Added support for filtering courses by one, or more, course keys

ECOM-5001

course_discovery/apps/api/filters.py

+import django_filters
 from django.contrib.auth import get_user_model
 from django.utils.translation import ugettext as _
 from drf_haystack.filters import HaystackFacetFilter
@@ -6,6 +7,8 @@ from dry_rest_permissions.generics import DRYPermissionFiltersBase
 from guardian.shortcuts import get_objects_for_user
 from rest_framework.exceptions import PermissionDenied, NotFound
 
+from course_discovery.apps.course_metadata.models import Course
+
 User = get_user_model()
 
 
@@ -52,3 +55,19 @@ class FacetQueryBuilderWithQueries(FacetQueryBuilder):
 
 class HaystackFacetFilterWithQueries(HaystackFacetFilter):
     query_builder_class = FacetQueryBuilderWithQueries
+
+
+class CharListFilter(django_filters.CharFilter):
+    def filter(self, qs, value):  # pylint: disable=method-hidden
+        if value not in (None, ''):
+            value = value.split(',')
+
+        return super(CharListFilter, self).filter(qs, value)
+
+
+class CourseFilter(django_filters.FilterSet):
+    keys = CharListFilter(name='key', lookup_type='in')
+
+    class Meta:
+        model = Course
+        fields = ['keys']

course_discovery/apps/api/v1/tests/test_views/test_courses.py

@@ -44,3 +44,13 @@ class CourseViewSetTests(SerializationMixin, APITestCase):
 
         response = self.client.get(url)
         self.assertListEqual(response.data['results'], self.serialize_course(courses, many=True))
+
+    def test_list_key_filter(self):
+        """ Verify the endpoint returns a list of courses filtered by the specified keys. """
+        courses = CourseFactory.create_batch(3)
+        courses = sorted(courses, key=lambda course: course.key.lower())
+        keys = ','.join([course.key for course in courses])
+        url = '{root}?keys={keys}'.format(root=reverse('api:v1:course-list'), keys=keys)
+
+        response = self.client.get(url)
+        self.assertListEqual(response.data['results'], self.serialize_course(courses, many=True))

course_discovery/apps/api/v1/views.py

@@ -16,14 +16,14 @@ from drf_haystack.mixins import FacetMixin
 from drf_haystack.viewsets import HaystackViewSet
 from dry_rest_permissions.generics import DRYPermissions
 from edx_rest_framework_extensions.permissions import IsSuperuser
-from rest_framework import status, viewsets
+from rest_framework import status, viewsets, filters
 from rest_framework.decorators import detail_route, list_route
 from rest_framework.exceptions import PermissionDenied, ParseError
 from rest_framework.permissions import IsAuthenticated
 from rest_framework.response import Response
 
 from course_discovery.apps.api import serializers
-from course_discovery.apps.api.filters import PermissionsFilter, HaystackFacetFilterWithQueries
+from course_discovery.apps.api.filters import PermissionsFilter, HaystackFacetFilterWithQueries, CourseFilter
 from course_discovery.apps.api.pagination import PageNumberPagination
 from course_discovery.apps.api.renderers import AffiliateWindowXMLRenderer, CourseRunCSVRenderer
 from course_discovery.apps.catalogs.models import Catalog
@@ -172,6 +172,8 @@ class CatalogViewSet(viewsets.ModelViewSet):
 
 class CourseViewSet(viewsets.ReadOnlyModelViewSet):
     """ Course resource. """
+    filter_backends = (filters.DjangoFilterBackend,)
+    filter_class = CourseFilter
     lookup_field = 'key'
     lookup_value_regex = COURSE_ID_REGEX
     queryset = Course.objects.all()
@@ -190,10 +192,16 @@ class CourseViewSet(viewsets.ReadOnlyModelViewSet):
 
     def list(self, request, *args, **kwargs):
         """ List all courses.
-        ---
+         ---
         parameters:
             - name: q
-              description: Elasticsearch querystring query
+              description: Elasticsearch querystring query. This filter takes precedence over other filters.
+              required: false
+              type: string
+              paramType: query
+              multiple: false
+            - name: keys
+              description: Filter by keys (comma-separated list)
               required: false
               type: string
               paramType: query

course_discovery/settings/base.py

@@ -41,6 +41,7 @@ THIRD_PARTY_APPS = (
     'guardian',
     'dry_rest_permissions',
     'compressor',
+    'django_filters',
 )
 
 PROJECT_APPS = (

requirements/base.txt

 cryptography==1.4
 django==1.8.14
 django-extensions==1.6.7
+django-filter==0.13.0
 django-guardian==1.4.4
 django-haystack==2.4.1
 django-libsass==0.7