Add Cluster Put Settings API to the high level REST client (#28633)

Relates to #27205

client/rest-high-level/src/main/java/org/elasticsearch/client/ClusterClient.java

@@ -0,0 +1,66 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.client;
+
+import org.apache.http.Header;
+import org.elasticsearch.action.ActionListener;
+import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsRequest;
+import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsResponse;
+
+import java.io.IOException;
+
+import static java.util.Collections.emptySet;
+
+/**
+ * A wrapper for the {@link RestHighLevelClient} that provides methods for accessing the Cluster API.
+ * <p>
+ * See <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/cluster.html">Cluster API on elastic.co</a>
+ */
+public final class ClusterClient {
+    private final RestHighLevelClient restHighLevelClient;
+
+    ClusterClient(RestHighLevelClient restHighLevelClient) {
+        this.restHighLevelClient = restHighLevelClient;
+    }
+
+    /**
+     * Updates cluster wide specific settings using the Cluster Update Settings API
+     * <p>
+     * See <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-update-settings.html"> Cluster Update Settings
+     * API on elastic.co</a>
+     */
+    public ClusterUpdateSettingsResponse putSettings(ClusterUpdateSettingsRequest clusterUpdateSettingsRequest, Header... headers)
+            throws IOException {
+        return restHighLevelClient.performRequestAndParseEntity(clusterUpdateSettingsRequest, Request::clusterPutSettings,
+                ClusterUpdateSettingsResponse::fromXContent, emptySet(), headers);
+    }
+
+    /**
+     * Asynchronously updates cluster wide specific settings using the Cluster Update Settings API
+     * <p>
+     * See <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-update-settings.html"> Cluster Update Settings
+     * API on elastic.co</a>
+     */
+    public void putSettingsAsync(ClusterUpdateSettingsRequest clusterUpdateSettingsRequest,
+            ActionListener<ClusterUpdateSettingsResponse> listener, Header... headers) {
+        restHighLevelClient.performRequestAsyncAndParseEntity(clusterUpdateSettingsRequest, Request::clusterPutSettings,
+                ClusterUpdateSettingsResponse::fromXContent, listener, emptySet(), headers);
+    }
+}

client/rest-high-level/src/main/java/org/elasticsearch/client/Request.java

@@ -29,6 +29,7 @@ import org.apache.http.entity.ByteArrayEntity;
 import org.apache.http.entity.ContentType;
 import org.apache.lucene.util.BytesRef;
 import org.elasticsearch.action.DocWriteRequest;
+import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsRequest;
 import org.elasticsearch.action.admin.indices.alias.IndicesAliasesRequest;
 import org.elasticsearch.action.admin.indices.alias.get.GetAliasesRequest;
 import org.elasticsearch.action.admin.indices.close.CloseIndexRequest;
@@ -528,6 +529,17 @@ public final class Request {
         return new Request(HttpPut.METHOD_NAME, endpoint, params.getParams(), entity);
     }
 
+    static Request clusterPutSettings(ClusterUpdateSettingsRequest clusterUpdateSettingsRequest) throws IOException {
+        Params parameters = Params.builder();
+        parameters.withFlatSettings(clusterUpdateSettingsRequest.flatSettings());
+        parameters.withTimeout(clusterUpdateSettingsRequest.timeout());
+        parameters.withMasterTimeout(clusterUpdateSettingsRequest.masterNodeTimeout());
+
+        String endpoint = buildEndpoint("_cluster/settings");
+        HttpEntity entity = createEntity(clusterUpdateSettingsRequest, REQUEST_BODY_CONTENT_TYPE);
+        return new Request(HttpPut.METHOD_NAME, endpoint, parameters.getParams(), entity);
+    }
+
     private static HttpEntity createEntity(ToXContent toXContent, XContentType xContentType) throws IOException {
         BytesRef source = XContentHelper.toXContent(toXContent, xContentType, false).toBytesRef();
         return new ByteArrayEntity(source.bytes, source.offset, source.length, createContentType(xContentType));

client/rest-high-level/src/main/java/org/elasticsearch/client/RestHighLevelClient.java

@@ -186,6 +186,7 @@ public class RestHighLevelClient implements Closeable {
     private final CheckedConsumer<RestClient, IOException> doClose;
 
     private final IndicesClient indicesClient = new IndicesClient(this);
+    private final ClusterClient clusterClient = new ClusterClient(this);
 
     /**
      * Creates a {@link RestHighLevelClient} given the low level {@link RestClientBuilder} that allows to build the
@@ -240,6 +241,15 @@ public class RestHighLevelClient implements Closeable {
         return indicesClient;
     }
 
+    /**
+     * Provides a {@link ClusterClient} which can be used to access the Cluster API.
+     *
+     * See <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/cluster.html">Cluster API on elastic.co</a>
+     */
+    public final ClusterClient cluster() {
+        return clusterClient;
+    }
+
     /**
      * Executes a bulk request using the Bulk API
      *

client/rest-high-level/src/test/java/org/elasticsearch/client/ClusterClientIT.java

@@ -0,0 +1,108 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.client;
+
+import org.elasticsearch.ElasticsearchException;
+import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsRequest;
+import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsResponse;
+import org.elasticsearch.cluster.routing.allocation.decider.EnableAllocationDecider;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.unit.ByteSizeUnit;
+import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.common.xcontent.support.XContentMapValues;
+import org.elasticsearch.indices.recovery.RecoverySettings;
+import org.elasticsearch.rest.RestStatus;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAcked;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.notNullValue;
+import static org.hamcrest.Matchers.nullValue;
+
+public class ClusterClientIT extends ESRestHighLevelClientTestCase {
+
+    public void testClusterPutSettings() throws IOException {
+        final String transientSettingKey = RecoverySettings.INDICES_RECOVERY_MAX_BYTES_PER_SEC_SETTING.getKey();
+        final int transientSettingValue = 10;
+
+        final String persistentSettingKey = EnableAllocationDecider.CLUSTER_ROUTING_ALLOCATION_ENABLE_SETTING.getKey();
+        final String persistentSettingValue = EnableAllocationDecider.Allocation.NONE.name();
+
+        Settings transientSettings = Settings.builder().put(transientSettingKey, transientSettingValue, ByteSizeUnit.BYTES).build();
+        Map<String, Object> map = new HashMap<>();
+        map.put(persistentSettingKey, persistentSettingValue);
+
+        ClusterUpdateSettingsRequest setRequest = new ClusterUpdateSettingsRequest();
+        setRequest.transientSettings(transientSettings);
+        setRequest.persistentSettings(map);
+
+        ClusterUpdateSettingsResponse setResponse = execute(setRequest, highLevelClient().cluster()::putSettings,
+                highLevelClient().cluster()::putSettingsAsync);
+
+        assertAcked(setResponse);
+        assertThat(setResponse.getTransientSettings().get(transientSettingKey), notNullValue());
+        assertThat(setResponse.getTransientSettings().get(persistentSettingKey), nullValue());
+        assertThat(setResponse.getTransientSettings().get(transientSettingKey),
+                equalTo(transientSettingValue + ByteSizeUnit.BYTES.getSuffix()));
+        assertThat(setResponse.getPersistentSettings().get(transientSettingKey), nullValue());
+        assertThat(setResponse.getPersistentSettings().get(persistentSettingKey), notNullValue());
+        assertThat(setResponse.getPersistentSettings().get(persistentSettingKey), equalTo(persistentSettingValue));
+
+        Map<String, Object> setMap = getAsMap("/_cluster/settings");
+        String transientSetValue = (String) XContentMapValues.extractValue("transient." + transientSettingKey, setMap);
+        assertThat(transientSetValue, equalTo(transientSettingValue + ByteSizeUnit.BYTES.getSuffix()));
+        String persistentSetValue = (String) XContentMapValues.extractValue("persistent." + persistentSettingKey, setMap);
+        assertThat(persistentSetValue, equalTo(persistentSettingValue));
+
+        ClusterUpdateSettingsRequest resetRequest = new ClusterUpdateSettingsRequest();
+        resetRequest.transientSettings(Settings.builder().putNull(transientSettingKey));
+        resetRequest.persistentSettings("{\"" + persistentSettingKey + "\": null }", XContentType.JSON);
+
+        ClusterUpdateSettingsResponse resetResponse = execute(resetRequest, highLevelClient().cluster()::putSettings,
+                highLevelClient().cluster()::putSettingsAsync);
+
+        assertThat(resetResponse.getTransientSettings().get(transientSettingKey), equalTo(null));
+        assertThat(resetResponse.getPersistentSettings().get(persistentSettingKey), equalTo(null));
+        assertThat(resetResponse.getTransientSettings(), equalTo(Settings.EMPTY));
+        assertThat(resetResponse.getPersistentSettings(), equalTo(Settings.EMPTY));
+
+        Map<String, Object> resetMap = getAsMap("/_cluster/settings");
+        String transientResetValue = (String) XContentMapValues.extractValue("transient." + transientSettingKey, resetMap);
+        assertThat(transientResetValue, equalTo(null));
+        String persistentResetValue = (String) XContentMapValues.extractValue("persistent." + persistentSettingKey, resetMap);
+        assertThat(persistentResetValue, equalTo(null));
+    }
+
+    public void testClusterUpdateSettingNonExistent() {
+        String setting = "no_idea_what_you_are_talking_about";
+        int value = 10;
+        ClusterUpdateSettingsRequest clusterUpdateSettingsRequest = new ClusterUpdateSettingsRequest();
+        clusterUpdateSettingsRequest.transientSettings(Settings.builder().put(setting, value).build());
+
+        ElasticsearchException exception = expectThrows(ElasticsearchException.class, () -> execute(clusterUpdateSettingsRequest,
+                highLevelClient().cluster()::putSettings, highLevelClient().cluster()::putSettingsAsync));
+        assertThat(exception.status(), equalTo(RestStatus.BAD_REQUEST));
+        assertThat(exception.getMessage(), equalTo(
+                "Elasticsearch exception [type=illegal_argument_exception, reason=transient setting [" + setting + "], not recognized]"));
+    }
+}

client/rest-high-level/src/test/java/org/elasticsearch/client/IndicesClientIT.java

@@ -167,7 +167,6 @@ public class IndicesClientIT extends ESRestHighLevelClientTestCase {
         }
     }
 
-    @SuppressWarnings({"unchecked", "rawtypes"})
     public void testPutMapping() throws IOException {
         {
             // Add mappings to index

client/rest-high-level/src/test/java/org/elasticsearch/client/RequestTests.java

@@ -30,6 +30,7 @@ import org.apache.http.entity.ContentType;
 import org.apache.http.entity.StringEntity;
 import org.apache.http.util.EntityUtils;
 import org.elasticsearch.action.DocWriteRequest;
+import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsRequest;
 import org.elasticsearch.action.admin.indices.alias.IndicesAliasesRequest;
 import org.elasticsearch.action.admin.indices.alias.IndicesAliasesRequest.AliasActions;
 import org.elasticsearch.action.admin.indices.alias.get.GetAliasesRequest;
@@ -272,7 +273,7 @@ public class RequestTests extends ESTestCase {
         Map<String, String> expectedParams = new HashMap<>();
         setRandomIndicesOptions(getIndexRequest::indicesOptions, getIndexRequest::indicesOptions, expectedParams);
         setRandomLocal(getIndexRequest, expectedParams);
-        setRandomFlatSettings(getIndexRequest, expectedParams);
+        setRandomFlatSettings(getIndexRequest::flatSettings, expectedParams);
         setRandomHumanReadable(getIndexRequest, expectedParams);
         setRandomIncludeDefaults(getIndexRequest, expectedParams);
 
@@ -1115,14 +1116,10 @@ public class RequestTests extends ESTestCase {
             if (randomBoolean()) {
                 randomAliases(createIndexRequest);
             }
-            if (randomBoolean()) {
+            setRandomWaitForActiveShards(createIndexRequest::waitForActiveShards, expectedParams);
-                setRandomWaitForActiveShards(createIndexRequest::waitForActiveShards, expectedParams);
-            }
             resizeRequest.setTargetIndex(createIndexRequest);
         } else {
-            if (randomBoolean()) {
+            setRandomWaitForActiveShards(resizeRequest::setWaitForActiveShards, expectedParams);
-                setRandomWaitForActiveShards(resizeRequest::setWaitForActiveShards, expectedParams);
-            }
         }
 
         Request request = function.apply(resizeRequest);
@@ -1133,6 +1130,19 @@ public class RequestTests extends ESTestCase {
         assertEquals(expectedParams, request.getParameters());
         assertToXContentBody(resizeRequest, request.getEntity());
     }
+    
+    public void testClusterPutSettings() throws IOException {
+        ClusterUpdateSettingsRequest request = new ClusterUpdateSettingsRequest();
+        Map<String, String> expectedParams = new HashMap<>();
+        setRandomFlatSettings(request::flatSettings, expectedParams);
+        setRandomMasterTimeout(request, expectedParams);
+        setRandomTimeout(request::timeout, AcknowledgedRequest.DEFAULT_ACK_TIMEOUT, expectedParams);
+
+        Request expectedRequest = Request.clusterPutSettings(request);
+        assertEquals("/_cluster/settings", expectedRequest.getEndpoint());
+        assertEquals(HttpPut.METHOD_NAME, expectedRequest.getMethod());
+        assertEquals(expectedParams, expectedRequest.getParameters());
+    }
 
     private static void assertToXContentBody(ToXContent expectedBody, HttpEntity actualEntity) throws IOException {
         BytesReference expectedBytes = XContentHelper.toXContent(expectedBody, REQUEST_BODY_CONTENT_TYPE, false);
@@ -1289,16 +1299,6 @@ public class RequestTests extends ESTestCase {
         }
     }
 
-    private static void setRandomFlatSettings(GetIndexRequest request, Map<String, String> expectedParams) {
-        if (randomBoolean()) {
-            boolean flatSettings = randomBoolean();
-            request.flatSettings(flatSettings);
-            if (flatSettings) {
-                expectedParams.put("flat_settings", String.valueOf(flatSettings));
-            }
-        }
-    }
-
     private static void setRandomLocal(MasterNodeReadRequest<?> request, Map<String, String> expectedParams) {
         if (randomBoolean()) {
             boolean local = randomBoolean();
@@ -1319,6 +1319,16 @@ public class RequestTests extends ESTestCase {
         }
     }
 
+    private static void setRandomFlatSettings(Consumer<Boolean> setter, Map<String, String> expectedParams) {
+        if (randomBoolean()) {
+            boolean flatSettings = randomBoolean();
+            setter.accept(flatSettings);
+            if (flatSettings) {
+                expectedParams.put("flat_settings", String.valueOf(flatSettings));
+            }
+        }
+    }
+
     private static void setRandomMasterTimeout(MasterNodeRequest<?> request, Map<String, String> expectedParams) {
         if (randomBoolean()) {
             String masterTimeout = randomTimeValue();

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/ClusterClientDocumentationIT.java

@@ -0,0 +1,180 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.client.documentation;
+
+import org.elasticsearch.action.ActionListener;
+import org.elasticsearch.action.LatchedActionListener;
+import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsRequest;
+import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsResponse;
+import org.elasticsearch.client.ESRestHighLevelClientTestCase;
+import org.elasticsearch.client.RestHighLevelClient;
+import org.elasticsearch.cluster.routing.allocation.decider.EnableAllocationDecider;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.unit.ByteSizeUnit;
+import org.elasticsearch.common.unit.TimeValue;
+import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.indices.recovery.RecoverySettings;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import static org.hamcrest.Matchers.equalTo;
+
+/**
+ * This class is used to generate the Java Cluster API documentation.
+ * You need to wrap your code between two tags like:
+ * // tag::example[]
+ * // end::example[]
+ *
+ * Where example is your tag name.
+ *
+ * Then in the documentation, you can extract what is between tag and end tags with
+ * ["source","java",subs="attributes,callouts,macros"]
+ * --------------------------------------------------
+ * include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[example]
+ * --------------------------------------------------
+ */
+public class ClusterClientDocumentationIT extends ESRestHighLevelClientTestCase {
+
+    public void testClusterPutSettings() throws IOException {
+        RestHighLevelClient client = highLevelClient();
+
+        // tag::put-settings-request
+        ClusterUpdateSettingsRequest request = new ClusterUpdateSettingsRequest();
+        // end::put-settings-request
+
+        // tag::put-settings-create-settings
+        String transientSettingKey = 
+                RecoverySettings.INDICES_RECOVERY_MAX_BYTES_PER_SEC_SETTING.getKey();
+        int transientSettingValue = 10;
+        Settings transientSettings = 
+                Settings.builder()
+                .put(transientSettingKey, transientSettingValue, ByteSizeUnit.BYTES)
+                .build(); // <1>
+
+        String persistentSettingKey = 
+                EnableAllocationDecider.CLUSTER_ROUTING_ALLOCATION_ENABLE_SETTING.getKey();
+        String persistentSettingValue = 
+                EnableAllocationDecider.Allocation.NONE.name();
+        Settings persistentSettings = 
+                Settings.builder()
+                .put(persistentSettingKey, persistentSettingValue)
+                .build(); // <2>
+        // end::put-settings-create-settings
+
+        // tag::put-settings-request-cluster-settings
+        request.transientSettings(transientSettings); // <1>
+        request.persistentSettings(persistentSettings); // <2>
+        // end::put-settings-request-cluster-settings
+
+        {
+            // tag::put-settings-settings-builder
+            Settings.Builder transientSettingsBuilder = 
+                    Settings.builder()
+                    .put(transientSettingKey, transientSettingValue, ByteSizeUnit.BYTES); 
+            request.transientSettings(transientSettingsBuilder); // <1>
+            // end::put-settings-settings-builder
+        }
+        {
+            // tag::put-settings-settings-map
+            Map<String, Object> map = new HashMap<>();
+            map.put(transientSettingKey
+                    , transientSettingValue + ByteSizeUnit.BYTES.getSuffix());
+            request.transientSettings(map); // <1>
+            // end::put-settings-settings-map
+        }
+        {
+            // tag::put-settings-settings-source
+            request.transientSettings(
+                    "{\"indices.recovery.max_bytes_per_sec\": \"10b\"}"
+                    , XContentType.JSON); // <1>
+            // end::put-settings-settings-source
+        }
+
+        // tag::put-settings-request-timeout
+        request.timeout(TimeValue.timeValueMinutes(2)); // <1>
+        request.timeout("2m"); // <2>
+        // end::put-settings-request-timeout
+        // tag::put-settings-request-masterTimeout
+        request.masterNodeTimeout(TimeValue.timeValueMinutes(1)); // <1>
+        request.masterNodeTimeout("1m"); // <2>
+        // end::put-settings-request-masterTimeout
+
+        // tag::put-settings-request-flat-settings
+        request.flatSettings(true); // <1>
+        // end::put-settings-request-flat-settings
+
+        // tag::put-settings-execute
+        ClusterUpdateSettingsResponse response = client.cluster().putSettings(request);
+        // end::put-settings-execute
+
+        // tag::put-settings-response
+        boolean acknowledged = response.isAcknowledged(); // <1>
+        Settings transientSettingsResponse = response.getTransientSettings(); // <2>
+        Settings persistentSettingsResponse = response.getPersistentSettings(); // <3>
+        // end::put-settings-response
+        assertTrue(acknowledged);
+        assertThat(transientSettingsResponse.get(transientSettingKey), equalTo(transientSettingValue + ByteSizeUnit.BYTES.getSuffix()));
+        assertThat(persistentSettingsResponse.get(persistentSettingKey), equalTo(persistentSettingValue));
+
+        // tag::put-settings-request-reset-transient
+        request.transientSettings(Settings.builder().putNull(transientSettingKey).build()); // <1>
+        // tag::put-settings-request-reset-transient
+        request.persistentSettings(Settings.builder().putNull(persistentSettingKey));
+        ClusterUpdateSettingsResponse resetResponse = client.cluster().putSettings(request);
+
+        assertTrue(resetResponse.isAcknowledged());
+    }
+
+    public void testClusterUpdateSettingsAsync() throws Exception {
+        RestHighLevelClient client = highLevelClient();
+        {
+            ClusterUpdateSettingsRequest request = new ClusterUpdateSettingsRequest();
+
+            // tag::put-settings-execute-listener
+            ActionListener<ClusterUpdateSettingsResponse> listener = 
+                    new ActionListener<ClusterUpdateSettingsResponse>() {
+                @Override
+                public void onResponse(ClusterUpdateSettingsResponse response) {
+                    // <1>
+                }
+
+                @Override
+                public void onFailure(Exception e) {
+                    // <2>
+                }
+            };
+            // end::put-settings-execute-listener
+
+            // Replace the empty listener by a blocking listener in test
+            final CountDownLatch latch = new CountDownLatch(1);
+            listener = new LatchedActionListener<>(listener, latch);
+
+            // tag::put-settings-execute-async
+            client.cluster().putSettingsAsync(request, listener); // <1>
+            // end::put-settings-execute-async
+
+            assertTrue(latch.await(30L, TimeUnit.SECONDS));
+        }
+    }
+}

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/IndicesClientDocumentationIT.java

@@ -70,7 +70,7 @@ import java.util.concurrent.TimeUnit;
  * Then in the documentation, you can extract what is between tag and end tags with
  * ["source","java",subs="attributes,callouts,macros"]
  * --------------------------------------------------
- * include-tagged::{doc-tests}/CRUDDocumentationIT.java[example]
+ * include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[example]
  * --------------------------------------------------
  */
 public class IndicesClientDocumentationIT extends ESRestHighLevelClientTestCase {
@@ -105,7 +105,7 @@ public class IndicesClientDocumentationIT extends ESRestHighLevelClientTestCase
         }
     }
 
-    public void testIndicesExistAsync() throws IOException {
+    public void testIndicesExistAsync() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
         {
@@ -138,6 +138,8 @@ public class IndicesClientDocumentationIT extends ESRestHighLevelClientTestCase
             // tag::indices-exists-async
             client.indices().existsAsync(request, listener); // <1>
             // end::indices-exists-async
+
+            assertTrue(latch.await(30L, TimeUnit.SECONDS));
         }
     }
     public void testDeleteIndex() throws IOException {

docs/java-rest/high-level/cluster/put_settings.asciidoc

@@ -0,0 +1,129 @@
+[[java-rest-high-cluster-put-settings]]
+=== Cluster Update Settings API
+
+The Cluster Update Settings API allows to update cluster wide settings.
+
+[[java-rest-high-cluster-put-settings-request]]
+==== Cluster Update Settings Request
+
+A `ClusterUpdateSettingsRequest`:
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-request]
+--------------------------------------------------
+
+==== Cluster Settings
+At least one setting to be updated must be provided:
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-request-cluster-settings]
+--------------------------------------------------
+<1> Sets the transient settings to be applied
+<2> Sets the persistent setting to be applied
+
+==== Providing the Settings
+The settings to be applied can be provided in different ways:
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-create-settings]
+--------------------------------------------------
+<1> Creates a transient setting as `Settings`
+<2> Creates a persistent setting as `Settings`
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-settings-builder]
+--------------------------------------------------
+<1> Settings provided as `Settings.Builder`
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-settings-source]
+--------------------------------------------------
+<1> Settings provided as `String`
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-settings-map]
+--------------------------------------------------
+<1> Settings provided as a `Map`
+
+==== Optional Arguments
+The following arguments can optionally be provided:
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-request-flat-settings]
+--------------------------------------------------
+<1> Wether the updated settings returned in the `ClusterUpdateSettings` should
+be in a flat format
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-request-timeout]
+--------------------------------------------------
+<1> Timeout to wait for the all the nodes to acknowledge the settings were applied
+as a `TimeValue`
+<2> Timeout to wait for the all the nodes to acknowledge the settings were applied
+as a `String`
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-request-masterTimeout]
+--------------------------------------------------
+<1> Timeout to connect to the master node as a `TimeValue`
+<2> Timeout to connect to the master node as a `String`
+
+[[java-rest-high-cluster-put-settings-sync]]
+==== Synchronous Execution
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-execute]
+--------------------------------------------------
+
+[[java-rest-high-cluster-put-settings-async]]
+==== Asynchronous Execution
+
+The asynchronous execution of a cluster update settings requires both the
+`ClusterUpdateSettingsRequest` instance and an `ActionListener` instance to be
+passed to the asynchronous method:
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-execute-async]
+--------------------------------------------------
+<1> The `ClusterUpdateSettingsRequest` to execute and the `ActionListener`
+to use when the execution completes
+
+The asynchronous method does not block and returns immediately. Once it is
+completed the `ActionListener` is called back using the `onResponse` method
+if the execution successfully completed or using the `onFailure` method if
+it failed.
+
+A typical listener for `ClusterUpdateSettingsResponse` looks like:
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-execute-listener]
+--------------------------------------------------
+<1> Called when the execution is successfully completed. The response is
+provided as an argument
+<2> Called in case of a failure. The raised exception is provided as an argument
+
+[[java-rest-high-cluster-put-settings-response]]
+==== Cluster Update Settings Response
+
+The returned `ClusterUpdateSettings` allows to retrieve information about the
+executed operation as follows:
+
+["source","java",subs="attributes,callouts,macros"]
+--------------------------------------------------
+include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[put-settings-response]
+--------------------------------------------------
+<1> Indicates whether all of the nodes have acknowledged the request
+<2> Indicates which transient settings have been applied
+<3> Indicates which persistent settings have been applied

docs/java-rest/high-level/indices/put_mapping.asciidoc

@@ -20,7 +20,7 @@ A description of the fields to create on the mapping; if not defined, the mappin
 --------------------------------------------------
 include-tagged::{doc-tests}/IndicesClientDocumentationIT.java[put-mapping-request-source]
 --------------------------------------------------
-<1> The mapping source provided as a `String`
+<1> Mapping source provided as a `String`
 
 ==== Providing the mapping source
 The mapping source can be provided in different ways in addition to

docs/java-rest/high-level/supported-apis.asciidoc

@@ -71,3 +71,10 @@ include::indices/put_mapping.asciidoc[]
 include::indices/update_aliases.asciidoc[]
 include::indices/exists_alias.asciidoc[]
 
+== Cluster APIs
+
+The Java High Level REST Client supports the following Cluster APIs:
+
+* <<java-rest-high-cluster-put-settings>>
+
+include::cluster/put_settings.asciidoc[]

server/src/main/java/org/elasticsearch/action/admin/cluster/settings/ClusterUpdateSettingsRequest.java

@@ -22,26 +22,42 @@ package org.elasticsearch.action.admin.cluster.settings;
 import org.elasticsearch.ElasticsearchGenerationException;
 import org.elasticsearch.action.ActionRequestValidationException;
 import org.elasticsearch.action.support.master.AcknowledgedRequest;
+import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.xcontent.ObjectParser;
+import org.elasticsearch.common.xcontent.ToXContentObject;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentFactory;
+import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.common.xcontent.XContentType;
 
 import java.io.IOException;
 import java.util.Map;
 
 import static org.elasticsearch.action.ValidateActions.addValidationError;
-import static org.elasticsearch.common.settings.Settings.Builder.EMPTY_SETTINGS;
 import static org.elasticsearch.common.settings.Settings.readSettingsFromStream;
 import static org.elasticsearch.common.settings.Settings.writeSettingsToStream;
+import static org.elasticsearch.common.settings.Settings.Builder.EMPTY_SETTINGS;
 
 /**
  * Request for an update cluster settings action
  */
-public class ClusterUpdateSettingsRequest extends AcknowledgedRequest<ClusterUpdateSettingsRequest> {
+public class ClusterUpdateSettingsRequest extends AcknowledgedRequest<ClusterUpdateSettingsRequest> implements ToXContentObject {
 
+    private static final ParseField PERSISTENT = new ParseField("persistent");
+    private static final ParseField TRANSIENT = new ParseField("transient");
+
+    private static final ObjectParser<ClusterUpdateSettingsRequest, Void> PARSER = new ObjectParser<>("cluster_update_settings_request",
+            false, ClusterUpdateSettingsRequest::new);
+
+    static {
+        PARSER.declareObject((r, p) -> r.persistentSettings = p, (p, c) -> Settings.fromXContent(p), PERSISTENT);
+        PARSER.declareObject((r, t) -> r.transientSettings = t, (p, c) -> Settings.fromXContent(p), TRANSIENT);
+    }
+
+    private boolean flatSettings = false;
     private Settings transientSettings = EMPTY_SETTINGS;
     private Settings persistentSettings = EMPTY_SETTINGS;
 
@@ -57,6 +73,29 @@ public class ClusterUpdateSettingsRequest extends AcknowledgedRequest<ClusterUpd
         return validationException;
     }
 
+    /**
+     * Sets the value of "flat_settings".
+     * Used only by the high-level REST client.
+     * 
+     * @param flatSettings
+     *            value of "flat_settings" flag to be set
+     * @return this request
+     */
+    public ClusterUpdateSettingsRequest flatSettings(boolean flatSettings) {
+        this.flatSettings = flatSettings;
+        return this;
+    }
+
+    /**
+     * Return settings in flat format.
+     * Used only by the high-level REST client.
+     * 
+     * @return <code>true</code> if settings need to be returned in flat format; <code>false</code> otherwise.
+     */
+    public boolean flatSettings() {
+        return flatSettings;
+    }
+
     public Settings transientSettings() {
         return transientSettings;
     }
@@ -92,7 +131,7 @@ public class ClusterUpdateSettingsRequest extends AcknowledgedRequest<ClusterUpd
     /**
      * Sets the transient settings to be updated. They will not survive a full cluster restart
      */
-    @SuppressWarnings("unchecked")
+    @SuppressWarnings({"unchecked", "rawtypes"})
     public ClusterUpdateSettingsRequest transientSettings(Map source) {
         try {
             XContentBuilder builder = XContentFactory.contentBuilder(XContentType.JSON);
@@ -131,7 +170,7 @@ public class ClusterUpdateSettingsRequest extends AcknowledgedRequest<ClusterUpd
     /**
      * Sets the persistent settings to be updated. They will get applied cross restarts
      */
-    @SuppressWarnings("unchecked")
+    @SuppressWarnings({"unchecked", "rawtypes"})
     public ClusterUpdateSettingsRequest persistentSettings(Map source) {
         try {
             XContentBuilder builder = XContentFactory.contentBuilder(XContentType.JSON);
@@ -156,4 +195,21 @@ public class ClusterUpdateSettingsRequest extends AcknowledgedRequest<ClusterUpd
         writeSettingsToStream(transientSettings, out);
         writeSettingsToStream(persistentSettings, out);
     }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.startObject();
+        builder.startObject(PERSISTENT.getPreferredName());
+        persistentSettings.toXContent(builder, params);
+        builder.endObject();
+        builder.startObject(TRANSIENT.getPreferredName());
+        transientSettings.toXContent(builder, params);
+        builder.endObject();
+        builder.endObject();
+        return builder;
+    }
+
+    public static ClusterUpdateSettingsRequest fromXContent(XContentParser parser) throws IOException {
+        return PARSER.apply(parser, null);
+    }
 }

server/src/main/java/org/elasticsearch/action/admin/cluster/settings/ClusterUpdateSettingsResponse.java

@@ -20,16 +20,32 @@
 package org.elasticsearch.action.admin.cluster.settings;
 
 import org.elasticsearch.action.support.master.AcknowledgedResponse;
+import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.xcontent.ConstructingObjectParser;
+import org.elasticsearch.common.xcontent.ToXContentObject;
+import org.elasticsearch.common.xcontent.XContentBuilder;
+import org.elasticsearch.common.xcontent.XContentParser;
 
 import java.io.IOException;
 
 /**
  * A response for a cluster update settings action.
  */
-public class ClusterUpdateSettingsResponse extends AcknowledgedResponse {
+public class ClusterUpdateSettingsResponse extends AcknowledgedResponse implements ToXContentObject {
+
+    private static final ParseField PERSISTENT = new ParseField("persistent");
+    private static final ParseField TRANSIENT = new ParseField("transient");
+
+    private static final ConstructingObjectParser<ClusterUpdateSettingsResponse, Void> PARSER = new ConstructingObjectParser<>(
+            "cluster_update_settings_response", true, a -> new ClusterUpdateSettingsResponse((boolean) a[0]));
+    static {
+        declareAcknowledgedField(PARSER);
+        PARSER.declareObject((r, p) -> r.persistentSettings = p, (p, c) -> Settings.fromXContent(p), PERSISTENT);
+        PARSER.declareObject((r, t) -> r.transientSettings = t, (p, c) -> Settings.fromXContent(p), TRANSIENT);
+    }
 
     Settings transientSettings;
     Settings persistentSettings;
@@ -39,6 +55,10 @@ public class ClusterUpdateSettingsResponse extends AcknowledgedResponse {
         this.transientSettings = Settings.EMPTY;
     }
 
+    ClusterUpdateSettingsResponse(boolean acknowledged) {
+        super(acknowledged);
+    }
+
     ClusterUpdateSettingsResponse(boolean acknowledged, Settings transientSettings, Settings persistentSettings) {
         super(acknowledged);
         this.persistentSettings = persistentSettings;
@@ -68,4 +88,22 @@ public class ClusterUpdateSettingsResponse extends AcknowledgedResponse {
         Settings.writeSettingsToStream(persistentSettings, out);
         writeAcknowledged(out);
     }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.startObject();
+        addAcknowledgedField(builder);
+        builder.startObject(PERSISTENT.getPreferredName());
+        persistentSettings.toXContent(builder, params);
+        builder.endObject();
+        builder.startObject(TRANSIENT.getPreferredName());
+        transientSettings.toXContent(builder, params);
+        builder.endObject();
+        builder.endObject();
+        return builder;
+    }
+
+    public static ClusterUpdateSettingsResponse fromXContent(XContentParser parser) throws IOException {
+        return PARSER.apply(parser, null);
+    }
 }

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

@@ -26,8 +26,6 @@ import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.util.ArrayUtils;
 
 import java.io.IOException;
-import java.util.Arrays;
-import java.util.List;
 
 /**
  * A request to delete an index. Best created with {@link org.elasticsearch.client.Requests#deleteIndexRequest(String)}.
@@ -122,6 +120,8 @@ public class GetIndexRequest extends ClusterInfoRequest<GetIndexRequest> {
 
     /**
      * Sets the value of "flat_settings".
+     * Used only by the high-level REST client.
+     * 
      * @param flatSettings value of "flat_settings" flag to be set
      * @return this request
      */
@@ -132,6 +132,8 @@ public class GetIndexRequest extends ClusterInfoRequest<GetIndexRequest> {
 
     /**
      * Return settings in flat format.
+     * Used only by the high-level REST client.
+     * 
      * @return <code>true</code> if settings need to be returned in flat format; <code>false</code> otherwise.
      */
     public boolean flatSettings() {
@@ -140,6 +142,8 @@ public class GetIndexRequest extends ClusterInfoRequest<GetIndexRequest> {
 
     /**
      * Sets the value of "include_defaults".
+     * Used only by the high-level REST client.
+     * 
      * @param includeDefaults value of "include_defaults" to be set.
      * @return this request
      */
@@ -150,6 +154,8 @@ public class GetIndexRequest extends ClusterInfoRequest<GetIndexRequest> {
 
     /**
      * Whether to return all default settings for each of the indices.
+     * Used only by the high-level REST client.
+     * 
      * @return <code>true</code> if defaults settings for each of the indices need to returned;
      * <code>false</code> otherwise.
      */

server/src/main/java/org/elasticsearch/rest/action/admin/cluster/RestClusterUpdateSettingsAction.java

@@ -20,22 +20,25 @@
 package org.elasticsearch.rest.action.admin.cluster;
 
 import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsRequest;
-import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsResponse;
 import org.elasticsearch.client.Requests;
 import org.elasticsearch.client.node.NodeClient;
+import org.elasticsearch.common.ParseField;
 import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.rest.BaseRestHandler;
 import org.elasticsearch.rest.RestController;
 import org.elasticsearch.rest.RestRequest;
-import org.elasticsearch.rest.action.AcknowledgedRestListener;
+import org.elasticsearch.rest.action.RestToXContentListener;
 
 import java.io.IOException;
 import java.util.Map;
 import java.util.Set;
 
 public class RestClusterUpdateSettingsAction extends BaseRestHandler {
+
+    private static final String PERSISTENT = "persistent";
+    private static final String TRANSIENT = "transient";
+
     public RestClusterUpdateSettingsAction(Settings settings, RestController controller) {
         super(settings);
         controller.registerHandler(RestRequest.Method.PUT, "/_cluster/settings", this);
@@ -56,26 +59,14 @@ public class RestClusterUpdateSettingsAction extends BaseRestHandler {
         try (XContentParser parser = request.contentParser()) {
             source = parser.map();
         }
-        if (source.containsKey("transient")) {
+        if (source.containsKey(TRANSIENT)) {
-            clusterUpdateSettingsRequest.transientSettings((Map) source.get("transient"));
+            clusterUpdateSettingsRequest.transientSettings((Map) source.get(TRANSIENT));
         }
-        if (source.containsKey("persistent")) {
+        if (source.containsKey(PERSISTENT)) {
-            clusterUpdateSettingsRequest.persistentSettings((Map) source.get("persistent"));
+            clusterUpdateSettingsRequest.persistentSettings((Map) source.get(PERSISTENT));
         }
 
-        return channel -> client.admin().cluster().updateSettings(clusterUpdateSettingsRequest,
+        return channel -> client.admin().cluster().updateSettings(clusterUpdateSettingsRequest, new RestToXContentListener<>(channel));
-                new AcknowledgedRestListener<ClusterUpdateSettingsResponse>(channel) {
-                    @Override
-                    protected void addCustomFields(XContentBuilder builder, ClusterUpdateSettingsResponse response) throws IOException {
-                        builder.startObject("persistent");
-                        response.getPersistentSettings().toXContent(builder, request);
-                        builder.endObject();
-
-                        builder.startObject("transient");
-                        response.getTransientSettings().toXContent(builder, request);
-                        builder.endObject();
-                    }
-                });
     }
 
     @Override

server/src/test/java/org/elasticsearch/action/admin/cluster/settings/ClusterUpdateSettingsRequestTests.java

@@ -0,0 +1,74 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.action.admin.cluster.settings;
+
+import org.elasticsearch.common.bytes.BytesReference;
+import org.elasticsearch.common.xcontent.ToXContent;
+import org.elasticsearch.common.xcontent.XContentParser;
+import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.test.ESTestCase;
+import org.elasticsearch.test.XContentTestUtils;
+
+import java.io.IOException;
+import java.util.Collections;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+
+public class ClusterUpdateSettingsRequestTests extends ESTestCase {
+
+    public void testFromXContent() throws IOException {
+        doFromXContentTestWithRandomFields(false);
+    }
+
+    public void testFromXContentWithRandomFields() throws IOException {
+        doFromXContentTestWithRandomFields(true);
+    }
+
+    private void doFromXContentTestWithRandomFields(boolean addRandomFields) throws IOException {
+        final ClusterUpdateSettingsRequest request = createTestItem();
+        boolean humanReadable = randomBoolean();
+        final XContentType xContentType = XContentType.JSON;
+        BytesReference originalBytes = toShuffledXContent(request, xContentType, ToXContent.EMPTY_PARAMS, humanReadable);
+
+        if (addRandomFields) {
+            String unsupportedField = "unsupported_field";
+            BytesReference mutated = XContentTestUtils.insertIntoXContent(xContentType.xContent(), originalBytes,
+                    Collections.singletonList(""), () -> unsupportedField, () -> randomAlphaOfLengthBetween(3, 10)).bytes();
+            IllegalArgumentException iae = expectThrows(IllegalArgumentException.class,
+                    () -> ClusterUpdateSettingsRequest.fromXContent(createParser(xContentType.xContent(), mutated)));
+            assertThat(iae.getMessage(),
+                    equalTo("[cluster_update_settings_request] unknown field [" + unsupportedField + "], parser not found"));
+        } else {
+            XContentParser parser = createParser(xContentType.xContent(), originalBytes);
+            ClusterUpdateSettingsRequest parsedRequest = ClusterUpdateSettingsRequest.fromXContent(parser);
+
+            assertNull(parser.nextToken());
+            assertThat(parsedRequest.transientSettings(), equalTo(request.transientSettings()));
+            assertThat(parsedRequest.persistentSettings(), equalTo(request.persistentSettings()));
+        }
+    }
+
+    private static ClusterUpdateSettingsRequest createTestItem() {
+        ClusterUpdateSettingsRequest request = new ClusterUpdateSettingsRequest();
+        request.persistentSettings(ClusterUpdateSettingsResponseTests.randomClusterSettings(0, 2));
+        request.transientSettings(ClusterUpdateSettingsResponseTests.randomClusterSettings(0, 2));
+        return request;
+    }
+}

server/src/test/java/org/elasticsearch/action/admin/cluster/settings/ClusterUpdateSettingsResponseTests.java

@@ -0,0 +1,83 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.action.admin.cluster.settings;
+
+import org.elasticsearch.common.bytes.BytesReference;
+import org.elasticsearch.common.settings.ClusterSettings;
+import org.elasticsearch.common.settings.Setting;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.settings.Settings.Builder;
+import org.elasticsearch.common.xcontent.ToXContent;
+import org.elasticsearch.common.xcontent.XContentParser;
+import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.test.ESTestCase;
+
+import java.io.IOException;
+
+import static org.elasticsearch.test.XContentTestUtils.insertRandomFields;
+import static org.hamcrest.CoreMatchers.equalTo;
+
+public class ClusterUpdateSettingsResponseTests extends ESTestCase {
+
+    public void testFromXContent() throws IOException {
+        doFromXContentTestWithRandomFields(false);
+    }
+
+    public void testFromXContentWithRandomFields() throws IOException {
+        doFromXContentTestWithRandomFields(true);
+    }
+
+    private void doFromXContentTestWithRandomFields(boolean addRandomFields) throws IOException {
+        final ClusterUpdateSettingsResponse response = createTestItem();
+        boolean humanReadable = randomBoolean();
+        final XContentType xContentType = XContentType.JSON;
+
+        BytesReference originalBytes = toShuffledXContent(response, xContentType, ToXContent.EMPTY_PARAMS, humanReadable);
+        BytesReference mutated;
+        if (addRandomFields) {
+            mutated = insertRandomFields(xContentType, originalBytes, p -> p.startsWith("transient") || p.startsWith("persistent"),
+                    random());
+        } else {
+            mutated = originalBytes;
+        }
+
+        XContentParser parser = createParser(xContentType.xContent(), mutated);
+        ClusterUpdateSettingsResponse parsedResponse = ClusterUpdateSettingsResponse.fromXContent(parser);
+
+        assertNull(parser.nextToken());
+        assertThat(parsedResponse.isAcknowledged(), equalTo(response.isAcknowledged()));
+        assertThat(response.transientSettings, equalTo(response.transientSettings));
+        assertThat(response.persistentSettings, equalTo(response.persistentSettings));
+    }
+
+    public static Settings randomClusterSettings(int min, int max) {
+        int num = randomIntBetween(min, max);
+        Builder builder = Settings.builder();
+        for (int i = 0; i < num; i++) {
+            Setting<?> setting = randomFrom(ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
+            builder.put(setting.getKey(), randomAlphaOfLengthBetween(2, 10));
+        }
+        return builder.build();
+    }
+
+    private static ClusterUpdateSettingsResponse createTestItem() {
+        return new ClusterUpdateSettingsResponse(randomBoolean(), randomClusterSettings(0, 2), randomClusterSettings(0, 2));
+    }
+}

test/framework/src/main/java/org/elasticsearch/test/ESTestCase.java

@@ -29,6 +29,7 @@ import com.carrotsearch.randomizedtesting.generators.RandomNumbers;
 import com.carrotsearch.randomizedtesting.generators.RandomPicks;
 import com.carrotsearch.randomizedtesting.generators.RandomStrings;
 import com.carrotsearch.randomizedtesting.rules.TestRuleAdapter;
+
 import org.apache.logging.log4j.Level;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;

test/framework/src/main/java/org/elasticsearch/test/XContentTestUtils.java

@@ -286,7 +286,7 @@ public final class XContentTestUtils {
      * {@link ObjectPath}.
      * The key/value arguments can suppliers that either return fixed or random values.
      */
-    static XContentBuilder insertIntoXContent(XContent xContent, BytesReference original, List<String> paths, Supplier<String> key,
+    public static XContentBuilder insertIntoXContent(XContent xContent, BytesReference original, List<String> paths, Supplier<String> key,
             Supplier<Object> value) throws IOException {
         ObjectPath object = ObjectPath.createFromXContent(xContent, original);
         for (String path : paths) {