[fix/feature] Fix autocomplete filter

[fix] Fixed "None" option of AutocompleteFilter
AutocompleteFilter shows "None" option only if the field is
nullable.

[feature] Added setting to make AutocompleteFilter view configurable
Added "OPENWISP_AUTOCOMPLETE_FILTER_VIEW" project setting to allow
configuring the view.

[fix] Don't show null option on reverse relation

README.rst

@@ -1811,6 +1811,17 @@ Sets the soft time limit for celery tasks using
 Sets the hard time limit for celery tasks using
 `OpenwispCeleryTask <#openwisp_utilstasksopenwispcelerytask>`_.
 
+``OPENWISP_AUTOCOMPLETE_FILTER_VIEW``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
++---------+-------------------------------------------------------------+
+| type    | ``str``                                                     |
++---------+-------------------------------------------------------------+
+| default | ``'openwisp_utils.admin_theme.views.AutocompleteJsonView'`` |
++---------+-------------------------------------------------------------+
+
+Dotted path to the ``AutocompleteJsonView`` used by the
+``openwisp_utils.admin_theme.filters.AutocompleteFilter``.
+
 Installing for development
 --------------------------
 

openwisp_utils/admin_theme/admin.py

@@ -3,11 +3,11 @@
 from django.conf import settings
 from django.contrib import admin
 from django.urls import path
+from django.utils.module_loading import import_string
 from django.utils.translation import gettext_lazy
 
 from . import settings as app_settings
 from .dashboard import get_dashboard_context
-from .views import AutocompleteJsonView
 
 logger = logging.getLogger(__name__)
 
@@ -31,10 +31,11 @@ def index(self, request, extra_context=None):
         return super().index(request, extra_context=context)
 
     def get_urls(self):
+        autocomplete_view = import_string(app_settings.AUTOCOMPLETE_FILTER_VIEW)
         return [
             path(
                 'ow-auto-filter/',
-                self.admin_view(AutocompleteJsonView.as_view(admin_site=self)),
+                self.admin_view(autocomplete_view.as_view(admin_site=self)),
                 name='ow-auto-filter',
             ),
         ] + super().get_urls()

openwisp_utils/admin_theme/settings.py

@@ -24,3 +24,8 @@
 )
 
 OPENWISP_HTML_EMAIL = getattr(settings, 'OPENWISP_HTML_EMAIL', True)
+AUTOCOMPLETE_FILTER_VIEW = getattr(
+    settings,
+    'OPENWISP_AUTOCOMPLETE_FILTER_VIEW',
+    'openwisp_utils.admin_theme.views.AutocompleteJsonView',
+)

openwisp_utils/admin_theme/templates/admin/auto_filter.html

@@ -1,5 +1,5 @@
 {% load i18n %}
-<div class="auto-filter ow-filter">
+<div class="ow-filter auto-filter">
   {% include 'django-admin-autocomplete-filter/autocomplete-filter.html' %}
   <div class="auto-filter-choices"></div>
 </div>

openwisp_utils/admin_theme/views.py

@@ -22,7 +22,12 @@ def get(self, request, *args, **kwargs):
         context = self.get_context_data()
         # Add option for filtering objects with None field.
         results = []
-        if not self.term or self.term == '-':
+        if (
+            getattr(self.source_field, 'null', False)
+            and not getattr(self.source_field, '_get_limit_choices_to_mocked', False)
+            and not self.term
+            or self.term == '-'
+        ):
             results += [{'id': 'null', 'text': '-'}]
         results += [
             {'id': str(obj.pk), 'text': self.display_text(obj)}
@@ -37,6 +42,7 @@ def get(self, request, *args, **kwargs):
 
     def support_reverse_relation(self):
         if not hasattr(self.source_field, 'get_limit_choices_to'):
+            self.source_field._get_limit_choices_to_mocked = True
 
             def get_choices_mock():
                 return {}

tests/test_project/admin.py

@@ -37,6 +37,7 @@ class UserAdmin(admin.ModelAdmin):
         'is_superuser',
         'is_active',
     ]
+    search_fields = ('username',)
 
 
 @admin.register(Book)
@@ -95,14 +96,20 @@ class ReverseBookFilter(AutocompleteFilter):
     parameter_name = 'book'
 
 
+class AutoOwnerFilter(AutocompleteFilter):
+    title = _('owner')
+    field_name = 'owner'
+    parameter_name = 'owner_id'
+
+
 @admin.register(Shelf)
 class ShelfAdmin(TimeReadonlyAdminMixin, admin.ModelAdmin):
     # DO NOT CHANGE: used for testing filters
     list_filter = [
         ShelfFilter,
         ['books_type', InputFilter],
         ['id', InputFilter],
-        'owner__username',
+        AutoOwnerFilter,
         'books_type',
         ReverseBookFilter,
     ]

tests/test_project/tests/test_admin.py

@@ -412,6 +412,7 @@ def test_input_filter(self):
 
     def test_ow_auto_filter_view(self):
         url = reverse('admin:ow-auto-filter')
+        url = f'{url}?app_label=test_project&model_name=shelf&field_name=book'
         user = User.objects.create(
             username='operator',
             password='pass',

tests/test_project/tests/test_selenium.py

@@ -500,13 +500,22 @@ def test_shelf_filter(self):
         with self.subTest('Test multiple filters'):
             # Select Fantasy book type
             books_type_title = self._get_filter_title('type-of-book')
-            username_title = self._get_filter_title('username')
+            owner_filter_xpath = '//*[@id="select2-id-owner_id-dal-filter-container"]'
+            owner_filter_option_xpath = (
+                '//*[@id="select2-id-owner_id-dal-filter-results"]/li[4]'
+            )
+            owner_filter = self.web_driver.find_element_by_xpath(owner_filter_xpath)
             books_type_title.click()
             fantasy_option = self._get_filter_anchor('books_type__exact=FANTASY')
             fantasy_option.click()
-            username_title.click()
-            username_option = self._get_filter_anchor('owner__username=tester2')
-            username_option.click()
+            owner_filter.click()
+            WebDriverWait(self.web_driver, 2).until(
+                EC.visibility_of_element_located((By.XPATH, owner_filter_option_xpath))
+            )
+            owner_option = self.web_driver.find_element_by_xpath(
+                owner_filter_option_xpath
+            )
+            owner_option.click()
             filter_button = self._get_filter_button()
             filter_button.click()
             WebDriverWait(self.web_driver, 2).until(
@@ -690,7 +699,7 @@ def setUp(self):
         self.admin = self._create_admin()
         self.login()
 
-    def test_auto_complete_filter(self):
+    def test_autocomplete_shelf_filter(self):
         url = reverse('admin:test_project_book_changelist')
         user = self._create_user()
         horror_shelf = self._create_shelf(
@@ -703,8 +712,8 @@ def test_auto_complete_filter(self):
         book2 = self._create_book(name='Book 2', shelf=factual_shelf)
         select_id = 'id-shelf__id-dal-filter'
         filter_css_selector = f'#select2-{select_id}-container'
-        filter_null_option_xpath = f'//*[@id="select2-{select_id}-results"]/li[1]'
-        filter_option_xpath = f'//*[@id="select2-{select_id}-results"]/li[3]'
+        filter_options = f'//*[@id="select2-{select_id}-results"]/li'
+        filter_option_xpath = f'//*[@id="select2-{select_id}-results"]/li[2]'
 
         result_xpath = '//*[@id="result_list"]/tbody/tr/th/a[contains(text(), "{}")]'
         self.open(url)
@@ -726,14 +735,47 @@ def test_auto_complete_filter(self):
             self.web_driver.find_element_by_xpath(result_xpath.format(book1.name))
         # Book 2 is present
         self.web_driver.find_element_by_xpath(result_xpath.format(book2.name))
-        # Test null filter
+        # "shelf" field is not nullable, therefore none option should be absent
         self.web_driver.find_element_by_css_selector(filter_css_selector).click()
         self.web_driver.find_element_by_css_selector('.select2-container--open')
+        for option in self.web_driver.find_elements_by_xpath(filter_options):
+            self.assertNotEqual(option.text, '-')
+
+    def test_autocomplete_owner_filter(self):
+        """
+        Tests the null option of the AutocompleteFilter
+        """
+        url = reverse('admin:test_project_shelf_changelist')
+        user = self._create_user()
+        horror_shelf = self._create_shelf(
+            name='Horror', books_type='HORROR', owner=self.admin
+        )
+        factual_shelf = self._create_shelf(
+            name='Factual', books_type='FACTUAL', owner=user
+        )
+        select_id = 'id-owner_id-dal-filter'
+        filter_css_selector = f'#select2-{select_id}-container'
+        filter_null_option_xpath = f'//*[@id="select2-{select_id}-results"]/li[1]'
+        result_xpath = '//*[@id="result_list"]/tbody/tr/th/a[contains(text(), "{}")]'
+        self.open(url)
+        self.assertIn(
+            f'<select name="owner_id" id="{select_id}" class="admin-autocomplete',
+            self.web_driver.page_source,
+        )
+        self.web_driver.find_element_by_css_selector(filter_css_selector).click()
+        self.web_driver.find_element_by_css_selector('.select2-container--open')
+        self.assertIn(self.admin.username, self.web_driver.page_source)
+        self.assertIn(user.username, self.web_driver.page_source)
         self.web_driver.find_element_by_xpath(filter_null_option_xpath).click()
-        self.assertIn('shelf__id__isnull=true', self.web_driver.current_url)
+        self._get_filter_button().click()
+        self.assertIn('owner_id__isnull=true', self.web_driver.current_url)
         with self.assertRaises(NoSuchElementException):
-            # Book 1 is absent
-            self.web_driver.find_element_by_xpath(result_xpath.format(book1.name))
+            # horror_shelf is absent
+            self.web_driver.find_element_by_xpath(
+                result_xpath.format(horror_shelf.name)
+            )
         with self.assertRaises(NoSuchElementException):
-            # Book 2 is absent
-            self.web_driver.find_element_by_xpath(result_xpath.format(book2.name))
+            # factual_shelf absent
+            self.web_driver.find_element_by_xpath(
+                result_xpath.format(factual_shelf.name)
+            )