Fixed #24417 -- Added ModelAdmin.get_list_select_related()

django/contrib/admin/options.py

@@ -855,6 +855,13 @@ class ModelAdmin(BaseModelAdmin):
         """
         return self.list_filter
 
+    def get_list_select_related(self, request):
+        """
+        Returns a list of fields to add to the select_related() part of the
+        changelist items query.
+        """
+        return self.list_select_related
+
     def get_search_fields(self, request):
         """
         Returns a sequence containing the fields to be searched whenever
@@ -1433,6 +1440,7 @@ class ModelAdmin(BaseModelAdmin):
         list_display_links = self.get_list_display_links(request, list_display)
         list_filter = self.get_list_filter(request)
         search_fields = self.get_search_fields(request)
+        list_select_related = self.get_list_select_related(request)
 
         # Check actions to see if any are available on this changelist
         actions = self.get_actions(request)
@@ -1444,7 +1452,7 @@ class ModelAdmin(BaseModelAdmin):
         try:
             cl = ChangeList(request, self.model, list_display,
                 list_display_links, list_filter, self.date_hierarchy,
-                search_fields, self.list_select_related, self.list_per_page,
+                search_fields, list_select_related, self.list_per_page,
                 self.list_max_show_all, self.list_editable, self)
 
         except IncorrectLookupParameters:

docs/ref/contrib/admin/index.txt

@@ -920,6 +920,9 @@ subclass::
 
     will call ``select_related('author', 'category')``.
 
+    If you need to specify a dynamic value based on the request, you can
+    implement a :meth:`~ModelAdmin.get_list_select_related` method.
+
 .. attribute:: ModelAdmin.ordering
 
     Set ``ordering`` to specify how lists of objects should be ordered in the
@@ -932,7 +935,6 @@ subclass::
     If you need to specify a dynamic order (for example depending on user or
     language) you can implement a :meth:`~ModelAdmin.get_ordering` method.
 
-
 .. attribute:: ModelAdmin.paginator
 
     The paginator class to be used for pagination. By default,
@@ -1366,6 +1368,14 @@ templates used by the :class:`ModelAdmin` views:
     to return the same kind of sequence type as for the
     :attr:`~ModelAdmin.list_filter` attribute.
 
+.. method:: ModelAdmin.get_list_select_related(request)
+
+    .. versionadded:: 1.9
+
+    The ``get_list_select_related`` method is given the ``HttpRequest`` and
+    should return a boolean or list as :attr:`ModelAdmin.list_select_related`
+    does.
+
 .. method:: ModelAdmin.get_search_fields(request)
 
     The ``get_search_fields`` method is given the ``HttpRequest`` and is expected

docs/releases/1.9.txt

@@ -43,6 +43,11 @@ Minor features
   the old URL still redirects to the new one for backwards compatibility, but
   it may be removed in a future version.
 
+* :meth:`ModelAdmin.get_list_select_related()
+  <django.contrib.admin.ModelAdmin.get_list_select_related>` was added to allow
+  changing the ``select_related()`` values used in the admin's changelist query
+  based on the request.
+
 :mod:`django.contrib.auth`
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
 

tests/admin_changelist/tests.py

@@ -50,9 +50,10 @@ class ChangeListTests(TestCase):
         """
         m = ChildAdmin(Child, admin.site)
         request = self.factory.get('/child/')
+        list_select_related = m.get_list_select_related(request)
         cl = ChangeList(request, Child, m.list_display, m.list_display_links,
                         m.list_filter, m.date_hierarchy, m.search_fields,
-                        m.list_select_related, m.list_per_page,
+                        list_select_related, m.list_per_page,
                         m.list_max_show_all, m.list_editable, m)
         self.assertEqual(cl.queryset.query.select_related, {
             'parent': {'name': {}}
@@ -61,9 +62,10 @@ class ChangeListTests(TestCase):
     def test_select_related_as_tuple(self):
         ia = InvitationAdmin(Invitation, admin.site)
         request = self.factory.get('/invitation/')
+        list_select_related = ia.get_list_select_related(request)
         cl = ChangeList(request, Child, ia.list_display, ia.list_display_links,
                         ia.list_filter, ia.date_hierarchy, ia.search_fields,
-                        ia.list_select_related, ia.list_per_page,
+                        list_select_related, ia.list_per_page,
                         ia.list_max_show_all, ia.list_editable, ia)
         self.assertEqual(cl.queryset.query.select_related, {'player': {}})
 
@@ -71,12 +73,29 @@ class ChangeListTests(TestCase):
         ia = InvitationAdmin(Invitation, admin.site)
         ia.list_select_related = ()
         request = self.factory.get('/invitation/')
+        list_select_related = ia.get_list_select_related(request)
         cl = ChangeList(request, Child, ia.list_display, ia.list_display_links,
                         ia.list_filter, ia.date_hierarchy, ia.search_fields,
-                        ia.list_select_related, ia.list_per_page,
+                        list_select_related, ia.list_per_page,
                         ia.list_max_show_all, ia.list_editable, ia)
         self.assertEqual(cl.queryset.query.select_related, False)
 
+    def test_get_select_related_custom_method(self):
+        class GetListSelectRelatedAdmin(admin.ModelAdmin):
+            list_display = ('band', 'player')
+
+            def get_list_select_related(self, request):
+                return ('band', 'player')
+
+        ia = GetListSelectRelatedAdmin(Invitation, admin.site)
+        request = self.factory.get('/invitation/')
+        list_select_related = ia.get_list_select_related(request)
+        cl = ChangeList(request, Child, ia.list_display, ia.list_display_links,
+                        ia.list_filter, ia.date_hierarchy, ia.search_fields,
+                        list_select_related, ia.list_per_page,
+                        ia.list_max_show_all, ia.list_editable, ia)
+        self.assertEqual(cl.queryset.query.select_related, {'player': {}, 'band': {}})
+
     def test_result_list_empty_changelist_value(self):
         """
         Regression test for #14982: EMPTY_CHANGELIST_VALUE should be honored