Merge pull request #10363 from edx/saleem-latif/SOL-1315

SOL-1315: Add Cert Exception UI on Instructor Dash

lms/djangoapps/instructor_task/api.py

@@ -491,3 +491,24 @@ def generate_certificates_for_all_students(request, course_key):   # pylint: dis
     task_key = ""
 
     return submit_task(request, task_type, task_class, course_key, task_input, task_key)
+
+
+def generate_certificates_for_students(request, course_key, students=None):  # pylint: disable=invalid-name
+    """
+    Submits a task to generate certificates for given students enrolled in the course or
+    all students if argument 'students' is None
+
+    Raises AlreadyRunningError if certificates are currently being generated.
+    """
+    if students:
+        task_type = 'generate_certificates_certain_student'
+        students = [student.id for student in students]
+        task_input = {'students': students}
+    else:
+        task_type = 'generate_certificates_all_student'
+        task_input = {}
+
+    task_class = generate_certificates
+    task_key = ""
+
+    return submit_task(request, task_type, task_class, course_key, task_input, task_key)

lms/djangoapps/instructor_task/tasks_helper.py

@@ -1398,11 +1398,17 @@ def upload_proctored_exam_results_report(_xmodule_instance_args, _entry_id, cour
 def generate_students_certificates(
         _xmodule_instance_args, _entry_id, course_id, task_input, action_name):  # pylint: disable=unused-argument
     """
-    For a given `course_id`, generate certificates for all students
-    that are enrolled.
+    For a given `course_id`, generate certificates for only students present in 'students' key in task_input
+    json column, otherwise generate certificates for all enrolled students.
     """
     start_time = time()
     enrolled_students = CourseEnrollment.objects.users_enrolled_in(course_id)
+
+    students = task_input.get('students', None)
+
+    if students is not None:
+        enrolled_students = enrolled_students.filter(id__in=students)
+
     task_progress = TaskProgress(action_name, enrolled_students.count(), start_time)
 
     current_step = {'step': 'Calculating students already have certificates'}

lms/djangoapps/instructor_task/tests/test_tasks_helper.py

@@ -9,6 +9,7 @@ Tests that CSV grade report generation works with unicode emails.
 import ddt
 from mock import Mock, patch
 import tempfile
+import json
 from openedx.core.djangoapps.course_groups import cohorts
 import unicodecsv
 from django.core.urlresolvers import reverse
@@ -1611,12 +1612,18 @@ class TestCertificateGeneration(InstructorTaskModuleTestCase):
 
         current_task = Mock()
         current_task.update_state = Mock()
+        instructor_task = Mock()
+        instructor_task.task_input = json.dumps({'students': None})
         with self.assertNumQueries(125):
             with patch('instructor_task.tasks_helper._get_current_task') as mock_current_task:
                 mock_current_task.return_value = current_task
                 with patch('capa.xqueue_interface.XQueueInterface.send_to_queue') as mock_queue:
                     mock_queue.return_value = (0, "Successfully queued")
-                    result = generate_students_certificates(None, None, self.course.id, None, 'certificates generated')
+                    with patch('instructor_task.models.InstructorTask.objects.get') as instructor_task_object:
+                        instructor_task_object.return_value = instructor_task
+                        result = generate_students_certificates(
+                            None, None, self.course.id, {}, 'certificates generated'
+                        )
         self.assertDictContainsSubset(
             {
                 'action_name': 'certificates generated',