django-model-versions 0.4.0

A base model class for adding version information and preventing concurrent modifications

django-model-versions

A library for adding version information to models. This version information is then used to prevent concurrent modifications. E.g.

>>> b1 = Blog.objects.get(id=1)
>>> b2 = Blog.objects.get(id=1) # Same row as b1
>>> b1.title = 'Some blog'
>>> b1.save()
>>> b2.title = 'Some other blog'
>>> b2.save()

Will result in a ConcurrentModificationException being raised instead of overriding the data saved by b1.

Usage

Subclass modelversions.VersionedModel instead of django.db.models.Model. That’s it!

Known flaws

objects.update(…) will not increment the version number for objects altered. This would be better as a mixin. object.delete() will not check versioning Django admin hates it

Author

Colin Howe <[e-mail]> http://www.colinhowe.co.uk - @colinhowe