rewrite PasswordFactor to use backends setting instead of trying all backends

passbook/core/forms/factors.py

@@ -1,13 +1,20 @@
 """passbook administration forms"""
 from django import forms
+from django.conf import settings
 from django.contrib.admin.widgets import FilteredSelectMultiple
 from django.utils.translation import gettext as _
 
 from passbook.core.models import DummyFactor, PasswordFactor
-from passbook.lib.fields import DynamicArrayField
+from passbook.lib.utils.reflection import path_to_class
 
 GENERAL_FIELDS = ['name', 'slug', 'order', 'policies', 'enabled']
 
+def get_authentication_backends():
+    """Return all available authentication backends as tuple set"""
+    for backend in settings.AUTHENTICATION_BACKENDS:
+        klass = path_to_class(backend)
+        yield backend, getattr(klass(), 'name', '%s (%s)' % (klass.__name__, klass.__module__))
+
 class PasswordFactorForm(forms.ModelForm):
     """Form to create/edit Password Factors"""
 
@@ -18,10 +25,9 @@ class PasswordFactorForm(forms.ModelForm):
         widgets = {
             'name': forms.TextInput(),
             'order': forms.NumberInput(),
-            'policies': FilteredSelectMultiple(_('policies'), False)
-        }
-        field_classes = {
-            'backends': DynamicArrayField
+            'policies': FilteredSelectMultiple(_('policies'), False),
+            'backends': FilteredSelectMultiple(_('backends'), False,
+                                               choices=get_authentication_backends())
         }
 
 class DummyFactorForm(forms.ModelForm):