SB-29845: Paging on User Enrollment List

Overview:

Currently, user enrollment list API returns a list of fixed size 1000. We are not able to get enrollments records with user enrollments when greater than 1000 . We will need to introduce paging mechanism.

Pr-requisites:

User is a logged in user and has enrolled into at-least one traceable collection

Linked Issues:

https://project-diksha.atlassian.net/browse/DIK-6248

https://project-sunbird.atlassian.net/browse/SB-28497

Solutions:

Paging mechanism in the user enrollment list API .

2. Batch calls for course composite search API with limit of 1000.

Option 1: Paging mechanism in the user enrollment list API.

Details:

Introducing paging for user enrollment list API.

Add 2 parameters as offset and limit. Offset is the page state Limit is the number of records

request.getContext.get("pageIndex").asInstanceOf[String])
request.getContext.get("size").asInstanceOf[Integer])

Steps to follow:

New implementation in CassandraOperation as
  
  Response getRecordByIdentifier(RequestContext requestContext, String keyspaceName,
   String tableName, Object key, List<String> fields,
   int size, String pageIndex);
   
   1. Select query has to be modified with limit
        selectStatement.setFetchSize(size);
  
   2. Select query modification with offset
        if (!pageIndex.equals("0")) {
              selectStatement.setPagingState(PagingState.fromString(pageIndex));
          }

Pros:

Better performance in API due to pagination

Cons:

Portal and back-end implementation required

Option 2: Batch calls for course composite search API with limit of 1000.

Details:

Pros:

Cons: