Implement per site restriction for users

tests/test_utils/admin.py

@@ -0,0 +1,22 @@
+# -*- coding: utf-8 -*-
+from django.contrib import admin
+from django.contrib.auth.admin import UserAdmin
+from django.utils.translation import ugettext_lazy as _
+
+from .models import CustomUser
+
+
+class CustomUserAdmin(UserAdmin):
+    model = CustomUser
+
+
+    fieldsets = (
+        (None, {'fields': ('username', 'password')}),
+        (_('Personal info'), {'fields': ('first_name', 'last_name', 'email')}),
+        (_('Permissions'), {'fields': ('is_active', 'is_staff', 'is_superuser',
+                                       'groups', 'user_permissions')}),
+        (_('Important dates'), {'fields': ('last_login', 'date_joined')}),
+        (_('Sites'), {'fields': ('sites',)})
+    )
+
+admin.site.register(CustomUser, CustomUserAdmin)