collapse filter query

[sara hajili]

hi all
i have a MLT query and i wanna to use collapse filter query.
and i wanna to use collapse expand nullPolicy.
in this way when i used it :
{!collapse field=original_post_id nullPolicy=expand}
i got my appropriate result .
(in solr web UI)

but in regular search handler "/select",when i used
{!collapse field=original_post_id nullPolicy=expand}
i got error:

{
  "responseHeader":{
    "status":500,
    "QTime":2,
    "params":{
      "q":"*:*",
      "indent":"true",
      "fq":"{!collapse field=original_post_id nullPolicy=expand}",
      "wt":"json"}},
  "error":{
    "trace":"java.lang.NullPointerException\n\tat
org.apache.solr.search.CollapsingQParserPlugin$IntScoreCollector.finish(CollapsingQParserPlugin.java:763)\n\tat
org.apache.solr.search.SolrIndexSearcher.buildAndRunCollectorChain(SolrIndexSearcher.java:211)\n\tat
org.apache.solr.search.SolrIndexSearcher.getDocListNC(SolrIndexSearcher.java:1678)\n\tat
org.apache.solr.search.SolrIndexSearcher.getDocListC(SolrIndexSearcher.java:1497)\n\tat
org.apache.solr.search.SolrIndexSearcher.search(SolrIndexSearcher.java:555)\n\tat
org.apache.solr.handler.component.QueryComponent.process(QueryComponent.java:522)\n\tat
org.apache.solr.handler.component.SearchHandler.handleRequestBody(SearchHandler.java:277)\n\tat
org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:143)\n\tat
org.apache.solr.core.SolrCore.execute(SolrCore.java:2068)\n\tat
org.apache.solr.servlet.HttpSolrCall.execute(HttpSolrCall.java:669)\n\tat
org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:462)\n\tat
org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:214)\n\tat
org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:179)\n\tat
org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)\n\tat
org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585)\n\tat
org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)\n\tat
org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577)\n\tat
org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)\n\tat
org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)\n\tat
org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)\n\tat
org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)\n\tat
org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)\n\tat
org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)\n\tat
org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:215)\n\tat
org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:110)\n\tat
org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)\n\tat
org.eclipse.jetty.server.Server.handle(Server.java:499)\n\tat
org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310)\n\tat
org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)\n\tat
org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)\n\tat
org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)\n\tat
org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)\n\tat
java.lang.Thread.run(Thread.java:745)\n",
    "code":500}}


but if i change nullpolicy to ignore or collapse

no error happened.


and i wondered when i used pysolr to create  a more like this query

i get above error again.

so it seems nullpolicy=expand work me just in more like this query in
solr web UI!!!!

and my question is how to solve my problem to use nullpolicy=expand in pysolr?

tnx