more granular transactions in grading [LMS-1480]

remove field_data_cache from grades.grade and grades.progress_summary

cleans grading code by adding wrappers

lms/djangoapps/courseware/tests/test_submitting_problems.py

@@ -236,14 +236,11 @@ class TestCourseGrader(TestSubmittingProblems):
             make up the final grade. (For display)
         """
 
-        field_data_cache = FieldDataCache.cache_for_descriptor_descendents(
-            self.course.id, self.student_user, self.course)
-
-        fake_request = self.factory.get(reverse('progress',
-                                        kwargs={'course_id': self.course.id}))
+        fake_request = self.factory.get(
+            reverse('progress', kwargs={'course_id': self.course.id})
+        )
 
-        return grades.grade(self.student_user, fake_request,
-                            self.course, field_data_cache)
+        return grades.grade(self.student_user, fake_request, self.course)
 
     def get_progress_summary(self):
         """
@@ -257,16 +254,13 @@ class TestCourseGrader(TestSubmittingProblems):
         etc.
         """
 
-        field_data_cache = FieldDataCache.cache_for_descriptor_descendents(
-            self.course.id, self.student_user, self.course)
-
-        fake_request = self.factory.get(reverse('progress',
-                                        kwargs={'course_id': self.course.id}))
+        fake_request = self.factory.get(
+            reverse('progress', kwargs={'course_id': self.course.id})
+        )
 
-        progress_summary = grades.progress_summary(self.student_user,
-                                                   fake_request,
-                                                   self.course,
-                                                   field_data_cache)
+        progress_summary = grades.progress_summary(
+            self.student_user, fake_request, self.course
+        )
         return progress_summary
 
     def check_grade_percent(self, percent):

lms/djangoapps/courseware/views.py

@@ -14,6 +14,7 @@ from django.shortcuts import redirect
 from mitxmako.shortcuts import render_to_response, render_to_string
 from django_future.csrf import ensure_csrf_cookie
 from django.views.decorators.cache import cache_control
+from django.db import transaction
 from markupsafe import escape
 
 from courseware import grades
@@ -643,8 +644,9 @@ def mktg_course_about(request, course_id):
     except (ValueError, Http404) as e:
         # if a course does not exist yet, display a coming
         # soon button
-        return render_to_response('courseware/mktg_coming_soon.html',
-                                  {'course_id': course_id})
+        return render_to_response(
+            'courseware/mktg_coming_soon.html', {'course_id': course_id}
+        )
 
     registered = registered_for_course(course, request.user)
 
@@ -659,7 +661,8 @@ def mktg_course_about(request, course_id):
                             settings.MITX_FEATURES.get('ENABLE_LMS_MIGRATION'))
     course_modes = CourseMode.modes_for_course(course.id)
 
-    return render_to_response('courseware/mktg_course_about.html',
+    return render_to_response(
+        'courseware/mktg_course_about.html',
         {
             'course': course,
             'registered': registered,
@@ -667,13 +670,27 @@ def mktg_course_about(request, course_id):
             'course_target': course_target,
             'show_courseware_link': show_courseware_link,
             'course_modes': course_modes,
-                              })
+        }
+    )
 
 
 @login_required
 @cache_control(no_cache=True, no_store=True, must_revalidate=True)
+@transaction.commit_manually
 def progress(request, course_id, student_id=None):
-    """ User progress. We show the grade bar and every problem score.
+    """
+    Wraps "_progress" with the manual_transaction context manager just in case
+    there are unanticipated errors.
+    """
+    with grades.manual_transaction():
+        return _progress(request, course_id, student_id)
+
+
+def _progress(request, course_id, student_id):
+    """
+    Unwrapped version of "progress".
+
+    User progress. We show the grade bar and every problem score.
 
     Course staff are allowed to see the progress of students in their class.
     """
@@ -696,26 +713,26 @@ def progress(request, course_id, student_id=None):
     # additional DB lookup (this kills the Progress page in particular).
     student = User.objects.prefetch_related("groups").get(id=student.id)
 
-    field_data_cache = FieldDataCache.cache_for_descriptor_descendents(
-        course_id, student, course, depth=None)
+    courseware_summary = grades.progress_summary(student, request, course)
 
-    courseware_summary = grades.progress_summary(student, request, course,
-                                                 field_data_cache)
-    grade_summary = grades.grade(student, request, course, field_data_cache)
+    grade_summary = grades.grade(student, request, course)
 
     if courseware_summary is None:
         #This means the student didn't have access to the course (which the instructor requested)
         raise Http404
 
-    context = {'course': course,
+    context = {
+        'course': course,
         'courseware_summary': courseware_summary,
         'grade_summary': grade_summary,
         'staff_access': staff_access,
         'student': student,
     }
-    context.update()
 
-    return render_to_response('courseware/progress.html', context)
+    with grades.manual_transaction():
+        response = render_to_response('courseware/progress.html', context)
+
+    return response
 
 
 @login_required