Merge pull request #29 from javamachr/master

Added DefaultMapper support to map only partial fields from result instead of whole source field.

Author: akonczak

src/main/java/org/springframework/data/elasticsearch/core/DefaultResultMapper.java

@@ -15,15 +15,25 @@
  */
 package org.springframework.data.elasticsearch.core;
 
+
 import org.elasticsearch.action.get.GetResponse;
 import org.elasticsearch.action.search.SearchResponse;
+import org.elasticsearch.common.base.Strings;
+import org.elasticsearch.common.jackson.core.JsonEncoding;
+import org.elasticsearch.common.jackson.core.JsonFactory;
+import org.elasticsearch.common.jackson.core.JsonGenerator;
 import org.elasticsearch.search.SearchHit;
+import org.elasticsearch.search.SearchHitField;
 import org.elasticsearch.search.facet.Facet;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.elasticsearch.core.facet.DefaultFacetMapper;
 import org.springframework.data.elasticsearch.core.facet.FacetResult;
 
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.charset.Charset;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 
 /**
@@ -45,7 +55,11 @@ public <T> FacetedPage<T> mapResults(SearchResponse response, Class<T> clazz, Pa
         List<T> results = new ArrayList<T>();
         for (SearchHit hit : response.getHits()) {
             if (hit != null) {
-                results.add(mapEntity(hit.sourceAsString(), clazz));
+                if (!Strings.isNullOrEmpty(hit.sourceAsString())) {
+                    results.add(mapEntity(hit.sourceAsString(), clazz));
+                } else {
+                    results.add(mapEntity(hit.getFields().values(), clazz));
+                }
             }
         }
         List<FacetResult> facets = new ArrayList<FacetResult>();
@@ -61,6 +75,35 @@ public <T> FacetedPage<T> mapResults(SearchResponse response, Class<T> clazz, Pa
         return new FacetedPageImpl<T>(results, pageable, totalHits, facets);
     }
 
+    private <T> T mapEntity(Collection<SearchHitField> values, Class<T> clazz) {
+            return mapEntity(buildJSONFromFields(values), clazz);
+    }
+
+    private String buildJSONFromFields(Collection<SearchHitField> values) {
+        JsonFactory nodeFactory = new JsonFactory();
+        try {
+            ByteArrayOutputStream stream = new ByteArrayOutputStream();
+            JsonGenerator generator = nodeFactory.createGenerator(stream, JsonEncoding.UTF8);
+            generator.writeStartObject();
+            for (SearchHitField value : values) {
+                if (value.getValues().size() > 1) {
+                    generator.writeArrayFieldStart(value.getName());
+                    for (Object val : value.getValues()) {
+                        generator.writeObject(val);
+                    }
+                    generator.writeEndArray();
+                } else {
+                    generator.writeObjectField(value.getName(), value.getValue());
+                }
+            }
+            generator.writeEndObject();
+            generator.flush();
+            return new String(stream.toByteArray(), Charset.forName("UTF-8"));
+        } catch (IOException e) {
+            return null;
+        }
+    }
+
     @Override
     public <T> T mapResult(GetResponse response, Class<T> clazz) {
         return mapEntity(response.getSourceAsString(),clazz);

src/test/java/org/springframework/data/elasticsearch/core/DefaultResultMapperTests.java

@@ -3,14 +3,22 @@
 import org.apache.commons.collections.iterators.ArrayIterator;
 import org.elasticsearch.action.get.GetResponse;
 import org.elasticsearch.action.search.SearchResponse;
+import org.elasticsearch.index.get.GetField;
 import org.elasticsearch.search.SearchHit;
+import org.elasticsearch.search.SearchHitField;
 import org.elasticsearch.search.SearchHits;
+import org.elasticsearch.search.internal.InternalSearchHitField;
 import org.junit.Before;
 import org.junit.Test;
 import org.mockito.Mock;
+import org.mockito.Mockito;
 import org.mockito.MockitoAnnotations;
 import org.springframework.data.elasticsearch.Car;
 
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.junit.Assert.assertThat;
@@ -51,6 +59,24 @@ public void shouldMapSearchRequestToPage() {
         assertThat(page.getContent().get(0).getName(), is("Ford"));
     }
 
+    @Test
+    public void shouldMapPartialSearchRequestToObject() {
+        //Given
+        SearchHit[] hits = {createCarPartialHit("Ford", "Grat"), createCarPartialHit("BMW", "Arrow")};
+        SearchHits searchHits = mock(SearchHits.class);
+        when(searchHits.totalHits()).thenReturn(2L);
+        when(searchHits.iterator()).thenReturn(new ArrayIterator(hits));
+        when(response.getHits()).thenReturn(searchHits);
+
+        //When
+        FacetedPage<Car> page = resultMapper.mapResults(response, Car.class, null);
+
+        //Then
+        assertThat(page.hasContent(), is(true));
+        assertThat(page.getTotalElements(), is(2L));
+        assertThat(page.getContent().get(0).getName(), is("Ford"));
+    }
+
     @Test
     public void shouldMapGetRequestToObject() {
         //Given
@@ -72,6 +98,13 @@ private SearchHit createCarHit(String name, String model) {
         return hit;
     }
 
+    private SearchHit createCarPartialHit(String name, String model) {
+        SearchHit hit = mock(SearchHit.class);
+        when(hit.sourceAsString()).thenReturn(null);
+        when(hit.getFields()).thenReturn(createCarFields(name, model));
+        return hit;
+    }
+
     private String createJsonCar(String name, String model) {
         final String q = "\"";
         StringBuffer sb = new StringBuffer();
@@ -80,4 +113,11 @@ private String createJsonCar(String name, String model) {
         return sb.toString();
     }
 
+    private Map<String, SearchHitField> createCarFields(String name, String model) {
+        Map<String, SearchHitField> result = new HashMap<String, SearchHitField>();
+        result.put("name", new InternalSearchHitField("name", Arrays.<Object>asList(name)));
+        result.put("model", new InternalSearchHitField("model", Arrays.<Object>asList(model)));
+        return result;
+    }
+
 }