Hi,
SOLR-295 https://issues.apache.org/jira/browse/SOLR-295 mentions boost
support for morelikethis and then seems to have been subsumed by
SOLR-281https://issues.apache.org/jira/browse/SOLR-281but I don't
think this got implemented. I've patched MoreLikeThisHandler to
support this. Here's a summary of the approach:
- Parse out mlt.qf parameters to get boosts in dismax like format
(existing code from DisMax param parse code used to produce a
MapString,Float)
- Iterate through mltquery terms, get boost by looking at field from
which mltquery term came, and multiply boost specified in map by existing
term boost.
- If mlt.boost=false, then you get the same boost values as in
map/mlt.qf parameters,
- If mlt.boost=true then you get normalized boost multiplied by specified
boost (which makes sense to me).
Patch attached.
Should I re-open either SOLR-281 or SOLR-295 (if I can) or create a new jira
ticket for this?
Thanks...Tom
Index: src/java/org/apache/solr/common/params/MoreLikeThisParams.java
===
--- src/java/org/apache/solr/common/params/MoreLikeThisParams.java (revision 663326)
+++ src/java/org/apache/solr/common/params/MoreLikeThisParams.java (working copy)
@@ -35,6 +35,7 @@
public final static String MAX_QUERY_TERMS = PREFIX + maxqt;
public final static String MAX_NUM_TOKENS_PARSED = PREFIX + maxntp;
public final static String BOOST = PREFIX + boost; // boost or not?
+ public final static String QF= PREFIX + qf; //boosting applied to nlt fields
// the /mlt request handler uses 'rows'
public final static String DOC_COUNT = PREFIX + count;
Index: src/java/org/apache/solr/handler/MoreLikeThisHandler.java
===
--- src/java/org/apache/solr/handler/MoreLikeThisHandler.java (revision 663326)
+++ src/java/org/apache/solr/handler/MoreLikeThisHandler.java (working copy)
@@ -23,8 +23,11 @@
import java.net.URL;
import java.util.ArrayList;
import java.util.Comparator;
+import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
+import java.util.Map;
+import java.util.Set;
import java.util.regex.Pattern;
import org.apache.lucene.document.Document;
@@ -37,6 +40,7 @@
import org.apache.lucene.search.similar.MoreLikeThis;
import org.apache.solr.common.SolrException;
import org.apache.solr.common.params.CommonParams;
+import org.apache.solr.common.params.DisMaxParams;
import org.apache.solr.common.params.FacetParams;
import org.apache.solr.common.params.MoreLikeThisParams;
import org.apache.solr.common.params.SolrParams;
@@ -51,7 +55,6 @@
import org.apache.solr.schema.IndexSchema;
import org.apache.solr.schema.SchemaField;
import org.apache.solr.search.DocIterator;
-import org.apache.solr.search.DocSet;
import org.apache.solr.search.DocList;
import org.apache.solr.search.DocListAndSet;
import org.apache.solr.search.QueryParsing;
@@ -231,6 +234,7 @@
final IndexReader reader;
final SchemaField uniqueKeyField;
final boolean needDocSet;
+MapString,Float boostFields;
Query mltquery; // expose this for debugging
@@ -260,12 +264,25 @@
mlt.setMaxQueryTerms( params.getInt(MoreLikeThisParams.MAX_QUERY_TERMS, MoreLikeThis.DEFAULT_MAX_QUERY_TERMS));
mlt.setMaxNumTokensParsed(params.getInt(MoreLikeThisParams.MAX_NUM_TOKENS_PARSED, MoreLikeThis.DEFAULT_MAX_NUM_TOKENS_PARSED));
mlt.setBoost(params.getBool(MoreLikeThisParams.BOOST, false ) );
+ boostFields = SolrPluginUtils.parseFieldBoosts(params.getParams(MoreLikeThisParams.QF));
}
+private void setBoosts(Query mltquery) {
+ List clauses = ((BooleanQuery)mltquery).clauses();
+ for( Object o : clauses ) {
+TermQuery q = (TermQuery)((BooleanClause)o).getQuery();
+Float b = this.boostFields.get(q.getTerm().field());
+if (b != null) {
+ q.setBoost(b*q.getBoost());
+}
+ }
+}
+
public DocListAndSet getMoreLikeThis( int id, int start, int rows, ListQuery filters, ListInterestingTerm terms, int flags ) throws IOException
{
Document doc = reader.document(id);
mltquery = mlt.like(id);
+ setBoosts(mltquery);
if( terms != null ) {
fillInterestingTermsFromMLTQuery( mltquery, terms );
}
@@ -289,6 +306,7 @@
public DocListAndSet getMoreLikeThis( Reader reader, int start, int rows, ListQuery filters, ListInterestingTerm terms, int flags ) throws IOException
{
mltquery = mlt.like(reader);
+ setBoosts(mltquery);
if( terms != null ) {
fillInterestingTermsFromMLTQuery( mltquery, terms );
}
