When crawlers like edX-downloader make requests on courseware, they are
often concurrently loading many units in the same sequence. This causes
contention for the rows in courseware_studentmodule that store the
student's state for various XBlocks/XModules, most notably for the
sequence, chapter, and course -- all of which record and update user
position information when loaded.
It would be nice if we could actually remove these writes altogether
and come up with a cleaner way of keeping track of the user's position.
In general, GETs should be side-effect free. However, any such change
would break backwards compatibility, and would require close
coordination with research teams to make sure they weren't negatively
affected.
This commit identifies crawlers by user agent (CrawlersConfig model),
and blocks student state writes if a crawler is detected. FieldDataCache
writes simply become no-ops. It doesn't actually alter the rendering
of the courseware in any way -- the main impact is that the blocks
won't record your most recent position, which is meaningless for
crawlers anyway.
This can also be used as a building block for other policy we want to
define around crawlers. We just have to be mindful that this only works
with "nice" crawlers who are honest in their user agents, and that
significantly more sophisticated (and costly) measures would be
necessary to prevent crawlers that try to be even trivially sneaky.
[PERF-403]
[courseware] generate sequence-specific titles server-side (AC-695)
[courseware] generate sequence-specific titles server-side (AC-695)
case for empty subsections [AC-695]
move title logic into courseware context method [AC-695]
pep8
coffeescript -> js
js mistake
jslint
refactor sequence title generation slightly
missed a line
line too long
python is not javascript
ugh js
ugh js part 2
instead of using the base course key (which does not contain the CCX info).
This removes the need for special checking of CCXKey/CCXLocator types, and just
treats them like normal CourseKeys.
This fix allows users with a Staff role on a CCX course to view CCX courses in Insights.
Remove deprecated SingleSectionGrader. TNL-5987
Remove display_name and module_id from Scores objects
Update CourseGradeFactory.__init__ to not be user-specific
Update some callers to use CourseGrade class instead of "summary" dict
Remove no longer needed course_grades.py module.
Renamed django signal from GRADES_UPDATED to COURSE_GRADE_CHANGED
Makes use of the new SUBSECTION_SCORE_CHANGED signal to trigger a task that
updates persisted course grade values. We've also renamed SCORE_CHANGED to
PROBLEM_SCORE_CHANGED to head off any issues with unclear signal names.
TNL-5740
For better user-facing performance, the SCORE_CHANGED signal is now handled by
enqueueing an async task to update the relevant stored grade, rather than
making the request wait until that operation finishes.
TNL-5738
