From d599052a159454e33c44d9786f36189285d6c8ca Mon Sep 17 00:00:00 2001
From: Adrian Holovaty <adrian@holovaty.com>
Date: Fri, 16 Jun 2006 19:42:06 +0000
Subject: [PATCH] Added AllValuesFilterSpec to admin changelist filters, which
 lets you put any arbitrary field in Admin.list_filter. To determine the list
 of all available choices, Django does a SELECT DISTINCT. Note this is
 backwards-incompatible for people who have defined and registered their own
 FilterSpecs, because each FilterSpec now takes a 'model' parameter.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@3136 bcc190cf-cafb-0310-a4f2-bffc1f526a37
---
 django/contrib/admin/filterspecs.py | 59 ++++++++++++++++++++---------
 django/contrib/admin/views/main.py  |  2 +-
 2 files changed, 42 insertions(+), 19 deletions(-)

diff --git a/django/contrib/admin/filterspecs.py b/django/contrib/admin/filterspecs.py
index 0284f13114..25376be12a 100644
--- a/django/contrib/admin/filterspecs.py
+++ b/django/contrib/admin/filterspecs.py
@@ -11,18 +11,18 @@ import datetime
 
 class FilterSpec(object):
     filter_specs = []
-    def __init__(self, f, request, params):
+    def __init__(self, f, request, params, model):
         self.field = f
         self.params = params
 
     def register(cls, test, factory):
-        cls.filter_specs.append( (test, factory) )
+        cls.filter_specs.append((test, factory))
     register = classmethod(register)
 
-    def create(cls, f, request, params):
+    def create(cls, f, request, params, model):
         for test, factory in cls.filter_specs:
             if test(f):
-                return factory(f, request, params)
+                return factory(f, request, params, model)
     create = classmethod(create)
 
     def has_output(self):
@@ -48,8 +48,8 @@ class FilterSpec(object):
         return "".join(t)
 
 class RelatedFilterSpec(FilterSpec):
-    def __init__(self, f, request, params):
-        super(RelatedFilterSpec, self).__init__(f, request, params)
+    def __init__(self, f, request, params, model):
+        super(RelatedFilterSpec, self).__init__(f, request, params, model)
         if isinstance(f, models.ManyToManyField):
             self.lookup_title = f.rel.to._meta.verbose_name
         else:
@@ -71,31 +71,31 @@ class RelatedFilterSpec(FilterSpec):
         for val in self.lookup_choices:
             pk_val = getattr(val, self.field.rel.to._meta.pk.attname)
             yield {'selected': self.lookup_val == str(pk_val),
-                   'query_string': cl.get_query_string( {self.lookup_kwarg: pk_val}),
+                   'query_string': cl.get_query_string({self.lookup_kwarg: pk_val}),
                    'display': val}
 
 FilterSpec.register(lambda f: bool(f.rel), RelatedFilterSpec)
 
 class ChoicesFilterSpec(FilterSpec):
-    def __init__(self, f, request, params):
-        super(ChoicesFilterSpec, self).__init__(f, request, params)
+    def __init__(self, f, request, params, model):
+        super(ChoicesFilterSpec, self).__init__(f, request, params, model)
         self.lookup_kwarg = '%s__exact' % f.name
         self.lookup_val = request.GET.get(self.lookup_kwarg, None)
 
     def choices(self, cl):
         yield {'selected': self.lookup_val is None,
-               'query_string': cl.get_query_string( {}, [self.lookup_kwarg]),
+               'query_string': cl.get_query_string({}, [self.lookup_kwarg]),
                'display': _('All')}
         for k, v in self.field.choices:
             yield {'selected': str(k) == self.lookup_val,
-                    'query_string': cl.get_query_string( {self.lookup_kwarg: k}),
+                    'query_string': cl.get_query_string({self.lookup_kwarg: k}),
                     'display': v}
 
 FilterSpec.register(lambda f: bool(f.choices), ChoicesFilterSpec)
 
 class DateFieldFilterSpec(FilterSpec):
-    def __init__(self, f, request, params):
-        super(DateFieldFilterSpec, self).__init__(f, request, params)
+    def __init__(self, f, request, params, model):
+        super(DateFieldFilterSpec, self).__init__(f, request, params, model)
 
         self.field_generic = '%s__' % self.field.name
 
@@ -123,14 +123,14 @@ class DateFieldFilterSpec(FilterSpec):
     def choices(self, cl):
         for title, param_dict in self.links:
             yield {'selected': self.date_params == param_dict,
-                   'query_string': cl.get_query_string( param_dict, self.field_generic),
+                   'query_string': cl.get_query_string(param_dict, self.field_generic),
                    'display': title}
 
 FilterSpec.register(lambda f: isinstance(f, models.DateField), DateFieldFilterSpec)
 
 class BooleanFieldFilterSpec(FilterSpec):
-    def __init__(self, f, request, params):
-        super(BooleanFieldFilterSpec, self).__init__(f, request, params)
+    def __init__(self, f, request, params, model):
+        super(BooleanFieldFilterSpec, self).__init__(f, request, params, model)
         self.lookup_kwarg = '%s__exact' % f.name
         self.lookup_kwarg2 = '%s__isnull' % f.name
         self.lookup_val = request.GET.get(self.lookup_kwarg, None)
@@ -142,11 +142,34 @@ class BooleanFieldFilterSpec(FilterSpec):
     def choices(self, cl):
         for k, v in ((_('All'), None), (_('Yes'), '1'), (_('No'), '0')):
             yield {'selected': self.lookup_val == v and not self.lookup_val2,
-                   'query_string': cl.get_query_string( {self.lookup_kwarg: v}, [self.lookup_kwarg2]),
+                   'query_string': cl.get_query_string({self.lookup_kwarg: v}, [self.lookup_kwarg2]),
                    'display': k}
         if isinstance(self.field, models.NullBooleanField):
             yield {'selected': self.lookup_val2 == 'True',
-                   'query_string': cl.get_query_string( {self.lookup_kwarg2: 'True'}, [self.lookup_kwarg]),
+                   'query_string': cl.get_query_string({self.lookup_kwarg2: 'True'}, [self.lookup_kwarg]),
                    'display': _('Unknown')}
 
 FilterSpec.register(lambda f: isinstance(f, models.BooleanField) or isinstance(f, models.NullBooleanField), BooleanFieldFilterSpec)
+
+# This should be registered last, because it's a last resort. For example,
+# if a field is eligible to use the BooleanFieldFilterSpec, that'd be much
+# more appropriate, and the AllValuesFilterSpec won't get used for it.
+class AllValuesFilterSpec(FilterSpec):
+    def __init__(self, f, request, params, model):
+        super(AllValuesFilterSpec, self).__init__(f, request, params, model)
+        self.lookup_val = request.GET.get(f.name, None)
+        self.lookup_choices = model._meta.admin.manager.distinct().order_by(f.name).values(f.name)
+
+    def title(self):
+        return self.field.verbose_name
+
+    def choices(self, cl):
+        yield {'selected': self.lookup_val is None,
+               'query_string': cl.get_query_string({}, [self.field.name]),
+               'display': _('All')}
+        for val in self.lookup_choices:
+            val = str(val[self.field.name])
+            yield {'selected': self.lookup_val == val,
+                   'query_string': cl.get_query_string({self.field.name: val}),
+                   'display': val}
+FilterSpec.register(lambda f: True, AllValuesFilterSpec)
diff --git a/django/contrib/admin/views/main.py b/django/contrib/admin/views/main.py
index af55587d23..ea7aeb490b 100644
--- a/django/contrib/admin/views/main.py
+++ b/django/contrib/admin/views/main.py
@@ -574,7 +574,7 @@ class ChangeList(object):
             filter_fields = [self.lookup_opts.get_field(field_name) \
                               for field_name in self.lookup_opts.admin.list_filter]
             for f in filter_fields:
-                spec = FilterSpec.create(f, request, self.params)
+                spec = FilterSpec.create(f, request, self.params, self.model)
                 if spec and spec.has_output():
                     filter_specs.append(spec)
         return filter_specs, bool(filter_specs)