This will allow v1 code of CourseOverview to delete entries. While
this is not a good thing in general (and future versions will ignore
entries with higher versions than they support), this is necessary
to prevent errors with the existing code in a rollback situation.
Otherwise, old code trying to delete CourseOverview entries will
fail with a foreign key constraint violation.
Previously, CourseOverview would delete data for any version
that didn't match the current one. That could cause problems
during deploys, when multiple versions of CourseOverview
were active. They would overwrite each other, and that could
cause problems if the old one overwrote the new one -- in
our case, the new one created a new table with foreign key
links that the old one was unaware of, and trying to delete
it would have caused an error.
- Course overviews will cache courses upon publish.
- Added management command to warm up cache.
- OAuth2 handler returns courses via course overviews.
enrollments.
The goal for this PR is to have a single mechanism for registering users and
reducing the number of places where special-casing for ccx courses is needed. The
migration at this point is purposefully limited to convert ccx memberships into
student enrollments when moving forward. No backward migration is in place at the
moment. The ccx membership tables are not removed at this time. It is possible to go
backwards and forwards multiple times with no errors or data loss.
What happened:
* First, I merged `0004_default_lowest_passing_grade_to_None.py`, which adds `null=True` to `lowest_passing_grade`.
* Later, Renzo merged `0004_auto__add_field_courseoverview_enrollment_start__add_field_courseoverv.py`, which adds a bunch of enrollment-related fields
* Neither migrations' `models` variables reflects the changes in the other one.
* release currently has just `0004_default...`
* master and rc/2015-07-22 have `0004_auto...` and `0004_default...`, in that order.
What this commit changes:
* Change `0004_auto...` to `0005_add_enrollment_fields.py`
* Update `models` in `0005_...` to have `null=True` for `lowest_passing_grade`
Sets the Enrollment API free of the modulestore by replacing modulestore queries with calls to the CourseOverview model. Course deletion invalidates the corresponding CourseOverview. XCOM-462.
Celery requires all tasks to be in a tasks module. Also, the task has been updated to use default values if the the course structure generator encounters a block without the graded or format fields.
