This patch modifies the way copy data is shared in order to mitigate potential race conditions
and ensure that the serialised controller stored in the DB is always in a valid state.
The restore controller is now considered the "source of truth" for all information about the
copy operation. Backup controllers can no longer contain information about course copies.
As copy creation is not atomic, it is still possible for copy controllers to become orphaned or
exist in an invalid state. To mitigate this the backup cleanup task has been modified to call
a new helper method copy_helper::cleanup_orphaned_copy_controllers.
Summary of changes in this patch:
- Copy data must now be passed through the restore controller's constructor
- base_controller::get_copy has been deprecated in favour of restore_controller::get_copy
- base_controller::set_copy has been deprecated without replacement
- core_backup\copy\copy has been deprecated, use copy_helper.class.php's copy_helper instead
- backup_cleanup_task will now clean up orphaned controllers from copy operations that went awry
Thanks to Peter Burnett for assiting with testing this patch.
Centralise management of all types of cron tasks with registration, scheduling,
parallel task conflicts(blocking) and running once off tasks, all using an
administration screen.
This is a combination of several issues:
MDL-25502: Added "black magic" task allocator for cron
MDL-25503: Add step to cron to run all scheduled tasks
MDL-25504 cron: Refactor to use scheduler
MDL-25505: Add an admin interface to schedule tasks via cron.
MDL-25507: Add support for adhoc tasks.
