Purpose/Overview:
Ability to browse by Instance classification number

Requirements/Scope:

1. Create new endpoint for classsification browse: GET /browse/classifications/instances

2. Should support filtering by classification type

   1. If classification type filter is missed then do browse by classificationNumber

   2. If classification type filter is exist then do browse by classificationShelvingOrder

Approach:

1. Combine search_after queries sorted by classificationNumber/classificationShelvingOrder around the anchor record

2. Use consortiumSearchHelper for consortium filtering and counts. See contributors/subjects browse service for reference.

Acceptance criteria:

• Covered by unit tests

• Module documentation updated

• Logging is well-defined