[LUCENE-9944] Implement alternative drill sideways faceting with provided CollectorManager

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 9.0
• Fix Version/s: 9.0, 8.10
• Component/s: modules/facet
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: Greg Miller
• Created: 29/Apr/21 16:16
• Updated: 28/Aug/22 16:21
• Resolved: 02/Jun/21 13:32

Description

Today, if a user of DrillSideways wants to provide their own CollectorManager when invoking search, they get this alternate, "concurrent" implementation that creates N copies of the provided DrillDownQuery (where N is the number of drill-down dimensions) and runs them all concurrently. This is a very different implementation than the one a user would get if providing a Collector instead. Additionally, an ExecutorService must be provided when constructing a DrillSideways instance if the user wants to bring their own CollectorManager (otherwise, they'll get an unfriendly NPE when calling search).

I propose adding an implementation to DrillSideways that will run the "non-concurrent" algorithm in the case that a user wants to provide their own CollectorManager but doesn't want to provide an ExecutorService (and doesn't want the concurrent algorithm).

Issue Links

• links to: GitHub Pull Request #142