Filter entries by the presence of help types (#393)

Fix #392

README.md

@@ -239,6 +239,7 @@ The schema for the payload returned is:
 - `?tag=<string>` - Filter entries by a specific tag
 - `?issue=<string>` - Filter entries by an issue area
 - `?help_type=<string>` - Filter entries by a specific help category
+- `?has_help_types=<True or False>` - Filter entries by whether they have help types or not. Note that `True` or `False` is case-sensitive.
 - `?featured=<true or false>` - Filter featured or non-featured entries
 - `?ordering=<string>` - Order entries by a certain property e.g. `?ordering=title`. Prepend the property with a hyphen to get entries in descending order, e.g. `?ordering=-title`
 - `?moderationstate=<string>` - Filter entries by its moderation state. This filter will only be applied if the API call was made by an authenticated user with moderation permissions

pulseapi/entries/tests/test_staff_views.py

@@ -10,6 +10,7 @@ from rest_framework.request import Request
 from pulseapi.creators.models import EntryCreator
 from pulseapi.profiles.models import UserProfile
 from pulseapi.entries.models import Entry, ModerationState
+from pulseapi.helptypes.factory import HelpTypeFactory
 from pulseapi.entries.serializers import (
     EntrySerializerWithV1Creators,
     EntrySerializerWithCreators,
@@ -152,6 +153,31 @@ class TestEntryView(PulseStaffTestCase):
         )
         self.assertEqual(postresponse.status_code, 200)
 
+    def test_no_help_type_filter(self):
+        """Test filtering entries that don't have a help type"""
+        counter = 0
+        for entry in self.entries:
+            if counter % 2 == 0:
+                help_type = HelpTypeFactory()
+                entry.help_types.add(help_type)
+            else:
+                entry.help_types.clear()
+            counter += 1
+
+        entries_without_help_types = Entry.objects.filter(help_types__isnull=True).count()
+        entries_with_help_types = Entry.objects.filter(help_types__isnull=False).count()
+
+        url = reverse('entries-list', args=[settings.API_VERSIONS['version_2'] + '/'])
+        response_1 = self.client.get('{url}?has_help_types=False'.format(url=url))
+        response_entries_without_help_types = json.loads(str(response_1.content, 'utf-8'))
+        response_2 = self.client.get('{url}?has_help_types=True'.format(
+            url=reverse('entries-list', args=[settings.API_VERSIONS['version_2'] + '/']),
+        ))
+        response_entries_with_help_types = json.loads(str(response_2.content, 'utf-8'))
+
+        self.assertEqual(response_entries_without_help_types['count'], entries_without_help_types)
+        self.assertEqual(response_entries_with_help_types['count'], entries_with_help_types)
+
     def test_featured_filter(self):
         """Entry with all content"""
 

pulseapi/entries/views.py

@@ -167,6 +167,11 @@ class EntryCustomFilter(filters.FilterSet):
         name='help_types__name',
         lookup_expr='iexact',
     )
+    has_help_types = django_filters.BooleanFilter(
+        name='help_types',
+        lookup_expr='isnull',
+        exclude=True,
+    )
     featured = django_filters.BooleanFilter(
         name='featured'
     )
@@ -301,6 +306,9 @@ class EntriesListView(ListCreateAPIView):
     - `?tag=` - Allows filtering entries by a specific tag
     - `?issue=` - Allows filtering entries by a specific issue
     - `?help_type=` - Allows filtering entries by a specific help type
+    - `?has_help_types=<True or False>` - Filter entries by whether they have
+                                          help types or not. Note that `True`
+                                          or `False` is case-sensitive.
     - `?featured=True` (or False) - both capitalied. Boolean is set in admin UI
     - `?page=` - Page number, defaults to 1
     - `?page_size=` - Number of results on a page. Defaults to 48

pulseapi/helptypes/factory.py

@@ -0,0 +1,14 @@
+"""
+Create fake help types for local development, tests, and Heroku's review app.
+"""
+
+from factory import DjangoModelFactory, Faker
+
+from pulseapi.helptypes.models import HelpType
+
+
+class HelpTypeFactory(DjangoModelFactory):
+    name = Faker('job')
+
+    class Meta:
+        model = HelpType