add integration with django-autocomplete-light

README.rst

@@ -72,13 +72,51 @@ The following apps are optional but will enhance the user experience:
 
 * The 'login su' form will render using `django-form-admin`_
 * The user selection widget will render using `django-ajax-selects`_
+* The user selection widget will render using `django-autocomplete-light`_
+
+`django-autocomplete-light`_ and `django-ajax-selects`_ are mutually exclusive.
 
 Note that `django-ajax-selects`_ requires the following settings:
 
 .. code-block:: python
 
     AJAX_LOOKUP_CHANNELS = {'django_su':  dict(model='auth.user', search_field='username')}
 
+`django-autocomplete-light`_ requires the following configuration:
+
+.. code-block:: python
+
+    # settings.py
+    # this setting will be used to find the named url for the autocomplete view
+    SU_DAL_VIEW_NAME = 'user-autocomplete'
+
+    # views.py
+    # we need an autocomplete view
+    from dal import autocomplete
+    from django.contrib.auth.models import User
+
+    class UserAutoComplete(autocomplete.Select2QuerySetView):
+      def get_queryset(self):
+        user = self.request.user
+        qs = User.objects.none()
+        if user.is_authenticated and user.is_staff:
+          qs = User.objects.filter(username__icontains=self.q)
+
+        return qs.order_by('pk')
+
+    # urls.py
+    from .views import UserAutoComplete
+    from django.conf.urls import url
+    from django.conf import settings
+
+    urlpatterns = [
+      #...
+      url(r'^user-autocomplete/$',
+          UserAutoComplete.as_view(),
+          name=settings.SU_DAL_VIEW_NAME
+      )
+      #....
+    ]
 
 Configuration (optional)
 ------------------------
@@ -174,4 +212,5 @@ django-su is packaged using seed_.
 
 .. _django-form-admin: http://pypi.python.org/pypi/django-form-admin
 .. _django-ajax-selects: http://pypi.python.org/pypi/django-ajax-selects
+.. _django-autocomplete-light: https://pypi.org/project/django-autocomplete-light/
 .. _seed: https://github.com/adamcharnock/seed/

django_su/forms.py

@@ -53,3 +53,24 @@ def __str__(self):
             except ImportError:
                 pass
         return super(UserSuForm, self).__str__()
+
+
+class UserSuDalForm(UserSuForm):
+    def __init__(self, *args, **kwargs):
+        super(UserSuForm, self).__init__(*args, **kwargs)
+
+        if {"dal", "dal_select2"}.issubset(settings.INSTALLED_APPS) and getattr(
+            settings, "SU_DAL_VIEW_NAME", None
+        ):
+            try:
+                from dal import autocomplete
+            except ImportError:
+                return
+            old_field = self.fields["user"]
+
+            self.fields["user"] = forms.ModelChoiceField(
+                required=old_field.required,
+                label=old_field.label,
+                queryset=old_field.queryset,
+                widget=autocomplete.ModelSelect2(url=settings.SU_DAL_VIEW_NAME),
+            )

django_su/tests/test_forms.py

@@ -0,0 +1,30 @@
+from dal import autocomplete
+from django.contrib.auth import get_user_model
+from django.forms import widgets
+from django.test import TestCase, override_settings
+
+from django_su.forms import UserSuDalForm
+
+
+User = get_user_model()
+
+
+class TestSuForms(TestCase):
+    def setUp(self):
+        super(TestSuForms, self).setUp()
+
+        user = User.objects.create(username="user")
+        user.set_password("pass")
+        user.save()
+        self.user = user
+
+    @override_settings(SU_DAL_VIEW_NAME="sampleview")
+    def test_dal_form_use_autocomplete_widget(self):
+        """Ensure form uses autocomplete widget when SU_DAL_VIEW_NAME is present"""
+        form = UserSuDalForm(data={"user": self.user})
+        self.assertIsInstance(form.fields["user"].widget, autocomplete.ModelSelect2)
+
+    def test_dal_form_use_default_widget_if_dal_view_not_set(self):
+        """Ensure form uses default widget when SU_DAL_VIEW_NAME is not present"""
+        form = UserSuDalForm(data={"user": self.user})
+        self.assertIsInstance(form.fields["user"].widget, widgets.Select)

django_su/tests/test_views.py

@@ -1,10 +1,11 @@
 from datetime import date, timezone
+from unittest import mock
 
 from django.conf import settings
 from django.contrib import auth
 from django.contrib.auth import get_user_model
 from django.contrib.sessions.backends import cached_db
-from django.test import Client, TestCase
+from django.test import Client, TestCase, override_settings
 from django.urls import reverse
 from django.utils.datetime_safe import datetime
 
@@ -197,6 +198,18 @@ def test_post_invalid(self):
             str(self.client.session[auth.SESSION_KEY]), str(self.authorized_user.id)
         )
 
+    @override_settings(SU_DAL_VIEW_NAME="sampleview")
+    def test_uses_autocomplete_form(self):
+        """Ensure the view uses the correct form instance when SU_DAL_VIEW_NAME is present"""
+        self.client.login(username="authorized", password="pass")
+
+        with mock.patch("django_su.views.UserSuDalForm") as dal_form:
+            dal_form.return_value.is_valid.return_value = False
+            response = self.client.get(reverse("su_login"))
+
+        dal_form.assert_called_once()
+        self.assertEqual(response.status_code, 200)
+
 
 class LogoutViewTestCase(SuViewsBaseTestCase):
     def test_valid_get(self):

django_su/views.py

@@ -16,7 +16,7 @@
 from django.views.decorators.csrf import csrf_protect
 from django.views.decorators.http import require_http_methods
 
-from .forms import UserSuForm
+from .forms import UserSuDalForm, UserSuForm
 from .utils import custom_login_action, su_login_callback
 
 
@@ -61,7 +61,13 @@ def login_as_user(request, user_id):
 @csrf_protect
 @require_http_methods(["POST", "GET"])
 @user_passes_test(su_login_callback)
-def su_login(request, form_class=UserSuForm, template_name="su/login.html"):
+def su_login(request, form_class=None, template_name="su/login.html"):
+    if form_class is None:
+        if getattr(settings, "SU_DAL_VIEW_NAME", None):
+            form_class = UserSuDalForm
+        else:
+            form_class = UserSuForm
+
     form = form_class(request.POST or None)
     if form.is_valid():
         return login_as_user(request, form.get_user().pk)

example/settings.py

@@ -85,6 +85,8 @@
     # 'guardian',
     "formadmin",  # pip install django-form-admin
     "ajax_select",  # pip install django-ajax-selects
+    "dal",  # pip install django-autocomplete-light
+    "dal_select2",  # pip install django-autocomplete-light
 ]
 
 INSTALLED_APPS = PROJECT_APPS + INSTALLED_APPS

requirements.test.txt

@@ -1,3 +1,4 @@
 coveralls
 django-form-admin
 django-ajax-selects
+django-autocomplete-light