Refactor course deletion

[weiqingtoh]

Currently the course deletion takes a long time because we rely on callbacks to delete all course related objects. This requires the server to instantiate each record in ActiveRecord which is time and memory intensive, and could possible result in stack-overflow.

There are probably many ways to do this, but some possible ways include:

• Ensure that each component handle its own deletion; or
• Define a few top-level course objects, which would each have its own deletion logic.

The subsequent deletion of objects can be implemented as jobs (invoked with execute_after_commit) to ensure that the user doesn't get stuck waiting for the entire course to delete.

[benleong]

Another concern is that as more and more new items are developed, one of the new components might introduce a bug that chokes the deletion process.

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On Sat, Sep 16, 2017 at 10:27 AM, Weiqing ***@***.***> wrote: Currently the course deletion takes a long time because we rely on callbacks to delete all course related objects. This requires the server to instantiate each record in ActiveRecord which is time and memory intensive, and could possible result in stack-overflow. There are probably many ways to do this, but some possible ways include: - Ensure that each component handle its own deletion; or - Define a few top-level course objects, which would each have its own deletion logic. The subsequent deletion of objects can be implemented as jobs (invoked with execute_after_commit) to ensure that the user doesn't get stuck waiting for the entire course to delete. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#2511>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABPMdUmYU4M3hAmgJ9MIASieOXMhIQ7xks5sizIbgaJpZM4PZrRI> .

[weiqingtoh]

The idea is that we delegate the deletion logic to each component or module or top-level objects to handle. If there are bugs: (1) at least lecturers can delete courses, and (2) it will be easier for us to clean this up backend.