better tests for null mappings

Author: romseygeek

rest-api-spec/src/main/resources/rest-api-spec/test/indices.get_field_mapping/20_missing_field.yml

@@ -17,3 +17,4 @@
         fields: not_existent
 
   - match: { 'test_index.mappings': {}}
+

server/src/main/java/org/elasticsearch/action/admin/indices/mapping/get/GetFieldMappingsResponse.java

@@ -105,7 +105,7 @@ public FieldMappingMetaData fieldMappings(String index, String field) {
 
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
-                builder.startObject();
+        builder.startObject();
         for (Map.Entry<String, Map<String, FieldMappingMetaData>> indexEntry : mappings.entrySet()) {
             builder.startObject(indexEntry.getKey());
             builder.startObject(MAPPINGS.getPreferredName());
@@ -125,9 +125,11 @@ private void addFieldMappingsToBuilder(XContentBuilder builder,
                                            Params params,
                                            Map<String, FieldMappingMetaData> mappings) throws IOException {
         for (Map.Entry<String, FieldMappingMetaData> fieldEntry : mappings.entrySet()) {
-            builder.startObject(fieldEntry.getKey());
-            fieldEntry.getValue().toXContent(builder, params);
-            builder.endObject();
+            if (fieldEntry.getValue().isNull() == false) {
+                builder.startObject(fieldEntry.getKey());
+                fieldEntry.getValue().toXContent(builder, params);
+                builder.endObject();
+            }
         }
     }
 

server/src/main/java/org/elasticsearch/rest/action/admin/indices/RestGetFieldMappingAction.java

@@ -67,12 +67,13 @@ public RestChannelConsumer prepareRequest(final RestRequest request, final NodeC
                     @Override
                     public RestResponse buildResponse(GetFieldMappingsResponse response, XContentBuilder builder) throws Exception {
                         Map<String, Map<String, FieldMappingMetaData>> mappingsByIndex = response.mappings();
-                        
+
                         RestStatus status = OK;
                         if (mappingsByIndex.isEmpty() && fields.length > 0) {
                             status = NOT_FOUND;
                         }
                         response.toXContent(builder, request);
+                        logger.warn(Strings.toString(response));
                         return new BytesRestResponse(status, builder);
                     }
                 });

server/src/test/java/org/elasticsearch/action/admin/indices/mapping/get/GetFieldMappingsResponseTests.java

@@ -20,6 +20,7 @@
 package org.elasticsearch.action.admin.indices.mapping.get;
 
 import org.elasticsearch.action.admin.indices.mapping.get.GetFieldMappingsResponse.FieldMappingMetaData;
+import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.bytes.BytesArray;
 import org.elasticsearch.common.io.stream.BytesStreamOutput;
 import org.elasticsearch.common.io.stream.StreamInput;
@@ -31,6 +32,8 @@
 import java.util.HashMap;
 import java.util.Map;
 
+import static org.hamcrest.CoreMatchers.containsString;
+
 public class GetFieldMappingsResponseTests extends AbstractWireSerializingTestCase<GetFieldMappingsResponse> {
 
     public void testManualSerialization() throws IOException {
@@ -50,6 +53,28 @@ public void testManualSerialization() throws IOException {
         }
     }
 
+    public void testNullFieldMappingToXContent() {
+        Map<String, Map<String, FieldMappingMetaData>> mappings = new HashMap<>();
+        mappings.put("index", Collections.singletonMap("field", FieldMappingMetaData.NULL));
+        GetFieldMappingsResponse response = new GetFieldMappingsResponse(mappings);
+        assertEquals("{\"index\":{\"mappings\":{}}}", Strings.toString(response));
+    }
+
+    public void testMixedNullAndPresentFieldMappingToXContent() {
+        Map<String, Map<String, FieldMappingMetaData>> mappings = new HashMap<>();
+        mappings.put("index", Map.of("field", FieldMappingMetaData.NULL,
+            "field1", new FieldMappingMetaData("field1", new BytesArray("{\"type\":\"string\"}"))));
+        mappings.put("index2", Map.of("field", new FieldMappingMetaData("field", new BytesArray("{}"))));
+        mappings.put("index3", Map.of("field", FieldMappingMetaData.NULL));
+        GetFieldMappingsResponse response = new GetFieldMappingsResponse(mappings);
+        String respAsString = Strings.toString(response);
+        assertThat(respAsString, containsString("\"index3\":{\"mappings\":{}}"));
+        assertThat(respAsString,
+            containsString("\"index\":{\"mappings\":{\"field1\":{\"full_name\":\"field1\",\"mapping\":{\"type\":\"string\"}}}}"));
+        assertThat(respAsString,
+            containsString("\"index2\":{\"mappings\":{\"field\":{\"full_name\":\"field\",\"mapping\":{}}}}"));
+    }
+
     @Override
     protected GetFieldMappingsResponse createTestInstance() {
         return new GetFieldMappingsResponse(randomMapping());