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Introduction

This wiki explains current design of course batches, problems with it and proposed changes to the design and implementation to resolve the current issues and able to handle scale.

Background & Problem statement:

In current state changes stored in lms service are not reactive to any changes in the course content. This structure creates the issue when some of the contents changes and Sunbird uses locally stored copy of the content. For example, Once the user has completed the full course, if any unit is added or removed from the course, the changes are not dynamically reflected. There are use cases to enable this.

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Key Design Problems:

1. Easy way to maintain course details for a batch.
2. Better handling of course progress computation.
3. Easy to fetch data for given course or batch or user.

Design:

Managing Course Details:

Batches are created for a course. Course details are most of the time constant but, when the creator publishes it the data will be updated. So, copying the course details and saving along with course batch and user_courses is not good.

Option 1: Maintain cache with ttl

Option 2: Always fetch it from source

Solution Approach

A complete solution can be divided into below points

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