Currently the search update pipeline relies on kafka streams emitted -- amongst other sources -- from EventBus. That is not the case for private wikis, such as office.wikimedia.org.
As discussed on 23-09-11 a clone of the page_change stream that is dedicated to private wikis might be an option.
Minimum set of streams that are needed:
- mediawiki.page_change.v1
- mediawiki.cirrussearch.page_rerender.v1