Fix error case where we have items in our grading csv output

that are not present in a given student's gradeset.

General code cleanup and addition of comments.

Instructor dashboard API unit tests.

LMS-58

lms/djangoapps/instructor/tests/test_api.py

@@ -29,7 +29,6 @@ from courseware.models import StudentModule
 
 # modules which are mocked in test cases.
 import instructor_task.api
-
 from instructor.access import allow_access
 import instructor.views.api
 from instructor.views.api import _split_input_list, _msk_from_problem_urlname, common_exceptions_400
@@ -128,6 +127,8 @@ class TestInstructorAPIDenyLevels(ModuleStoreTestCase, LoginEnrollmentTestCase):
             ('send_email', {'send_to': 'staff', 'subject': 'test', 'message': 'asdf'}),
             ('list_instructor_tasks', {}),
             ('list_background_email_tasks', {}),
+            ('list_grade_downloads', {}),
+            ('calculate_grades_csv', {}),
         ]
         # Endpoints that only Instructors can access
         self.instructor_level_endpoints = [
@@ -790,6 +791,50 @@ class TestInstructorAPILevelsDataDump(ModuleStoreTestCase, LoginEnrollmentTestCa
         self.assertTrue(body.startswith('"User ID","Anonymized user ID"\n"2","42"\n'))
         self.assertTrue(body.endswith('"7","42"\n'))
 
+    def test_list_grade_downloads(self):
+        url = reverse('list_grade_downloads', kwargs={'course_id': self.course.id})
+        with patch('instructor_task.models.LocalFSGradesStore.links_for') as mock_links_for:
+            mock_links_for.return_value = [
+                ('mock_file_name_1', 'https://1.mock.url'),
+                ('mock_file_name_2', 'https://2.mock.url'),
+            ]
+            response = self.client.get(url, {})
+
+        expected_response = {
+            "downloads": [
+                {
+                    "url": "https://1.mock.url",
+                    "link": "<a href=\"https://1.mock.url\">mock_file_name_1</a>",
+                    "name": "mock_file_name_1"
+                },
+                {
+                    "url": "https://2.mock.url",
+                    "link": "<a href=\"https://2.mock.url\">mock_file_name_2</a>",
+                    "name": "mock_file_name_2"
+                }
+            ]
+        }
+        res_json = json.loads(response.content)
+        self.assertEqual(res_json, expected_response)
+
+    def test_calculate_grades_csv_success(self):
+        url = reverse('calculate_grades_csv', kwargs={'course_id': self.course.id})
+
+        with patch('instructor_task.api.submit_calculate_grades_csv') as mock_cal_grades:
+            mock_cal_grades.return_value = True
+            response = self.client.get(url, {})
+        success_status = "Your grade report is being generated! You can view the status of the generation task in the 'Pending Instructor Tasks' section."
+        self.assertIn(success_status, response.content)
+
+    def test_calculate_grades_csv_already_running(self):
+        url = reverse('calculate_grades_csv', kwargs={'course_id': self.course.id})
+
+        with patch('instructor_task.api.submit_calculate_grades_csv') as mock_cal_grades:
+            mock_cal_grades.side_effect = AlreadyRunningError()
+            response = self.client.get(url, {})
+        already_running_status = "A grade report generation task is already in progress. Check the 'Pending Instructor Tasks' table for the status of the task. When completed, the report will be available for download in the table below."
+        self.assertIn(already_running_status, response.content)
+
     def test_get_students_features_csv(self):
         """
         Test that some minimum of information is formatted
@@ -802,7 +847,7 @@ class TestInstructorAPILevelsDataDump(ModuleStoreTestCase, LoginEnrollmentTestCa
     def test_get_distribution_no_feature(self):
         """
         Test that get_distribution lists available features
-        when supplied no feature quparameter.
+        when supplied no feature parameter.
         """
         url = reverse('get_distribution', kwargs={'course_id': self.course.id})
         response = self.client.get(url)