[PATCH 6/6] REST: Resolve issues with filters

[Stephen Finucane]

Turns out filtering patches using a series string wasn't as easy as we
thought. We need to slugify State.name, but unfortunately that isn't
stored in the database. The tests were hiding this fact as State objects
created by 'tests.utils.create_state' don't have spaces in them.

Override custom versions of both django-filter's 'Filter' class and
the Django 'Form' required by this, and update the tests to prevent a
regression.

Signed-off-by: Stephen Finucane <stephen at that.guru>
Fixes: 6222574 ("REST: filter patches by state name")
Cc: Philippe Pepiot <philippe.pepiot at logilab.fr>
---
 patchwork/api/filters.py         | 36 +++++++++++++++++++++++++++++++-----
 patchwork/api/patch.py           |  2 +-
 patchwork/models.py              |  4 ++++
 patchwork/tests/test_rest_api.py | 10 +++++-----
 4 files changed, 41 insertions(+), 11 deletions(-)

diff --git a/patchwork/api/filters.py b/patchwork/api/filters.py
index 12a54a8..00efc99 100644
--- a/patchwork/api/filters.py
+++ b/patchwork/api/filters.py
@@ -17,10 +17,11 @@
 # along with Patchwork; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 
+from django.core.exceptions import ValidationError
 from django_filters import FilterSet
 from django_filters import IsoDateTimeFilter
-from django_filters import CharFilter
 from django_filters import ModelChoiceFilter
+from django.forms import ModelChoiceField
 
 from patchwork.compat import LOOKUP_FIELD
 from patchwork.models import Bundle
@@ -30,6 +31,7 @@ from patchwork.models import Event
 from patchwork.models import Patch
 from patchwork.models import Project
 from patchwork.models import Series
+from patchwork.models import State
 
 
 class TimestampMixin(FilterSet):
@@ -59,15 +61,39 @@ class CoverLetterFilter(ProjectMixin, TimestampMixin, FilterSet):
         fields = ('project', 'series', 'submitter')
 
 
+class StateChoiceField(ModelChoiceField):
+
+    def prepare_value(self, value):
+        if hasattr(value, '_meta'):
+            return value.slug
+        else:
+            return super(StateChoiceField, self).prepare_value(value)
+
+    def to_python(self, value):
+        if value in self.empty_values:
+            return None
+        try:
+            value = ' '.join(value.split('-'))
+            value = self.queryset.get(name__iexact=value)
+        except (ValueError, TypeError, self.queryset.model.DoesNotExist):
+            raise ValidationError(self.error_messages['invalid_choice'],
+                                  code='invalid_choice')
+        return value
+
+
+class StateFilter(ModelChoiceFilter):
+
+    field_class = StateChoiceField
+
+
 class PatchFilter(ProjectMixin, FilterSet):
 
-    # TODO(stephenfin): We should probably be using a ChoiceFilter here?
-    state = CharFilter(name='state__name')
+    state = StateFilter(queryset=State.objects.all())
 
     class Meta:
         model = Patch
-        fields = ('project', 'series', 'submitter', 'delegate', 'state',
-                  'archived')
+        fields = ('project', 'series', 'submitter', 'delegate',
+                  'state', 'archived')
 
 
 class CheckFilter(TimestampMixin, FilterSet):
diff --git a/patchwork/api/patch.py b/patchwork/api/patch.py
index f0c7225..1f0ead1 100644
--- a/patchwork/api/patch.py
+++ b/patchwork/api/patch.py
@@ -70,7 +70,7 @@ class StateField(RelatedField):
             self.fail('incorrect_type', data_type=type(data).__name__)
 
     def to_representation(self, obj):
-        return '-'.join(obj.name.lower().split())
+        return obj.slug
 
     def get_queryset(self):
         return State.objects.all()
diff --git a/patchwork/models.py b/patchwork/models.py
index 8913fac..0ed37ab 100644
--- a/patchwork/models.py
+++ b/patchwork/models.py
@@ -192,6 +192,10 @@ class State(models.Model):
     ordering = models.IntegerField(unique=True)
     action_required = models.BooleanField(default=True)
 
+    @property
+    def slug(self):
+        return '-'.join(self.name.lower().split())
+
     def __str__(self):
         return self.name
 
diff --git a/patchwork/tests/test_rest_api.py b/patchwork/tests/test_rest_api.py
index 70410d0..0956010 100644
--- a/patchwork/tests/test_rest_api.py
+++ b/patchwork/tests/test_rest_api.py
@@ -309,7 +309,7 @@ class TestPatchAPI(APITestCase):
         self.assertEqual(patch_obj.id, patch_json['id'])
         self.assertEqual(patch_obj.name, patch_json['name'])
         self.assertEqual(patch_obj.msgid, patch_json['msgid'])
-        self.assertEqual(patch_obj.state.name, patch_json['state'])
+        self.assertEqual(patch_obj.state.slug, patch_json['state'])
         self.assertIn(patch_obj.get_mbox_url(), patch_json['mbox'])
 
         # nested fields
@@ -325,7 +325,8 @@ class TestPatchAPI(APITestCase):
         self.assertEqual(status.HTTP_200_OK, resp.status_code)
         self.assertEqual(0, len(resp.data))
 
-        patch_obj = create_patch()
+        state_obj = create_state(name='Under Review')
+        patch_obj = create_patch(state=state_obj)
 
         # anonymous user
         resp = self.client.get(self.api_url())
@@ -338,10 +339,9 @@ class TestPatchAPI(APITestCase):
         self.assertNotIn('diff', patch_rsp)
 
         # test filtering by state
-        other_state = create_state()
-        resp = self.client.get(self.api_url(), {'state': patch_obj.state.name})
+        resp = self.client.get(self.api_url(), {'state': 'under-review'})
         self.assertEqual([patch_obj.id], [x['id'] for x in resp.data])
-        resp = self.client.get(self.api_url(), {'state': other_state.name})
+        resp = self.client.get(self.api_url(), {'state': 'missing-state'})
         self.assertEqual(0, len(resp.data))
 
         # authenticated user
-- 
2.9.3