[SOLR-2893] NPE in JSONWriter during Distributed Search w/Grouping

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Not A Problem
• Affects Version/s: 4.0-ALPHA
• Component/s: search

Environment

java version "1.6.0_18"
OpenJDK Runtime Environment (IcedTea6 1.8) (fedora-41.b18.fc13-x86_64)
OpenJDK 64-Bit Server VM (build 14.0-b16, mixed mode)

• Assignee: Unassigned
• Reporter: Michael Garski
• Created: 11/Nov/11 22:00
• Updated: 20/Apr/17 15:12
• Resolved: 20/Apr/17 15:12

Description

I am doing some testing with a nightly build from 11/4/2011 and I regularly encounter an NPE in the JSONWriter when performing a distributed search with grouping on a single numeric field. The same searches non-distributed do not encounter this issue.

Here is the query being used: facet=off&shards=searcher1-vip:8983/solr/core_0,searcher2-vip:8983/solr/core_1,localhost:8983/solr/core_2&start=0&shards.qt=/item/search&q=nova+y+jory&wt=json&fq=country:ww+OR+country:us&fq=stream:1&rows=4

Here is the handler configuration:

<requestHandler name="/item/search" class="solr.SearchHandler">
<lst name="invariants">
<str name="echoParams">explicit</str>
<str name="json.nl">map</str>

<!-- Query settings -->
<str name="defType">dismax</str>
<str name="qf">title name^2.0</str>
<str name="pf2">title name^2.0</str>
<int name="ps2">2</int>
<str name="bf">product(apply_bf,product(sum(premium,1),sum(ln(max(plays,1)),ln(max(sum(count,trend),1)))))^25</str>

<!-- Faceting defaults -->
<str name="facet.field">genre</str>
<int name="f.genre.facet.mincount">1</int>
<str name="f.genre.facet.method">enum</str>

<!-- grouping -->
<str name="group.field">id</str>
<str name="group.ngroups">true</str>
<int name="group.cache.percent">25</int>
</lst>
<lst name="defaults">
<str name="wt">json</str>
<str name="rows">10</str>
<str name="facet">off</str>
<str name="group">true</str>
<str name="fl">contributor_id,album_id,song_id</str>
<str name="bf">product(apply_bf,sum(ln(max(plays,1)),ln(max(sum(count,trend),1))))^25</str>
</lst>
<lst name="appends">
<!-- query filter for rights date -->
<str name="fq">start:[* TO NOW/DAY+1DAY] AND end:[NOW/DAY TO *]</str>
</lst>
</requestHandler>

None of the individual shards log any sort of error, however the server that is distributing the search logs the following stack trace fairly regular and returns a 500 error:

Nov 11, 2011 12:30:01 PM org.apache.solr.common.SolrException log
SEVERE: java.lang.NullPointerException
at org.apache.solr.response.JSONWriter.writeSolrDocument(JSONResponseWriter.java:320)
at org.apache.solr.response.TextResponseWriter.writeSolrDocumentList(TextResponseWriter.java:201)
at org.apache.solr.response.TextResponseWriter.writeVal(TextResponseWriter.java:169)
at org.apache.solr.response.JSONWriter.writeNamedListAsMapWithDups(JSONResponseWriter.java:174)
at org.apache.solr.response.JSONWriter.writeNamedList(JSONResponseWriter.java:290)
at org.apache.solr.response.TextResponseWriter.writeVal(TextResponseWriter.java:173)
at org.apache.solr.response.JSONWriter.writeArray(JSONResponseWriter.java:522)
at org.apache.solr.response.TextResponseWriter.writeVal(TextResponseWriter.java:175)
at org.apache.solr.response.JSONWriter.writeNamedListAsMapWithDups(JSONResponseWriter.java:174)
at org.apache.solr.response.JSONWriter.writeNamedList(JSONResponseWriter.java:290)
at org.apache.solr.response.TextResponseWriter.writeVal(TextResponseWriter.java:173)
at org.apache.solr.response.JSONWriter.writeNamedListAsMapWithDups(JSONResponseWriter.java:174)
at org.apache.solr.response.JSONWriter.writeNamedList(JSONResponseWriter.java:294)
at org.apache.solr.response.TextResponseWriter.writeVal(TextResponseWriter.java:173)
at org.apache.solr.response.JSONWriter.writeNamedListAsMapWithDups(JSONResponseWriter.java:174)
at org.apache.solr.response.JSONWriter.writeNamedList(JSONResponseWriter.java:290)
at org.apache.solr.response.JSONWriter.writeResponse(JSONResponseWriter.java:87)
at org.apache.solr.response.JSONResponseWriter.write(JSONResponseWriter.java:51)
at org.apache.solr.servlet.SolrDispatchFilter.writeResponse(SolrDispatchFilter.java:340)
at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:261)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:766)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)
at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)
at org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:114)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:945)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.jetty.bio.SocketConnector$Connection.run(SocketConnector.java:228)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)