[SOLR-13720] Impossible to create effective ToParenBlockJoinQuery in custom QParser

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 8.2
• Fix Version/s: 8.3
• Component/s: query parsers
• Labels: noob
• Assignee: Mikhail Khludnev
• Reporter: Stanislav Livotov
• Created: 26/Aug/19 17:00
• Updated: 21/Jan/20 16:59
• Resolved: 29/Aug/19 15:05

Description

According to Solr documentation  QParser is treated as a legal plugin.

 

However, it is impossible to create an effective ToParentBlockJoin query without copy-pasting(BitDocIdSetFilterWrapper class and getCachedFilter method from BlockJoinParentQParser) or dirty hacks(like creating org.apache.solr.search.join package with some accessor method to package-private methods in plugin code and adding it in WEB-INF/lib directory in order to be loaded by the same ClassLoader).

I don't see a truly clean way how to fix it, but at least we can help custom plugin developers to create it a little bit easier by making BlockJoinParentQParser#getCachedFilter public and BlockJoinParentQParser#BitDocIdSetFilterWrapper and providing getter for BitDocIdSetFilterWrapper#filter. 

 

 

In order to create