Upon upgrading to DSE 3, there seems to be an issue with group.query in solr.
This functionality only seems to work if the field which is being queried has the property 'required' set to true.
In all other fields, where 'required' is not set to true, if that field is queried in group.query, a NullPointerException is thrown.
For example:
If 'id' has required=true, and text does not,
group=true&group.query=id:"123ABC" works fine, but
group=true&group.query=text:"123ABC" throws a NullPointerException.
Below is the stacktrace:
java.lang.NullPointerException at org.apache.solr.search.grouping.distributed.shardresultserializer.TopGroupsResultTransformer.transformToNative(TopGroupsResultTransformer.java:110) at org.apache.solr.search.grouping.distributed.responseprocessor.TopGroupsShardResponseProcessor.process(TopGroupsShardResponseProcessor.java:80) at org.apache.solr.handler.component.QueryComponent.handleGroupedResponses(QueryComponent.java:620) at org.apache.solr.handler.component.QueryComponent.handleResponses(QueryComponent.java:603) at org.apache.solr.handler.component.SearchHandler.handleRequestBody(SearchHandler.java:317) at org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:129) at org.apache.solr.core.SolrCore.execute(SolrCore.java:1679) at org.apache.solr.servlet.SolrDispatchFilter.execute(SolrDispatchFilter.java:462) at com.datastax.bdp.cassandra.index.solr.CassandraDispatchFilter.execute(CassandraDispatchFilter.java:184) at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:276) at com.datastax.bdp.cassandra.index.solr.CassandraDispatchFilter.doFilter(CassandraDispatchFilter.java:134) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at ...
This issue with group.query did not exist in DSE 2.2
