Scripts: exposed _uid, _id and _type fields as stored fields (_fields notation)

The _uid field wasn't available in a script despite it's always stored. Made it available and made available also _id and _type fields that are deducted from it.

Closes #6406

src/main/java/org/elasticsearch/index/fieldvisitor/FieldsVisitor.java

@@ -136,7 +136,7 @@ public abstract class FieldsVisitor extends StoredFieldVisitor {
         uid = null;
     }
 
-    private void addValue(String name, Object value) {
+    void addValue(String name, Object value) {
         if (fieldsValues == null) {
             fieldsValues = newHashMap();
         }

src/main/java/org/elasticsearch/index/fieldvisitor/SingleFieldsVisitor.java

@@ -20,6 +20,9 @@ package org.elasticsearch.index.fieldvisitor;
 
 import org.apache.lucene.index.FieldInfo;
 import org.elasticsearch.index.mapper.FieldMapper;
+import org.elasticsearch.index.mapper.internal.IdFieldMapper;
+import org.elasticsearch.index.mapper.internal.TypeFieldMapper;
+import org.elasticsearch.index.mapper.internal.UidFieldMapper;
 
 import java.io.IOException;
 import java.util.List;
@@ -36,12 +39,15 @@ public class SingleFieldsVisitor extends FieldsVisitor {
 
     @Override
     public Status needsField(FieldInfo fieldInfo) throws IOException {
-        // TODO we can potentially skip if we processed a field, the question is if it works for multi valued fields
         if (fieldInfo.name.equals(field)) {
             return Status.YES;
-        } else {
-            return Status.NO;
         }
+        if (fieldInfo.name.equals(UidFieldMapper.NAME)) {
+            if (TypeFieldMapper.NAME.equals(field) || IdFieldMapper.NAME.equals(field)) {
+                return Status.YES;
+            }
+        }
+        return Status.NO;
     }
 
     public void reset(String field) {
@@ -50,6 +56,14 @@ public class SingleFieldsVisitor extends FieldsVisitor {
     }
 
     public void postProcess(FieldMapper mapper) {
+        if (uid != null) {
+            switch (field) {
+                case UidFieldMapper.NAME: addValue(field, uid.toString());
+                case IdFieldMapper.NAME: addValue(field, uid.id());
+                case TypeFieldMapper.NAME: addValue(field, uid.type());
+            }
+        }
+
         if (fieldsValues == null) {
             return;
         }

src/test/java/org/elasticsearch/search/fields/SearchFieldsTests.java

@@ -19,6 +19,7 @@
 
 package org.elasticsearch.search.fields;
 
+import org.elasticsearch.action.index.IndexRequestBuilder;
 import org.elasticsearch.action.search.SearchRequestBuilder;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.common.Base64;
@@ -147,14 +148,17 @@ public class SearchFieldsTests extends ElasticsearchIntegrationTest {
         assertThat(response.getHits().totalHits(), equalTo(3l));
         assertThat(response.getHits().getAt(0).isSourceEmpty(), equalTo(true));
         assertThat(response.getHits().getAt(0).id(), equalTo("1"));
+        assertThat(response.getHits().getAt(0).fields().size(), equalTo(3));
         assertThat((Double) response.getHits().getAt(0).fields().get("sNum1").values().get(0), equalTo(1.0));
         assertThat((Double) response.getHits().getAt(0).fields().get("sNum1_field").values().get(0), equalTo(1.0));
         assertThat((Long) response.getHits().getAt(0).fields().get("date1").values().get(0), equalTo(0l));
         assertThat(response.getHits().getAt(1).id(), equalTo("2"));
+        assertThat(response.getHits().getAt(1).fields().size(), equalTo(3));
         assertThat((Double) response.getHits().getAt(1).fields().get("sNum1").values().get(0), equalTo(2.0));
         assertThat((Double) response.getHits().getAt(1).fields().get("sNum1_field").values().get(0), equalTo(2.0));
         assertThat((Long) response.getHits().getAt(1).fields().get("date1").values().get(0), equalTo(25000l));
         assertThat(response.getHits().getAt(2).id(), equalTo("3"));
+        assertThat(response.getHits().getAt(2).fields().size(), equalTo(3));
         assertThat((Double) response.getHits().getAt(2).fields().get("sNum1").values().get(0), equalTo(3.0));
         assertThat((Double) response.getHits().getAt(2).fields().get("sNum1_field").values().get(0), equalTo(3.0));
         assertThat((Long) response.getHits().getAt(2).fields().get("date1").values().get(0), equalTo(120000l));
@@ -169,13 +173,86 @@ public class SearchFieldsTests extends ElasticsearchIntegrationTest {
 
         assertThat(response.getHits().totalHits(), equalTo(3l));
         assertThat(response.getHits().getAt(0).id(), equalTo("1"));
+        assertThat(response.getHits().getAt(0).fields().size(), equalTo(1));
         assertThat((Double) response.getHits().getAt(0).fields().get("sNum1").values().get(0), equalTo(2.0));
         assertThat(response.getHits().getAt(1).id(), equalTo("2"));
+        assertThat(response.getHits().getAt(1).fields().size(), equalTo(1));
         assertThat((Double) response.getHits().getAt(1).fields().get("sNum1").values().get(0), equalTo(4.0));
         assertThat(response.getHits().getAt(2).id(), equalTo("3"));
+        assertThat(response.getHits().getAt(2).fields().size(), equalTo(1));
         assertThat((Double) response.getHits().getAt(2).fields().get("sNum1").values().get(0), equalTo(6.0));
     }
 
+    @Test
+    public void testUidBasedScriptFields() throws Exception {
+        createIndex("test");
+        ensureYellow();
+
+        int numDocs = randomIntBetween(1, 30);
+        IndexRequestBuilder[] indexRequestBuilders = new IndexRequestBuilder[numDocs];
+        for (int i = 0; i < numDocs; i++) {
+            indexRequestBuilders[i] = client().prepareIndex("test", "type1", Integer.toString(i))
+                    .setSource(jsonBuilder().startObject().field("num1", i).endObject());
+        }
+        indexRandom(true, indexRequestBuilders);
+
+        SearchResponse response = client().prepareSearch()
+                .setQuery(matchAllQuery()).addSort("num1", SortOrder.ASC).setSize(numDocs)
+                .addScriptField("uid", "_fields._uid.value").get();
+
+        assertNoFailures(response);
+
+        assertThat(response.getHits().totalHits(), equalTo((long)numDocs));
+        for (int i = 0; i < numDocs; i++) {
+            assertThat(response.getHits().getAt(i).id(), equalTo(Integer.toString(i)));
+            assertThat(response.getHits().getAt(i).fields().size(), equalTo(1));
+            assertThat((String)response.getHits().getAt(i).fields().get("uid").value(), equalTo("type1#" + Integer.toString(i)));
+        }
+
+        response = client().prepareSearch()
+                .setQuery(matchAllQuery()).addSort("num1", SortOrder.ASC).setSize(numDocs)
+                .addScriptField("id", "_fields._id.value").get();
+
+        assertNoFailures(response);
+
+        assertThat(response.getHits().totalHits(), equalTo((long)numDocs));
+        for (int i = 0; i < numDocs; i++) {
+            assertThat(response.getHits().getAt(i).id(), equalTo(Integer.toString(i)));
+            assertThat(response.getHits().getAt(i).fields().size(), equalTo(1));
+            assertThat((String)response.getHits().getAt(i).fields().get("id").value(), equalTo(Integer.toString(i)));
+        }
+
+        response = client().prepareSearch()
+                .setQuery(matchAllQuery()).addSort("num1", SortOrder.ASC).setSize(numDocs)
+                .addScriptField("type", "_fields._type.value").get();
+
+        assertNoFailures(response);
+
+        assertThat(response.getHits().totalHits(), equalTo((long)numDocs));
+        for (int i = 0; i < numDocs; i++) {
+            assertThat(response.getHits().getAt(i).id(), equalTo(Integer.toString(i)));
+            assertThat(response.getHits().getAt(i).fields().size(), equalTo(1));
+            assertThat((String)response.getHits().getAt(i).fields().get("type").value(), equalTo("type1"));
+        }
+
+        response = client().prepareSearch()
+                .setQuery(matchAllQuery()).addSort("num1", SortOrder.ASC).setSize(numDocs)
+                .addScriptField("id", "_fields._id.value")
+                .addScriptField("uid", "_fields._uid.value")
+                .addScriptField("type", "_fields._type.value").get();
+
+        assertNoFailures(response);
+
+        assertThat(response.getHits().totalHits(), equalTo((long)numDocs));
+        for (int i = 0; i < numDocs; i++) {
+            assertThat(response.getHits().getAt(i).id(), equalTo(Integer.toString(i)));
+            assertThat(response.getHits().getAt(i).fields().size(), equalTo(3));
+            assertThat((String)response.getHits().getAt(i).fields().get("uid").value(), equalTo("type1#" + Integer.toString(i)));
+            assertThat((String)response.getHits().getAt(i).fields().get("type").value(), equalTo("type1"));
+            assertThat((String)response.getHits().getAt(i).fields().get("id").value(), equalTo(Integer.toString(i)));
+        }
+    }
+
     @Test
     public void testScriptFieldUsingSource() throws Exception {
         createIndex("test");
@@ -213,12 +290,12 @@ public class SearchFieldsTests extends ElasticsearchIntegrationTest {
         assertThat(sObj2Arr2.get(0).toString(), equalTo("arr_value1"));
         assertThat(sObj2Arr2.get(1).toString(), equalTo("arr_value2"));
 
-        sObj2Arr2 = (List) response.getHits().getAt(0).field("s_obj2_arr2").value();
+        sObj2Arr2 = response.getHits().getAt(0).field("s_obj2_arr2").value();
         assertThat(sObj2Arr2.size(), equalTo(2));
         assertThat(sObj2Arr2.get(0).toString(), equalTo("arr_value1"));
         assertThat(sObj2Arr2.get(1).toString(), equalTo("arr_value2"));
 
-        List sObj2Arr3 = (List) response.getHits().getAt(0).field("s_arr3").value();
+        List sObj2Arr3 = response.getHits().getAt(0).field("s_arr3").value();
         assertThat(((Map) sObj2Arr3.get(0)).get("arr3_field1").toString(), equalTo("arr3_value1"));
     }