Creating migrations for auth app in django

Question

I need to add a couple fields to Group model in django contrib.auth app using:

field_name = models.CharField(...)
field_name.contribute_to_class(Group, 'field_name')

My issue is while creating the migrations with South, since they are created in the "migrations" directory inside the auth app and, since the system is already in production, I'm not allowed to alter the current django installation in the server in order to migrate auth.

Does anyone know how to create and load such migrations?

Thanks in advance for your help.

Answer 1

Django doesn't make it particularly easy to modify the standard models. I wouldn't recommend that you sublass Group, because it's quite annoying to get built-in functionality to reference the new model instead.

The usual thing to do here is to create a GroupProfile model that has a Group as a unique foreign key. It might not be elegant, but it won't have the huge maintenance overhead that comes with forking Django's source code.

Also: if you can't modify the Django code on the server, you aren't going to be able to do this with raw SQL hackery or a clever migration. South isn't going to be the problem -- the problem is that the Django ORM is going to notice that there are fields present in the SQL table that aren't specified in the code, which will cause it to throw an exception.

Answer 2

Since you use a hack to patch up the model, I think you should write a migration manually. Try copying another migration and changing add_column and models first, if it fails - there is always an option named "raw sql" :)