The "contentstore" is where all course assets are stored. It's really a wrapper of code around a GridFS (MongoDB) backend and it stores binary files which can PDFs, WAVs, JPGs, or other. The contentstore code is mainly here:

edx-platform/common/lib/xmodule/xmodule/contentstore

Counting Assets in Each Course

If you need to find out how many assets are contained in each course, the JS below will assist you.

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