id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
28717	Document that using ModelAdmin.list_filter with foreign keys may require a database router	Adam Brenecki	nobody	"I'm using Django's admin on a model on one of a number of secondary databases. The model has {{{managed = False}}} and doesn't exist on the {{{default}}} database. I'm not using a custom database router; I've overridden methods on my {{{ModelAdmin}}} as per here: https://docs.djangoproject.com/en/1.11/topics/db/multi-db/#exposing-multiple-databases-in-django-s-admin-interface. This mostly works, except when I add a {{{ForeignKey}}} field to {{{list_filter}}}, when it appears to try to query the primary database for the values to display in the filter, and I can't find a way to override this behaviour in {{{ModelAdmin}}}.

This happens both on Django 1.11.5 and on master (as of commit 1b73ccc); other models that have {{{list_filter}}}s that aren't foreign keys work fine, as does this model if I comment out the line with {{{list_filter}}}.

Below is an excerpt from my {{{admin.py}}} as well as the full stack trace:

{{{#!python
from django.contrib import admin

from . import models


class ApplyOLModelAdmin(admin.ModelAdmin):
    def save_model(self, request, obj, form, change):
        obj.save(using=request.applyol)

    def delete_model(self, request, obj):
        obj.delete(using=request.applyol)

    def get_queryset(self, request):
        return super().get_queryset(request).using(request.applyol)

    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        return super().formfield_for_foreignkey(
            db_field, request, using=request.applyol, **kwargs
        )

    def formfield_for_manytomany(self, db_field, request, **kwargs):
        return super().formfield_for_manytomany(
            db_field, request, using=request.applyol, **kwargs
        )

    def has_module_permission(self, request):
        return True

    def has_add_permission(self, request, obj=None):
        return True

    def has_change_permission(self, request, obj=None):
        return True

    def has_delete_permission(self, request, obj=None):
        return True


@admin.register(models.CountryCity)
class CountryCityAdmin(ApplyOLModelAdmin):
    list_display = ('country', 'code', 'name')
    list_display_links = ('name',)
    list_filter = ('country',)
    ordering = ('country__name', 'name')
}}}

{{{
Environment:


Request Method: GET
Request URL: http://localhost:8000/dev/admin/applyol_editor/countrycity/

Django Version: 2.1.dev20171016175638
Python Version: 3.6.2
Installed Applications:
('sl_admin.apps.applyol_editor',
 'django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'form_utils',
 'webpack_loader',
 'widget_tweaks',
 'sl_admin.lib',
 'sl_admin.apps.accounts',
 'sl_admin.apps.landing',
 'sl_admin.apps.form_builder')
Installed Middleware:
('django.middleware.security.SecurityMiddleware',
 'whitenoise.middleware.WhiteNoiseMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware',
 'csp.middleware.CSPMiddleware',
 'sl_admin.lib.middleware.XUACompatibleMiddleware',
 'sl_admin.apps.accounts.middleware.SocialAuthErrorMiddleware',
 'sl_admin.lib.environment.EnvironmentMiddleware',
 'rollbar.contrib.django.middleware.RollbarNotifierMiddleware')



Traceback:

File ""/Users/adambrenecki/Projects/django/django/db/backends/utils.py"" in _execute
  86.                 return self.cursor.execute(sql, params)

The above exception (relation ""APPLYOL.TBLCOUNTRY"" does not exist
LINE 1: ...ODE"", ""APPLYOL"".""TBLCOUNTRY"".""ISNATIONALITY"" FROM ""APPLYOL""....
                                                             ^
) was the direct cause of the following exception:

File ""/Users/adambrenecki/Projects/django/django/core/handlers/exception.py"" in inner
  35.             response = get_response(request)

File ""/Users/adambrenecki/Projects/django/django/core/handlers/base.py"" in _get_response
  128.                 response = self.process_exception_by_middleware(e, request)

File ""/Users/adambrenecki/Projects/django/django/core/handlers/base.py"" in _get_response
  126.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/options.py"" in wrapper
  574.                 return self.admin_site.admin_view(view)(*args, **kwargs)

File ""/Users/adambrenecki/Projects/django/django/utils/decorators.py"" in _wrapped_view
  142.                     response = view_func(request, *args, **kwargs)

File ""/Users/adambrenecki/Projects/django/django/views/decorators/cache.py"" in _wrapped_view_func
  44.         response = view_func(request, *args, **kwargs)

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/sites.py"" in inner
  223.             return view(request, *args, **kwargs)

File ""/Users/adambrenecki/Projects/django/django/utils/decorators.py"" in _wrapper
  62.             return bound_func(*args, **kwargs)

File ""/Users/adambrenecki/Projects/django/django/utils/decorators.py"" in _wrapped_view
  142.                     response = view_func(request, *args, **kwargs)

File ""/Users/adambrenecki/Projects/django/django/utils/decorators.py"" in bound_func
  58.                 return func.__get__(self, type(self))(*args2, **kwargs2)

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/options.py"" in changelist_view
  1570.             cl = self.get_changelist_instance(request)

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/options.py"" in get_changelist_instance
  705.             self,

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/views/main.py"" in __init__
  75.         self.queryset = self.get_queryset(request)

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/views/main.py"" in get_queryset
  313.          filters_use_distinct) = self.get_filters(request)

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/views/main.py"" in get_filters
  129.                         self.model, self.model_admin, field_path=field_path

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/filters.py"" in create
  157.             return list_filter_class(field, request, params, model, model_admin, field_path=field_path)

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/filters.py"" in __init__
  168.         self.lookup_choices = self.field_choices(field, request, model_admin)

File ""/Users/adambrenecki/Projects/django/django/contrib/admin/filters.py"" in field_choices
  195.         return field.get_choices(include_blank=False)

File ""/Users/adambrenecki/Projects/django/django/db/models/fields/__init__.py"" in get_choices
  812.                        limit_choices_to)]

File ""/Users/adambrenecki/Projects/django/django/db/models/query.py"" in __iter__
  270.         self._fetch_all()

File ""/Users/adambrenecki/Projects/django/django/db/models/query.py"" in _fetch_all
  1174.             self._result_cache = list(self._iterable_class(self))

File ""/Users/adambrenecki/Projects/django/django/db/models/query.py"" in __iter__
  55.         results = compiler.execute_sql(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size)

File ""/Users/adambrenecki/Projects/django/django/db/models/sql/compiler.py"" in execute_sql
  1043.             cursor.execute(sql, params)

File ""/Users/adambrenecki/Projects/django/django/db/backends/utils.py"" in execute
  101.             return super().execute(sql, params)

File ""/Users/adambrenecki/Projects/django/django/db/backends/utils.py"" in execute
  69.         return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)

File ""/Users/adambrenecki/Projects/django/django/db/backends/utils.py"" in _execute_with_wrappers
  78.         return executor(sql, params, many, context)

File ""/Users/adambrenecki/Projects/django/django/db/backends/utils.py"" in _execute
  86.                 return self.cursor.execute(sql, params)

File ""/Users/adambrenecki/Projects/django/django/db/utils.py"" in __exit__
  89.                 raise dj_exc_value.with_traceback(traceback) from exc_value

File ""/Users/adambrenecki/Projects/django/django/db/backends/utils.py"" in _execute
  86.                 return self.cursor.execute(sql, params)

Exception Type: ProgrammingError at /dev/admin/applyol_editor/countrycity/
Exception Value: relation ""APPLYOL.TBLCOUNTRY"" does not exist
LINE 1: ...ODE"", ""APPLYOL"".""TBLCOUNTRY"".""ISNATIONALITY"" FROM ""APPLYOL""....
                                                             ^
}}}"	Cleanup/optimization	closed	Documentation	1.11	Normal	wontfix			Accepted	0	0	0	0	0	0