update CourseGoalViewSet to return status=400 if no goal key is provided LEARNER-3342

lms/djangoapps/course_goals/tests/test_api.py

@@ -55,6 +55,17 @@ class TestCourseGoalsAPI(EventTrackingTestCase, SharedModuleStoreTestCase):
         self.assertEqual(response.status_code, 400)
         self.assertEqual(len(CourseGoal.objects.filter(user=self.user, course_key=self.course.id)), 0)
 
+    def test_add_without_goal_key(self):
+        """ Ensures if no goal key provided, post does not succeed. """
+
+        response = self.post_course_goal(goal_key=None)
+        self.assertEqual(len(CourseGoal.objects.filter(user=self.user, course_key=self.course.id)), 0)
+        self.assertContains(
+            response=response,
+            text='Please provide a valid goal key from following options.',
+            status_code=400
+        )
+
     @mock.patch('lms.djangoapps.course_goals.views.update_google_analytics')
     @override_settings(LMS_SEGMENT_KEY="foobar")
     def test_update_goal(self, ga_call):
@@ -74,12 +85,12 @@ class TestCourseGoalsAPI(EventTrackingTestCase, SharedModuleStoreTestCase):
         Sends a post request to set a course goal and returns the response.
         """
         goal_key = goal_key if valid else 'invalid'
-        response = self.client.post(
-            self.apiUrl,
-            {
-                'goal_key': goal_key,
-                'course_key': self.course.id,
-                'user': self.user.username,
-            },
-        )
+        post_data = {
+            'course_key': self.course.id,
+            'user': self.user.username,
+        }
+        if goal_key:
+            post_data['goal_key'] = goal_key
+
+        response = self.client.post(self.apiUrl, post_data)
         return response

lms/djangoapps/course_goals/views.py

@@ -61,8 +61,15 @@ class CourseGoalViewSet(viewsets.ModelViewSet):
         """ Create a new goal if one does not exist, otherwise update the existing goal. """
         # Ensure goal_key is valid
         goal_options = get_course_goal_options()
-        goal_key = post_data.data['goal_key']
-        if goal_key not in goal_options:
+        goal_key = post_data.data.get('goal_key')
+        if not goal_key:
+            return Response(
+                'Please provide a valid goal key from following options. (options= {goal_options}).'.format(
+                    goal_options=goal_options,
+                ),
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+        elif goal_key not in goal_options:
             return Response(
                 'Provided goal key, {goal_key}, is not a valid goal key (options= {goal_options}).'.format(
                     goal_key=goal_key,