AA-164: Performance fixes for course home

lms/djangoapps/courseware/access_utils.py

@@ -65,7 +65,7 @@ def adjust_start_date(user, days_early_for_beta, start, course_key):
     return start
 
 
-def check_start_date(user, days_early_for_beta, start, course_key, display_error_to_user=True):
+def check_start_date(user, days_early_for_beta, start, course_key, display_error_to_user=True, now=None):
     """
     Verifies whether the given user is allowed access given the
     start date and the Beta offset for the given course.
@@ -82,10 +82,11 @@ def check_start_date(user, days_early_for_beta, start, course_key, display_error
     if start_dates_disabled and not masquerading_as_student:
         return ACCESS_GRANTED
     else:
-        now = datetime.now(UTC)
         if start is None or in_preview_mode() or get_course_masquerade(user, course_key):
             return ACCESS_GRANTED
 
+        if now is None:
+            now = datetime.now(UTC)
         effective_start = adjust_start_date(user, days_early_for_beta, start, course_key)
         if now > effective_start:
             return ACCESS_GRANTED

lms/djangoapps/courseware/courses.py

@@ -22,6 +22,8 @@ from opaque_keys.edx.keys import UsageKey
 from path import Path as path
 from six import text_type
 
+from openedx.core.lib.cache_utils import request_cached
+
 import branding
 from course_modes.models import CourseMode
 from lms.djangoapps.courseware.access import has_access
@@ -511,6 +513,7 @@ def get_course_assignment_date_blocks(course, user, request, num_return=None,
     return date_blocks
 
 
+@request_cached()
 def get_course_assignments(course_key, user, request, include_access=False):
     """
     Returns a list of assignment (at the subsection/sequential level) due dates for the given course.