From d3c80b9d34a063a1fe50c9fe2cd708bbb232848c Mon Sep 17 00:00:00 2001
From: Diogo Machado <diogo.laginha.machado@gmail.com>
Date: Mon, 16 Mar 2015 21:54:20 +0000
Subject: [PATCH] group filter fields with meta option 'together'

---
 AUTHORS                     |  3 ++-
 django_filters/filterset.py | 20 ++++++++++++++++++
 docs/usage.txt              | 18 ++++++++++++++++
 setup.py                    |  2 +-
 tests/test_filterset.py     | 42 +++++++++++++++++++++++++++++++++++++
 5 files changed, 83 insertions(+), 2 deletions(-)

diff --git a/AUTHORS b/AUTHORS
index b16752a..6ef5337 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -18,4 +18,5 @@ Vladimir Sidorenko
 Tom Christie
 Remco Wendt
 Axel Haustant
-Brad Erickson
\ No newline at end of file
+Brad Erickson
+Diogo Laginha
\ No newline at end of file
diff --git a/django_filters/filterset.py b/django_filters/filterset.py
index 64285be..60d020b 100644
--- a/django_filters/filterset.py
+++ b/django_filters/filterset.py
@@ -141,6 +141,8 @@ class FilterSetOptions(object):
         self.order_by = getattr(options, 'order_by', False)
 
         self.form = getattr(options, 'form', forms.Form)
+        
+        self.together = getattr(options, 'together', None)
 
 
 class FilterSetMetaclass(type):
@@ -352,6 +354,22 @@ class BaseFilterSet(object):
 
     @property
     def form(self):
+        
+        def full_clean(form):
+            super(form.__class__, form).full_clean()
+            message = 'Following fields must be together: %s'
+            together = self._meta.together
+            cleaned_data = form.cleaned_data
+            if isinstance(together[0], (list, tuple)):
+                for each in together:
+                    count = len([i for i in each if cleaned_data.get(i)])
+                    if 0 < count < len(each):
+                        return form.add_error(None, message % ','.join(each))
+            else:
+                count = len([i for i in together if cleaned_data.get(i)])
+                if 0 < count < len(together):
+                    return form.add_error(None, message % ','.join(together))
+
         if not hasattr(self, '_form'):
             fields = OrderedDict([
                 (name, filter_.field)
@@ -359,6 +377,8 @@ class BaseFilterSet(object):
             fields[self.order_by_field] = self.ordering_field
             Form = type(str('%sForm' % self.__class__.__name__),
                         (self._meta.form,), fields)
+            if self._meta.together:
+                Form.full_clean = full_clean
             if self.is_bound:
                 self._form = Form(self.data, prefix=self.form_prefix)
             else:
diff --git a/docs/usage.txt b/docs/usage.txt
index 3a35fff..5b37df8 100644
--- a/docs/usage.txt
+++ b/docs/usage.txt
@@ -199,6 +199,24 @@ The inner ``Meta`` class also takes an optional ``form`` argument.  This is a
 form class from which ``FilterSet.form`` will subclass.  This works similar to
 the ``form`` option on a ``ModelAdmin.``
 
+Group fields with ``together``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The inner ``Meta`` class also takes an optional ``together`` argument.  This 
+is a list of lists, each containing field names. For convenience can be a 
+single list/tuple when dealing with a single set of fields. Fields within a 
+field set must either be all or none present in the request for 
+``FilterSet.form`` to be valid.
+
+    import django_filters
+
+    class ProductFilter(django_filters.FilterSet):
+        class Meta:
+            model = Product
+            fields = ['price', 'release_date', 'rating']
+            together = ['rating', 'price']
+
+
 Non-Meta options
 ----------------
 
diff --git a/setup.py b/setup.py
index 1e55b33..e120cc2 100644
--- a/setup.py
+++ b/setup.py
@@ -16,7 +16,7 @@ if sys.argv[-1] == 'publish':
 
 setup(
     name='django-filter',
-    version='0.9.2',
+    version='0.9.3',
     description=('Django-filter is a reusable Django application for allowing'
                  ' users to filter querysets dynamically.'),
     long_description=readme,
diff --git a/tests/test_filterset.py b/tests/test_filterset.py
index e0256cd..8a9ca1c 100644
--- a/tests/test_filterset.py
+++ b/tests/test_filterset.py
@@ -628,3 +628,45 @@ class FilterSetOrderingTests(TestCase):
         f = F({'o': 'status'}, queryset=self.qs)
         self.assertQuerysetEqual(
             f.qs, ['carl', 'alex', 'aaron', 'jacob'], lambda o: o.username)
+
+
+
+class FilterSetTogetherTests(TestCase):
+
+    def setUp(self):
+        self.alex = User.objects.create(username='alex', status=1)
+        self.jacob = User.objects.create(username='jacob', status=2)
+        self.qs = User.objects.all().order_by('id')
+    
+    def test_fields_set(self):
+        class F(FilterSet):
+            class Meta:
+                model = User
+                fields = ['username', 'status', 'is_active', 'first_name']
+                together = [
+                    ('username', 'status'), 
+                    ('first_name', 'is_active'),
+                ]
+
+        f = F({}, queryset=self.qs)
+        self.assertEqual(f.qs.count(), 2)
+        f = F({'username': 'alex'}, queryset=self.qs)
+        self.assertEqual(f.qs.count(), 0)
+        f = F({'username': 'alex', 'status': 1}, queryset=self.qs)
+        self.assertEqual(f.qs.count(), 1)
+        self.assertQuerysetEqual(f.qs, [self.alex.pk], lambda o: o.pk)
+        
+    def test_single_fields_set(self):
+        class F(FilterSet):
+            class Meta:
+                model = User
+                fields = ['username', 'status']
+                together = ['username', 'status']
+        
+        f = F({}, queryset=self.qs)
+        self.assertEqual(f.qs.count(), 2)
+        f = F({'username': 'alex'}, queryset=self.qs)
+        self.assertEqual(f.qs.count(), 0)
+        f = F({'username': 'alex', 'status': 1}, queryset=self.qs)
+        self.assertEqual(f.qs.count(), 1)
+        self.assertQuerysetEqual(f.qs, [self.alex.pk], lambda o: o.pk)