rename_table('yourapp_foo', 'yourapp_bar')


    def backwards(self, orm):
        db.rename_table('yourapp_bar','yourapp_foo')   

You can accomplish this more simply using the db_table Meta option in your model class. But every time you do that, you increase the legacy weight of your codebase -- having class names differ from table names makes your code harder to understand and maintain. I fully support doing simple refactorings like this for the sake of clarity.

(update) I just tried this in production, and got a strange warning when I went to apply the migration. It said:

The following content types are stale and need to be deleted:

    yourapp | foo

Any objects related to these content types by a foreign key will also
be deleted. Are you sure you want to delete these content types?
If you're unsure, answer 'no'.

I answered "no" and everything seemed to be fine.