[Django 1.3] Restrict authors, in admin, to Super Users and Staff only.

admin.py

from django.contrib.auth.models import User
from django.contrib import admin
from dox.models import Page

#--------------------------------------------------------------------------
#
# Admin models:
#
#--------------------------------------------------------------------------

class PageAdmin(admin.ModelAdmin):
    
    #----------------------------------
    # Fields:
    #----------------------------------
    
    fields = ('author',)
    
    #----------------------------------
    # Methods:
    #----------------------------------
    
    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        """
        Restrict the list of authors to Super Users and Staff only.
        """
        if db_field.name == 'author':
            kwargs['queryset'] = User.objects.filter(is_staff=True, is_superuser=True)
        
        return super(PageAdmin, self).formfield_for_foreignkey(db_field, request, **kwargs)

#--------------------------------------------------------------------------
#
# Registrations:
#
#--------------------------------------------------------------------------

admin.site.register(Page, PageAdmin)

models.py

from django.db import models
from django.contrib.auth.models import User

class Page(models.Model):
    
    author = models.ForeignKey(User, blank=True, null=True, help_text=_(u'Optional (used for organizational purposes only).'),)
    
    # ...