SOLR-3413: support multiple copies in return fields

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1330568 13f79535-47bb-0310-9956-ffa450edef68

solr/core/src/java/org/apache/solr/response/transform/RenameFieldTransformer.java

@@ -26,37 +26,30 @@ import org.apache.solr.request.SolrQueryRequest;
  *
  * @since solr 4.0
  */
-public class RenameFieldsTransformer extends DocTransformer
+public class RenameFieldTransformer extends DocTransformer
 {
-  final NamedList<String> rename;
+  final String from;
+  final String to;
+  final boolean copy;
 
-  public RenameFieldsTransformer( NamedList<String> rename )
+  public RenameFieldTransformer( String from, String to, boolean copy )
   {
-    this.rename = rename;
+    this.from = from;
+    this.to = to;
+    this.copy = copy;
   }
 
   @Override
   public String getName()
   {
-    StringBuilder str = new StringBuilder();
-    str.append( "Rename[" );
-    for( int i=0; i< rename.size(); i++ ) {
-      if( i > 0 ) {
-        str.append( "," );
-      }
-      str.append( rename.getName(i) ).append( ">>" ).append( rename.getVal( i ) );
-    }
-    str.append( "]" );
-    return str.toString();
+    return "Rename["+from+">>"+to+"]";
   }
 
   @Override
   public void transform(SolrDocument doc, int docid) {
-    for( int i=0; i<rename.size(); i++ ) {
-      Object v = doc.remove( rename.getName(i) );
-      if( v != null ) {
-        doc.setField(rename.getVal(i), v);
-      }
+    Object v = (copy)?doc.get(from) : doc.remove( from );
+    if( v != null ) {
+      doc.setField(to, v);
     }
   }
 }

solr/core/src/java/org/apache/solr/search/ReturnFields.java

@@ -32,7 +32,7 @@ import org.apache.solr.common.util.NamedList;
 import org.apache.solr.request.SolrQueryRequest;
 import org.apache.solr.response.transform.DocTransformer;
 import org.apache.solr.response.transform.DocTransformers;
-import org.apache.solr.response.transform.RenameFieldsTransformer;
+import org.apache.solr.response.transform.RenameFieldTransformer;
 import org.apache.solr.response.transform.ScoreAugmenter;
 import org.apache.solr.response.transform.TransformerFactory;
 import org.apache.solr.response.transform.ValueSourceAugmenter;
@@ -61,6 +61,9 @@ public class ReturnFields
   // Field names that are OK to include in the response.
   // This will include pseudo fields, lucene fields, and matching globs
   private Set<String> okFieldNames = new HashSet<String>(); 
+
+  // The list of explicitly requested fields
+  private Set<String> reqFieldNames = null;
   
   private DocTransformer transformer;
   private boolean _wantsScore = false;
@@ -111,11 +114,24 @@ public class ReturnFields
     for (String fieldList : fl) {
       add(fieldList,rename,augmenters,req);
     }
-    if( rename.size() > 0 ) {
-      for( int i=0; i<rename.size(); i++ ) {
-        okFieldNames.add( rename.getVal(i) );
+    for( int i=0; i<rename.size(); i++ ) {
+      String from = rename.getName(i);
+      String to = rename.getVal(i);
+      okFieldNames.add( to );
+      boolean copy = (reqFieldNames!=null && reqFieldNames.contains(from));
+      if(!copy) {
+        // Check that subsequent copy/rename requests have the field they need to copy
+        for(int j=i+1; j<rename.size(); j++) {
+          if(from.equals(rename.getName(j))) {
+            rename.setName(j, to); // copy from the current target
+            if(reqFieldNames==null) {
+              reqFieldNames = new HashSet<String>();
+            }
+            reqFieldNames.add(to); // don't rename our current target
+          }
+        }
       }
-      augmenters.addTransformer( new RenameFieldsTransformer( rename ) );
+      augmenters.addTransformer( new RenameFieldTransformer( from, to, copy ) );     
     }
 
     if( !_wantsAllFields ) {
@@ -348,13 +364,21 @@ public class ReturnFields
 
   private void addField( String field, String key, DocTransformers augmenters, SolrQueryRequest req )
   {
-    String disp = (key==null) ? field : key;
+    if(key==null) {
+      if(reqFieldNames==null) {
+        reqFieldNames = new HashSet<String>();
+      }
+      reqFieldNames.add(field);
+    }
+    
     fields.add(field); // need to put in the map to maintain order for things like CSVResponseWriter
     okFieldNames.add( field );
     okFieldNames.add( key );
     // a valid field name
     if(SCORE.equals(field)) {
       _wantsScore = true;
+
+      String disp = (key==null) ? field : key;
       augmenters.addTransformer( new ScoreAugmenter( disp ) );
     }
   }

solr/core/src/test/org/apache/solr/search/ReturnFieldsTest.java

@@ -18,6 +18,8 @@
 package org.apache.solr.search;
 
 import org.apache.solr.SolrTestCaseJ4;
+import org.apache.solr.common.params.CommonParams;
+import org.apache.solr.request.SolrQueryRequest;
 import org.apache.solr.response.transform.*;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -49,6 +51,46 @@ public class ReturnFieldsTest extends SolrTestCaseJ4 {
     assertU(commit());
   }
 
+  @Test
+  public void testCopyRename() throws Exception {
+
+    // original
+    assertQ(req("q","id:1", "fl","id")
+        ,"//*[@numFound='1'] "
+        ,"*[count(//doc/str)=1] "
+        ,"*//doc[1]/str[1][.='1'] "
+        );
+    
+    // rename
+    assertQ(req("q","id:1", "fl","xxx:id")
+        ,"//*[@numFound='1'] "
+        ,"*[count(//doc/str)=1] "
+        ,"*//doc[1]/str[1][.='1'] "
+        );
+
+    // original and copy
+    assertQ(req("q","id:1", "fl","id,xxx:id")
+        ,"//*[@numFound='1'] "
+        ,"*[count(//doc/str)=2] "
+        ,"*//doc[1]/str[1][.='1'] "
+        ,"*//doc[1]/str[2][.='1'] "
+        );
+    assertQ(req("q","id:1", "fl","xxx:id,id")
+        ,"//*[@numFound='1'] "
+        ,"*[count(//doc/str)=2] "
+        ,"*//doc[1]/str[1][.='1'] "
+        ,"*//doc[1]/str[2][.='1'] "
+        );
+
+    // two copies
+    assertQ(req("q","id:1", "fl","xxx:id,yyy:id")
+        ,"//*[@numFound='1'] "
+        ,"*[count(//doc/str)=2] "
+        ,"*//doc[1]/str[1][.='1'] "
+        ,"*//doc[1]/str[2][.='1'] "
+        );
+  }
+
   @Test
   public void testSeparators() {
     ReturnFields rf = new ReturnFields( req("fl", "id name test subject score") );
@@ -202,7 +244,6 @@ public class ReturnFieldsTest extends SolrTestCaseJ4 {
     assertTrue(rf.wantsField("newSubject"));
     assertFalse(rf.wantsField("xxx"));
     assertFalse(rf.wantsAllFields());
-    assertTrue( rf.getTransformer() instanceof RenameFieldsTransformer);
 
     rf = new ReturnFields( req("fl", "newId:id newName:name newTest:test newSubject:subject score") );
     assertTrue(rf.wantsField("id"));
@@ -216,7 +257,7 @@ public class ReturnFieldsTest extends SolrTestCaseJ4 {
     assertFalse(rf.wantsField("xxx"));
     assertFalse(rf.wantsAllFields());
     assertTrue( rf.getTransformer() instanceof DocTransformers);
-    assertEquals(2, ((DocTransformers)rf.getTransformer()).size());
+    assertEquals(5, ((DocTransformers)rf.getTransformer()).size());  // 4 rename and score
   }
 
   // hyphens in field names are not supported in all contexts, but we wanted

solr/solrj/src/test/org/apache/solr/client/solrj/StartSolrJetty.java

@@ -31,9 +31,6 @@ public class StartSolrJetty
   {
     //System.setProperty("solr.solr.home", "../../../example/solr");
 
-    javax.servlet.FilterRegistration xx;
-    
-    
     Server server = new Server();
     SocketConnector connector = new SocketConnector();
     // Set some timeout options to make debugging easier.