Forbid Blockstore access in LMS

[kdmccormick]

Background

The ADR "Limit LMS Modulestore access to the courseware app" explains why we want to limit and eventually remove the ability for LMS to access Modulestore. These same logic applies to Blockstore: we want Blockstore to be an authoring-only data store, with its content pushed into dedicated LMS models tailored to learning and instruction.

Currently, Blockstore is installed into both LMS and CMS, and there a few places where Blockstore can be accessed from LMS, such as the library_tools service. As of 2023, the number of these usage is fairly low, so now's a good time to tackle the issue before it gets more widespread.

Tasks

• Write docs explaining why Blockstore should only be used in the CMS
• Use tools like import-linting and ensure_cms() to find places where LMS uses Blockstore.
• Remove those LMS usages. Notes:
  • This can include: removing the library_tools service from the LMS xblock runtime.
  • Some LMS unit tests rely on being able to write to and read from block store in order to create their test data. We'll need to find a better way to create data for those tests.
• Un-install Blockstore from LMS.

[kdmccormick]

FYI @ormsbee , @connorhaugh

[kdmccormick]

Relates to:

• Move content_libraries to cms? #33428

[kdmccormick]

Blockstore was removed from edx-platform.