Purpose/Overview:

Catalogers want the ability to review any changes to linked authority record + bib records to aid in authority control and overall catalog maintenance.

In a scope of this story we need to implement job for `AUTH_HEADINGS_UPDATES` ExportType, based on requirements from UIMARCAUTH-209.

Approach:

• create reader which will use client method `GET /links/authority/stats` to retrieve statistics

• reader should work with chunks (configurable through env variable). See `DatabaseEHoldingsReader` for seek method usage reference

• create processor to convert data to export format. Format described in mentioned above requirements task.

• create writer that will write read data to csv file, see `EHoldingsCsvFileWriter` for reference

• writer should work with chunks

• there should be separate chunk config variables for http reads and spring batch chunk processing, see config for eHoldings job

• create job config which will provide `Job` bean, see `EHoldingsJobConfig` for reference

• job should consist of one step with reader, processor, writer, listener. No need to use the database because all data queried from one source and so can be written immediately

Whole job should work in batches: read batch from mod-entities-links, write batch to file; after all batches processed - upload file

Acceptance criteria:

• Covered by unit tests

• Karate tests are created/updated

• Module documentation updated

• Logging is well-defined