Design: Last access time for collection & resources

Owned by Pritha Chattopadhyay
Last updated: Dec 23, 2021
2 min read

 

Overview

To organise the any order of tractable collection w.r.t user’s last access date and time on the user enrolment list . We have two solution approach.

Referenced ticket: https://project-sunbird.atlassian.net/browse/SB-26283

Pre-requisites:

  1. User is a logged in user and has enrolled into at-least one trackable collection

Solutions:

 

  1. Adding new metadata to User’s enrolment

  2. Re-using last access time from User content consumption

 

Option 1: Adding new metadata to User’s enrolment :

 

Adding a metadata to User’s enrollment component as last access timestamp. This metadata needs to updated while updating last accessed content id for a user. Also for the old records for this metadata requires a migration.

 

Steps to follow

  1. Add new column to user_enrolments table

ALTER TABLE sunbird_courses.user_enrolments ADD last_content_access_time timestamp

2. Update the metadata by user content state update Api

3. Migration on old user_enrolments records data migration for new column needed using user_content_comsumption table

4. Order the records for list enrolment api to get the expected response

 

Pros:

  • The ordering process is cleaner and easier

Cons:

  • Duplicate data in multiple tables

  • Migration is required for existing enrolments.

Option 2: Re-using last access time from User content consumption:

 

While fetch list of user enrolments join user content consumption by the last access content id to get the last access timestamp filter by the user id, course id, batch id and last access content id and formulate the response accordingly. This approach would not require the migration steps

 

Steps to follow:

  1. List enrolment Api for a given user id , make a new DB call for user_content_comsumption based on user id, batch id, course id and last content id lastreadcontentid from each records of user_enrolments

  2. Merge the response with user_content_comsumption.last_access_time. Order the records

 

Pros:

  • No migration required.

  • Backward compatibility is handled

Cons:

  • API might become slower as we connect to multiple tables.

 

Conclusion

The last time access collection to be implemented by adding a new column (option 1). No migration is required as update user content state API is frequently called.