Protector

Protector is used for managing object level permissions in performance efficient way. It supports queryset filtering by permission and user. Also it allow every object in your project to behave as a user group. i.e. adding permissions and users with roles.

Quick start

1. Install from pip (it will also install required django-mptt):

   pip install django-protector
   

2. Add "protector" to your INSTALLED_APPS setting:

   INSTALLED_APPS = (
       ...
       'protector',
   )
   

3. Add protector authentication backend. Also you should remove default auth backend:

   AUTHENTICATION_BACKENDS = (
       ...
       'protector.backends.GenericPermissionBackend'
   )
   

4. Make some model your default group:

   PROTECTOR_GENERIC_GROUP = 'users.group'
   

5. Run python manage.py migrate to create the protector models and copy existing user permissions

Now you can check permissions on objects like this:

user.has_perm('some_app.some_perm', user)

Or filter any queryset by permission:

from protector.models import filter_queryset_by_permission
filtered_qset = filter_queryset_by_permission(some_qset, user, 'some_app.some_perm')

Additional steps

1. Add GenericPermsMixin to your User model to conviniently add permissions and groups:

   class User(UserGenericPermsMixin, AbstractBaseUser)
   

2. Create some group models. Every model in your project could now behave like a group. You could inherit your models from abstract group to have convinient fields for users and permissions:

   class Group(AbstractGenericGroup):
   

4. Inherit your Querysets from PermissionQuerySet to conviniently filter by permission:

   some_qset.filter_by_permission(user, 'some_app.some_perm')
   

Now you can manipulate permissions and groups:

user.permissions.all()
user.permissions.add(permission)
user.groups.all()
group.permissions.add(permission)

Restricting access to objects

This is somewhat different from just filtering queryset by permission

1. Inherit your model from Restricted:

   class Comment(Restricted)
   

2. Inherit model manager from RestrictedManager:

   class CommentManager(RestrictedManager):
   

3. Restricted contains some additional fields so you need to run makemigration for your app

4. Now you can restrict instances of your model:

   comment.restrict()
   

To enable user view one or all restricted objects:

user.permissions.add(Restricted.get_view_permission(), comment)
user.permissions.add(Restricted.get_view_permission())

To filter model objects visible by user:

Comment.objects.visible(user)