HLRest: Move xPackInfo() to xPack().info() (#31905)

Originally I put the X-Pack info object into the top level rest client
object. I did that because we thought we'd like to squash `xpack` from
the name of the X-Pack APIs now that it is part of the default
distribution. We still kind of want to do that, but at least for now we
feel like it is better to keep the high level rest client aligned with
the other language clients like C# and Python. This shifts the X-Pack
info API to align with its json spec file.

Relates to #31870

Author: nik9000

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

@@ -66,8 +66,6 @@
 import org.elasticsearch.index.rankeval.RankEvalRequest;
 import org.elasticsearch.index.rankeval.RankEvalResponse;
 import org.elasticsearch.plugins.spi.NamedXContentProvider;
-import org.elasticsearch.protocol.xpack.XPackInfoRequest;
-import org.elasticsearch.protocol.xpack.XPackInfoResponse;
 import org.elasticsearch.rest.BytesRestResponse;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.script.mustache.MultiSearchTemplateRequest;
@@ -204,6 +202,7 @@ public class RestHighLevelClient implements Closeable {
     private final IngestClient ingestClient = new IngestClient(this);
     private final SnapshotClient snapshotClient = new SnapshotClient(this);
     private final TasksClient tasksClient = new TasksClient(this);
+    private final XPackClient xPackClient = new XPackClient(this);
 
     /**
      * Creates a {@link RestHighLevelClient} given the low level {@link RestClientBuilder} that allows to build the
@@ -294,6 +293,19 @@ public final TasksClient tasks() {
         return tasksClient;
     }
 
+    /**
+     * A wrapper for the {@link RestHighLevelClient} that provides methods for
+     * accessing the Elastic Licensed X-Pack APIs that are shipped with the
+     * default distribution of Elasticsearch. All of these APIs will 404 if run
+     * against the OSS distribution of Elasticsearch.
+     * <p>
+     * See the <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/xpack-api.html">
+     * X-Pack APIs on elastic.co</a> for more information.
+     */
+    public final XPackClient xpack() {
+        return xPackClient;
+    }
+
     /**
      * Executes a bulk request using the Bulk API.
      * See <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-bulk.html">Bulk API on elastic.co</a>
@@ -794,34 +806,6 @@ public final void fieldCapsAsync(FieldCapabilitiesRequest fieldCapabilitiesReque
             FieldCapabilitiesResponse::fromXContent, listener, emptySet());
     }
 
-    /**
-     * Fetch information about X-Pack from the cluster if it is installed.
-     * See <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/info-api.html">
-     * the docs</a> for more.
-     * @param request the request
-     * @param options the request options (e.g. headers), use {@link RequestOptions#DEFAULT} if nothing needs to be customized
-     * @return the response
-     * @throws IOException in case there is a problem sending the request or parsing back the response
-     */
-    public XPackInfoResponse xPackInfo(XPackInfoRequest request, RequestOptions options) throws IOException {
-        return performRequestAndParseEntity(request, RequestConverters::xPackInfo, options,
-            XPackInfoResponse::fromXContent, emptySet());
-    }
-
-    /**
-     * Fetch information about X-Pack from the cluster if it is installed.
-     * See <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/info-api.html">
-     * the docs</a> for more.
-     * @param request the request
-     * @param options the request options (e.g. headers), use {@link RequestOptions#DEFAULT} if nothing needs to be customized
-     * @param listener the listener to be notified upon request completion
-     */
-    public void xPackInfoAsync(XPackInfoRequest request, RequestOptions options,
-                                  ActionListener<XPackInfoResponse> listener) {
-        performRequestAsyncAndParseEntity(request, RequestConverters::xPackInfo, options,
-            XPackInfoResponse::fromXContent, listener, emptySet());
-    }
-
     protected final <Req extends ActionRequest, Resp> Resp performRequestAndParseEntity(Req request,
                                                                             CheckedFunction<Req, Request, IOException> requestConverter,
                                                                             RequestOptions options,

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

@@ -0,0 +1,73 @@
+/*
+ * 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.action.ActionListener;
+import org.elasticsearch.protocol.xpack.XPackInfoRequest;
+import org.elasticsearch.protocol.xpack.XPackInfoResponse;
+
+import java.io.IOException;
+
+import static java.util.Collections.emptySet;
+
+/**
+ * A wrapper for the {@link RestHighLevelClient} that provides methods for
+ * accessing the Elastic Licensed X-Pack APIs that are shipped with the
+ * default distribution of Elasticsearch. All of these APIs will 404 if run
+ * against the OSS distribution of Elasticsearch.
+ * <p>
+ * See the <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/xpack-api.html">
+ * X-Pack APIs on elastic.co</a> for more information.
+ */
+public final class XPackClient {
+    private final RestHighLevelClient restHighLevelClient;
+
+    XPackClient(RestHighLevelClient restHighLevelClient) {
+        this.restHighLevelClient = restHighLevelClient;
+    }
+
+    /**
+     * Fetch information about X-Pack from the cluster.
+     * See <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/info-api.html">
+     * the docs</a> for more.
+     * @param request the request
+     * @param options the request options (e.g. headers), use {@link RequestOptions#DEFAULT} if nothing needs to be customized
+     * @return the response
+     * @throws IOException in case there is a problem sending the request or parsing back the response
+     */
+    public XPackInfoResponse info(XPackInfoRequest request, RequestOptions options) throws IOException {
+        return restHighLevelClient.performRequestAndParseEntity(request, RequestConverters::xPackInfo, options,
+            XPackInfoResponse::fromXContent, emptySet());
+    }
+
+    /**
+     * Asynchronously fetch information about X-Pack from the cluster.
+     * See <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/info-api.html">
+     * the docs</a> for more.
+     * @param request the request
+     * @param options the request options (e.g. headers), use {@link RequestOptions#DEFAULT} if nothing needs to be customized
+     * @param listener the listener to be notified upon request completion
+     */
+    public void infoAsync(XPackInfoRequest request, RequestOptions options,
+                                  ActionListener<XPackInfoResponse> listener) {
+        restHighLevelClient.performRequestAsyncAndParseEntity(request, RequestConverters::xPackInfo, options,
+            XPackInfoResponse::fromXContent, listener, emptySet());
+    }
+}

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

@@ -21,10 +21,10 @@
 
 import org.apache.http.client.methods.HttpGet;
 import org.elasticsearch.action.main.MainResponse;
-import org.elasticsearch.protocol.license.LicenseStatus;
 import org.elasticsearch.protocol.xpack.XPackInfoRequest;
 import org.elasticsearch.protocol.xpack.XPackInfoResponse;
 import org.elasticsearch.protocol.xpack.XPackInfoResponse.FeatureSetsInfo.FeatureSet;
+import org.elasticsearch.protocol.xpack.license.LicenseStatus;
 
 import java.io.IOException;
 import java.util.EnumSet;
@@ -60,7 +60,7 @@ public void testXPackInfo() throws IOException {
         XPackInfoRequest request = new XPackInfoRequest();
         request.setCategories(EnumSet.allOf(XPackInfoRequest.Category.class));
         request.setVerbose(true);
-        XPackInfoResponse info = highLevelClient().xPackInfo(request, RequestOptions.DEFAULT);
+        XPackInfoResponse info = highLevelClient().xpack().info(request, RequestOptions.DEFAULT);
 
         MainResponse mainResponse = highLevelClient().info(RequestOptions.DEFAULT);
 
@@ -89,7 +89,7 @@ public void testXPackInfo() throws IOException {
     }
 
     public void testXPackInfoEmptyRequest() throws IOException {
-        XPackInfoResponse info = highLevelClient().xPackInfo(new XPackInfoRequest(), RequestOptions.DEFAULT);
+        XPackInfoResponse info = highLevelClient().xpack().info(new XPackInfoRequest(), RequestOptions.DEFAULT);
 
         /*
          * The default in the transport client is non-verbose and returning

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

@@ -86,7 +86,7 @@ public void testXPackInfo() throws Exception {
                     XPackInfoRequest.Category.BUILD,
                     XPackInfoRequest.Category.LICENSE,
                     XPackInfoRequest.Category.FEATURES));
-            XPackInfoResponse response = client.xPackInfo(request, RequestOptions.DEFAULT);
+            XPackInfoResponse response = client.xpack().info(request, RequestOptions.DEFAULT);
             //end::x-pack-info-execute
 
             //tag::x-pack-info-response
@@ -122,7 +122,7 @@ public void onFailure(Exception e) {
             listener = new LatchedActionListener<>(listener, latch);
 
             // tag::x-pack-info-execute-async
-            client.xPackInfoAsync(request, RequestOptions.DEFAULT, listener); // <1>
+            client.xpack().infoAsync(request, RequestOptions.DEFAULT, listener); // <1>
             // end::x-pack-info-execute-async
 
             assertTrue(latch.await(30L, TimeUnit.SECONDS));

x-pack/plugin/core/src/main/java/org/elasticsearch/license/License.java

@@ -29,7 +29,7 @@
 import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.common.xcontent.XContentType;
-import org.elasticsearch.protocol.license.LicenseStatus;
+import org.elasticsearch.protocol.xpack.license.LicenseStatus;
 
 /**
  * Data structure for license. Use {@link Builder} to build a license.

x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/action/TransportXPackInfoActionTests.java

@@ -10,10 +10,10 @@
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.license.License;
 import org.elasticsearch.license.LicenseService;
-import org.elasticsearch.protocol.license.LicenseStatus;
 import org.elasticsearch.protocol.xpack.XPackInfoRequest;
 import org.elasticsearch.protocol.xpack.XPackInfoResponse;
 import org.elasticsearch.protocol.xpack.XPackInfoResponse.FeatureSetsInfo.FeatureSet;
+import org.elasticsearch.protocol.xpack.license.LicenseStatus;
 import org.elasticsearch.tasks.Task;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.transport.Transport;

x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/datafeed/MlRemoteLicenseChecker.java

@@ -13,9 +13,9 @@
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.util.concurrent.ThreadContext;
 import org.elasticsearch.license.License;
-import org.elasticsearch.protocol.license.LicenseStatus;
 import org.elasticsearch.protocol.xpack.XPackInfoRequest;
 import org.elasticsearch.protocol.xpack.XPackInfoResponse;
+import org.elasticsearch.protocol.xpack.license.LicenseStatus;
 import org.elasticsearch.transport.ActionNotFoundTransportException;
 import org.elasticsearch.transport.RemoteClusterAware;
 import org.elasticsearch.xpack.core.action.XPackInfoAction;

x-pack/plugin/ml/src/test/java/org/elasticsearch/xpack/ml/datafeed/MlRemoteLicenseCheckerTests.java

@@ -11,8 +11,8 @@
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.util.concurrent.ThreadContext;
-import org.elasticsearch.protocol.license.LicenseStatus;
 import org.elasticsearch.protocol.xpack.XPackInfoResponse;
+import org.elasticsearch.protocol.xpack.license.LicenseStatus;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.xpack.core.action.XPackInfoAction;

x-pack/protocol/src/main/java/org/elasticsearch/protocol/xpack/XPackInfoResponse.java

@@ -31,7 +31,7 @@
 import org.elasticsearch.common.xcontent.ToXContentObject;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentParser;
-import org.elasticsearch.protocol.license.LicenseStatus;
+import org.elasticsearch.protocol.xpack.license.LicenseStatus;
 
 import java.io.IOException;
 import java.util.ArrayList;

x-pack/protocol/src/main/java/org/elasticsearch/protocol/license/LicenseStatus.java renamed to x-pack/protocol/src/main/java/org/elasticsearch/protocol/xpack/license/LicenseStatus.java

@@ -16,7 +16,7 @@
  * specific language governing permissions and limitations
  * under the License.
  */
-package org.elasticsearch.protocol.license;
+package org.elasticsearch.protocol.xpack.license;
 
 import java.io.IOException;