SOLR-6311: SearchHandler should use path when no qt or shard.qt parameter is specified

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1659694 13f79535-47bb-0310-9956-ffa450edef68

solr/CHANGES.txt

@@ -155,6 +155,10 @@ Other Changes
 
 * SOLR-7103: Remove unused method params in faceting code. (shalin)
 
+* SOLR-6311: When performing distributed queries, SearchHandler should use path
+  when no qt or shard.qt parameter is specified; fix also resolves SOLR-4479.
+  (Steve Molloy, Timothy Potter)
+
 ==================  5.0.0 ==================
 
 Consult the LUCENE_CHANGES.txt file for additional, low level, changes in this release.

solr/core/src/java/org/apache/solr/handler/component/SearchHandler.java

@@ -18,6 +18,7 @@
 package org.apache.solr.handler.component;
 
 import org.apache.lucene.index.ExitableDirectoryReader;
+import org.apache.lucene.util.Version;
 import org.apache.solr.client.solrj.SolrServerException;
 import org.apache.solr.common.SolrDocumentList;
 import org.apache.solr.common.SolrException;
@@ -306,10 +307,21 @@ public class SearchHandler extends RequestHandlerBase implements SolrCoreAware ,
                 params.set("NOW", Long.toString(rb.requestInfo.getNOW().getTime()));
               }
               String shardQt = params.get(ShardParams.SHARDS_QT);
-              if (shardQt == null) {
+              if (shardQt != null) {
-                params.remove(CommonParams.QT);
-              } else {
                 params.set(CommonParams.QT, shardQt);
+              } else {
+                // for distributed queries that don't include shards.qt, use the original path
+                // as the default but operators need to update their luceneMatchVersion to enable
+                // this behavior since it did not work this way prior to 5.1
+                if (req.getCore().getSolrConfig().luceneMatchVersion.onOrAfter(Version.LUCENE_5_1_0)) {
+                  String reqPath = (String)req.getContext().get("path");
+                  if (!"/select".equals(reqPath)) {
+                    params.set(CommonParams.QT, reqPath);
+                  } // else if path is /select, then the qt gets passed thru if set
+                } else {
+                  // this is the pre-5.1 behavior, which translates to sending the shard request to /select
+                  params.remove(CommonParams.QT);
+                }
               }
               shardHandler1.submit(sreq, shard, params);
             }

solr/core/src/test/org/apache/solr/handler/component/TermVectorComponentDistributedTest.java

@@ -123,10 +123,8 @@ public class TermVectorComponentDistributedTest extends BaseDistributedSearchTes
     final String tv = "tvrh";
 
     for (String q : new String[] {"id:0", "id:7", "id:[3 TO 6]", "*:*"}) {
-
       query("sort","id desc",
             "qt",tv, 
-            "shards.qt",tv,
             "q", q,
             TermVectorComponent.COMPONENT_NAME, "true", 
             TermVectorParams.TF, "true");
@@ -134,7 +132,6 @@ public class TermVectorComponentDistributedTest extends BaseDistributedSearchTes
       // tv.fl diff from fl
       query("sort", "id asc",
             "qt",tv, 
-            "shards.qt",tv,
             "q", q,
             "fl", "*,score",
             "tv.fl", "test_basictv,test_offtv",
@@ -144,7 +141,6 @@ public class TermVectorComponentDistributedTest extends BaseDistributedSearchTes
       // multi-valued tv.fl 
       query("sort", "id asc",
             "qt",tv, 
-            "shards.qt",tv,
             "q", q,
             "fl", "*,score",
             "tv.fl", "test_basictv",
@@ -154,7 +150,6 @@ public class TermVectorComponentDistributedTest extends BaseDistributedSearchTes
       // re-use fl glob
       query("sort", "id desc",
             "qt",tv, 
-            "shards.qt",tv,
             "q", q,
             "fl", "*,score",
             TermVectorComponent.COMPONENT_NAME, "true", 
@@ -162,7 +157,6 @@ public class TermVectorComponentDistributedTest extends BaseDistributedSearchTes
       // re-use fl, ignore things we can't handle
       query("sort", "id desc",
             "qt",tv, 
-            "shards.qt",tv,
             "q", q,
             "fl", "score,test_basictv,[docid],test_postv,val:sum(3,4)",
             TermVectorComponent.COMPONENT_NAME, "true", 
@@ -171,7 +165,6 @@ public class TermVectorComponentDistributedTest extends BaseDistributedSearchTes
       // re-use (multi-valued) fl, ignore things we can't handle
       query("sort", "id desc",
             "qt",tv, 
-            "shards.qt",tv,
             "q", q,
             "fl", "score,test_basictv",
             "fl", "[docid],test_postv,val:sum(3,4)",
@@ -182,7 +175,6 @@ public class TermVectorComponentDistributedTest extends BaseDistributedSearchTes
     
       query("sort", "id asc",
             "qt",tv, 
-            "shards.qt",tv,
             "q", q,
             TermVectorComponent.COMPONENT_NAME, "true",
             TermVectorParams.TF, "true", 
@@ -193,7 +185,6 @@ public class TermVectorComponentDistributedTest extends BaseDistributedSearchTes
     
       query("sort", "id desc",
             "qt",tv, 
-            "shards.qt",tv,
             "q", q,
             TermVectorComponent.COMPONENT_NAME, "true",
             TermVectorParams.ALL, "true");
@@ -202,7 +193,6 @@ public class TermVectorComponentDistributedTest extends BaseDistributedSearchTes
 
       query("sort", "id desc",
             "qt",tv, 
-            "shards.qt",tv,
             "q", q,
             TermVectorComponent.COMPONENT_NAME, "true",
             TermVectorParams.TF, "true",