Added courses_count field to Catalog model and API endpoint

ECOM-3973

course_discovery/apps/api/serializers.py

@@ -6,11 +6,9 @@ from course_discovery.apps.course_metadata.models import Course
 
 
 class CatalogSerializer(serializers.ModelSerializer):
-    url = serializers.HyperlinkedIdentityField(view_name='api:v1:catalog-detail', lookup_field='id')
-
     class Meta(object):
         model = Catalog
-        fields = ('id', 'name', 'query', 'url',)
+        fields = ('id', 'name', 'query', 'courses_count',)
 
 
 class CourseSerializer(serializers.ModelSerializer):

course_discovery/apps/api/tests/test_serializers.py

-from django.core.urlresolvers import reverse
-from django.test import TestCase, RequestFactory
+from django.test import TestCase
 
 from course_discovery.apps.api.serializers import CatalogSerializer, CourseSerializer, ContainedCoursesSerializer
 from course_discovery.apps.catalogs.tests.factories import CatalogFactory
@@ -8,16 +7,15 @@ from course_discovery.apps.course_metadata.tests.factories import CourseFactory
 
 class CatalogSerializerTests(TestCase):
     def test_data(self):
-        catalog = CatalogFactory()
-        path = reverse('api:v1:catalog-detail', kwargs={'id': catalog.id})
-        request = RequestFactory().get(path)
-        serializer = CatalogSerializer(catalog, context={'request': request})
+        catalog = CatalogFactory(query='*:*')  # We intentionally use a query for all Courses.
+        courses = CourseFactory.create_batch(10)
+        serializer = CatalogSerializer(catalog)
 
         expected = {
             'id': catalog.id,
             'name': catalog.name,
             'query': catalog.query,
-            'url': request.build_absolute_uri(),
+            'courses_count': len(courses)
         }
         self.assertDictEqual(serializer.data, expected)
 
@@ -25,9 +23,7 @@ class CatalogSerializerTests(TestCase):
 class CourseSerializerTests(TestCase):
     def test_data(self):
         course = CourseFactory()
-        path = reverse('api:v1:course-detail', kwargs={'key': course.key})
-        request = RequestFactory().get(path)
-        serializer = CourseSerializer(course, context={'request': request})
+        serializer = CourseSerializer(course)
 
         expected = {
             'key': course.key,

course_discovery/apps/catalogs/models.py

@@ -32,6 +32,10 @@ class Catalog(ModelPermissionsMixin, TimeStampedModel):
         results = self._get_query_results().load_all()
         return [result.object for result in results]
 
+    @property
+    def courses_count(self):
+        return self._get_query_results().count()
+
     def contains(self, course_ids):  # pylint: disable=unused-argument
         """ Determines if the given courses are contained in this catalog.
 

course_discovery/apps/catalogs/tests/factories.py

@@ -9,4 +9,4 @@ class CatalogFactory(factory.DjangoModelFactory):
         model = Catalog
 
     name = FuzzyText(prefix='catalog-name-')
-    query = '{"query": {"match_all": {}}}'
+    query = '*:*'

course_discovery/apps/catalogs/tests/test_models.py

@@ -34,3 +34,12 @@ class CatalogTests(ElasticsearchTestMixin, TestCase):
             self.catalog.contains([self.course.key, uncontained_course.key]),
             {self.course.key: True, uncontained_course.key: False}
         )
+
+    def test_courses_count(self):
+        """ Verify the method returns the number of courses contained in the Catalog. """
+        self.assertEqual(self.catalog.courses_count, 1)
+
+        # Create a new course that should NOT be contained in the catalog, and one that should
+        CourseFactory()
+        CourseFactory(title='ABCDEF')
+        self.assertEqual(self.catalog.courses_count, 2)