Compat/rest controller xpack

modules/rest-compatibility/src/main/java/org/elasticsearch/compat/RestCompatPlugin.java

@@ -19,6 +19,8 @@
 
 package org.elasticsearch.compat;
 
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.elasticsearch.Version;
 import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
 import org.elasticsearch.cluster.node.DiscoveryNodes;
@@ -50,6 +52,7 @@
 import java.util.function.Supplier;
 
 public class RestCompatPlugin extends Plugin implements ActionPlugin {
+    Logger log = LogManager.getLogger(RestCompatPlugin.class);
 
     @Override
     public List<RestHandler> getRestHandlers(

server/src/main/java/org/elasticsearch/action/ActionModule.java

@@ -261,9 +261,11 @@
 import org.elasticsearch.persistent.UpdatePersistentTaskStatusAction;
 import org.elasticsearch.plugins.ActionPlugin;
 import org.elasticsearch.plugins.ActionPlugin.ActionHandler;
+import org.elasticsearch.plugins.RestRequestPlugin;
 import org.elasticsearch.rest.RestController;
 import org.elasticsearch.rest.RestHandler;
 import org.elasticsearch.rest.RestHeaderDefinition;
+import org.elasticsearch.rest.RestRequestFactory;
 import org.elasticsearch.rest.action.RestFieldCapabilitiesAction;
 import org.elasticsearch.rest.action.RestMainAction;
 import org.elasticsearch.rest.action.admin.cluster.RestAddVotingConfigExclusionAction;
@@ -446,7 +448,8 @@ public class ActionModule extends AbstractModule {
     public ActionModule(Settings settings, IndexNameExpressionResolver indexNameExpressionResolver,
                         IndexScopedSettings indexScopedSettings, ClusterSettings clusterSettings, SettingsFilter settingsFilter,
                         ThreadPool threadPool, List<ActionPlugin> actionPlugins, NodeClient nodeClient,
-                        CircuitBreakerService circuitBreakerService, UsageService usageService, ClusterService clusterService) {
+                        CircuitBreakerService circuitBreakerService, UsageService usageService, ClusterService clusterService,
+                        List<RestRequestPlugin> restRequestPlugins) {
         this.settings = settings;
         this.indexNameExpressionResolver = indexNameExpressionResolver;
         this.indexScopedSettings = indexScopedSettings;
@@ -477,10 +480,25 @@ public ActionModule(Settings settings, IndexNameExpressionResolver indexNameExpr
             actionPlugins.stream().flatMap(p -> p.mappingRequestValidators().stream()).collect(Collectors.toList()));
         indicesAliasesRequestRequestValidators = new RequestValidators<>(
                 actionPlugins.stream().flatMap(p -> p.indicesAliasesRequestValidators().stream()).collect(Collectors.toList()));
-
-        restController = new RestController(headers, restWrapper, nodeClient, circuitBreakerService, usageService);
+        RestRequestFactory restRequestFactory = getRestRequestFactory(restRequestPlugins);
+        restController = new RestController(headers, restWrapper, nodeClient, circuitBreakerService, usageService, restRequestFactory);
     }
 
+    private RestRequestFactory getRestRequestFactory(List<RestRequestPlugin> restRequestPlugins) {
+        RestRequestFactory restRequestFactory = null;
+        for (RestRequestPlugin plugin : restRequestPlugins) {
+            RestRequestFactory newRestRequestFactory = plugin.getRestRequestFactory();
+            if (newRestRequestFactory != null) {
+                logger.debug("Using REST request factory from plugin " + plugin.getClass().getName());
+                if (restRequestFactory != null) {
+                    //TODO maybe we could combine/chain them?
+                    throw new IllegalArgumentException("Cannot have more than one plugin implementing a RestRequestPlugin");
+                }
+                restRequestFactory = newRestRequestFactory;
+            }
+        }
+        return restRequestFactory != null ? restRequestFactory : r -> r;
+    }
 
     public Map<String, ActionHandler<?, ?>> getActions() {
         return actions;

server/src/main/java/org/elasticsearch/http/AbstractHttpServerTransport.java

@@ -334,6 +334,7 @@ private void handleIncomingRequest(final HttpRequest httpRequest, final HttpChan
         {
             RestRequest innerRestRequest;
             try {
+                //TODO another option would be to use a factory here, but it requires to modify all the subclasses..
                 innerRestRequest = RestRequest.request(xContentRegistry, httpRequest, httpChannel);
             } catch (final RestRequest.ContentTypeHeaderException e) {
                 badRequestCause = ExceptionsHelper.useOrSuppress(badRequestCause, e);

server/src/main/java/org/elasticsearch/node/Node.java

@@ -141,6 +141,7 @@
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.plugins.PluginsService;
 import org.elasticsearch.plugins.RepositoryPlugin;
+import org.elasticsearch.plugins.RestRequestPlugin;
 import org.elasticsearch.plugins.ScriptPlugin;
 import org.elasticsearch.plugins.SearchPlugin;
 import org.elasticsearch.plugins.SystemIndexPlugin;
@@ -511,7 +512,8 @@ protected Node(final Environment initialEnvironment,
 
             ActionModule actionModule = new ActionModule(settings, clusterModule.getIndexNameExpressionResolver(),
                 settingsModule.getIndexScopedSettings(), settingsModule.getClusterSettings(), settingsModule.getSettingsFilter(),
-                threadPool, pluginsService.filterPlugins(ActionPlugin.class), client, circuitBreakerService, usageService, clusterService);
+                threadPool, pluginsService.filterPlugins(ActionPlugin.class), client, circuitBreakerService, usageService, clusterService,
+                pluginsService.filterPlugins(RestRequestPlugin.class));
             modules.add(actionModule);
 
             final RestController restController = actionModule.getRestController();

server/src/main/java/org/elasticsearch/plugins/ActionPlugin.java

@@ -128,6 +128,8 @@ default UnaryOperator<RestHandler> getRestHandlerWrapper(ThreadContext threadCon
         return null;
     }
 
+//    RestRequestFactory getRestRequestFactory();
+
     final class ActionHandler<Request extends ActionRequest, Response extends ActionResponse> {
         private final ActionType<Response> action;
         private final Class<? extends TransportAction<Request, Response>> transportAction;

server/src/main/java/org/elasticsearch/plugins/RestRequestPlugin.java

@@ -0,0 +1,29 @@
+/*
+ * 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.plugins;
+
+import org.elasticsearch.rest.RestRequestFactory;
+
+public interface RestRequestPlugin {
+    default RestRequestFactory getRestRequestFactory() {
+        return null;
+    }
+
+}

server/src/main/java/org/elasticsearch/rest/RestController.java

@@ -76,11 +76,14 @@ public class RestController implements HttpServerTransport.Dispatcher {
     /** Rest headers that are copied to internal requests made during a rest request. */
     private final Set<RestHeaderDefinition> headersToCopy;
     private final UsageService usageService;
+    private RestRequestFactory restRequestFactory;
 
     public RestController(Set<RestHeaderDefinition> headersToCopy, UnaryOperator<RestHandler> handlerWrapper,
-            NodeClient client, CircuitBreakerService circuitBreakerService, UsageService usageService) {
+                          NodeClient client, CircuitBreakerService circuitBreakerService, UsageService usageService,
+                          RestRequestFactory restRequestFactory) {
         this.headersToCopy = headersToCopy;
         this.usageService = usageService;
+        this.restRequestFactory = restRequestFactory;
         if (handlerWrapper == null) {
             handlerWrapper = h -> h; // passthrough if no wrapper set
         }
@@ -176,8 +179,10 @@ public void dispatchRequest(RestRequest request, RestChannel channel, ThreadCont
             handleFavicon(request.method(), request.uri(), channel);
             return;
         }
+        RestRequest restRequest = restRequestFactory.createRestRequest(request);
+
         try {
-            tryAllHandlers(request, channel, threadContext);
+            tryAllHandlers(restRequest, channel, threadContext);
         } catch (Exception e) {
             try {
                 channel.sendResponse(new BytesRestResponse(channel, e));

server/src/main/java/org/elasticsearch/rest/RestRequest.java

@@ -638,7 +638,7 @@ public static class BadParameterException extends RuntimeException {
 
     public static class CompatibleApiHeadersCombinationException extends RuntimeException {
 
-        CompatibleApiHeadersCombinationException(String cause) {
+        public CompatibleApiHeadersCombinationException(String cause) {
             super(cause);
         }
 

server/src/main/java/org/elasticsearch/rest/RestRequestFactory.java

@@ -0,0 +1,24 @@
+/*
+ * 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.rest;
+
+public interface RestRequestFactory {
+     RestRequest createRestRequest(RestRequest restRequest);
+}

server/src/test/java/org/elasticsearch/action/ActionModuleTests.java

@@ -109,7 +109,7 @@ public void testSetupRestHandlerContainsKnownBuiltin() {
         UsageService usageService = new UsageService();
         ActionModule actionModule = new ActionModule(settings.getSettings(), new IndexNameExpressionResolver(),
                 settings.getIndexScopedSettings(), settings.getClusterSettings(), settings.getSettingsFilter(), null, emptyList(), null,
-                null, usageService, null);
+                null, usageService, null, null);
         actionModule.initRestHandlers(null);
         // At this point the easiest way to confirm that a handler is loaded is to try to register another one on top of it and to fail
         Exception e = expectThrows(IllegalArgumentException.class, () ->
@@ -148,7 +148,7 @@ public String getName() {
             UsageService usageService = new UsageService();
             ActionModule actionModule = new ActionModule(settings.getSettings(), new IndexNameExpressionResolver(),
                     settings.getIndexScopedSettings(), settings.getClusterSettings(), settings.getSettingsFilter(), threadPool,
-                    singletonList(dupsMainAction), null, null, usageService, null);
+                    singletonList(dupsMainAction), null, null, usageService, null, null);
             Exception e = expectThrows(IllegalArgumentException.class, () -> actionModule.initRestHandlers(null));
             assertThat(e.getMessage(), startsWith("Cannot replace existing handler for [/] for method: GET"));
         } finally {
@@ -182,7 +182,7 @@ public List<RestHandler> getRestHandlers(Settings settings, RestController restC
             UsageService usageService = new UsageService();
             ActionModule actionModule = new ActionModule(settings.getSettings(), new IndexNameExpressionResolver(),
                     settings.getIndexScopedSettings(), settings.getClusterSettings(), settings.getSettingsFilter(), threadPool,
-                    singletonList(registersFakeHandler), null, null, usageService, null);
+                    singletonList(registersFakeHandler), null, null, usageService, null, null);
             actionModule.initRestHandlers(null);
             // At this point the easiest way to confirm that a handler is loaded is to try to register another one on top of it and to fail
             Exception e = expectThrows(IllegalArgumentException.class, () ->

server/src/test/java/org/elasticsearch/rest/RestControllerTests.java

@@ -95,7 +95,7 @@ public void setup() {
         inFlightRequestsBreaker = circuitBreakerService.getBreaker(CircuitBreaker.IN_FLIGHT_REQUESTS);
 
         HttpServerTransport httpServerTransport = new TestHttpServerTransport();
-        restController = new RestController(Collections.emptySet(), null, null, circuitBreakerService, usageService);
+        restController = new RestController(Collections.emptySet(), null, null, circuitBreakerService, usageService, r -> r);
         restController.registerHandler(RestRequest.Method.GET, "/",
             (request, channel, client) -> channel.sendResponse(
                 new BytesRestResponse(RestStatus.OK, BytesRestResponse.TEXT_CONTENT_TYPE, BytesArray.EMPTY)));
@@ -110,7 +110,7 @@ public void testApplyRelevantHeaders() throws Exception {
         final ThreadContext threadContext = new ThreadContext(Settings.EMPTY);
         Set<RestHeaderDefinition> headers = new HashSet<>(Arrays.asList(new RestHeaderDefinition("header.1", true),
             new RestHeaderDefinition("header.2", true)));
-        final RestController restController = new RestController(headers, null, null, circuitBreakerService, usageService);
+        final RestController restController = new RestController(headers, null, null, circuitBreakerService, usageService, r -> r);
         Map<String, List<String>> restHeaders = new HashMap<>();
         restHeaders.put("header.1", Collections.singletonList("true"));
         restHeaders.put("header.2", Collections.singletonList("true"));
@@ -146,7 +146,7 @@ public void testRequestWithDisallowedMultiValuedHeader() {
         final ThreadContext threadContext = new ThreadContext(Settings.EMPTY);
         Set<RestHeaderDefinition> headers = new HashSet<>(Arrays.asList(new RestHeaderDefinition("header.1", true),
             new RestHeaderDefinition("header.2", false)));
-        final RestController restController = new RestController(headers, null, null, circuitBreakerService, usageService);
+        final RestController restController = new RestController(headers, null, null, circuitBreakerService, usageService, r -> r);
         Map<String, List<String>> restHeaders = new HashMap<>();
         restHeaders.put("header.1", Collections.singletonList("boo"));
         restHeaders.put("header.2", List.of("foo", "bar"));
@@ -160,7 +160,7 @@ public void testRequestWithDisallowedMultiValuedHeaderButSameValues() {
         final ThreadContext threadContext = new ThreadContext(Settings.EMPTY);
         Set<RestHeaderDefinition> headers = new HashSet<>(Arrays.asList(new RestHeaderDefinition("header.1", true),
             new RestHeaderDefinition("header.2", false)));
-        final RestController restController = new RestController(headers, null, null, circuitBreakerService, usageService);
+        final RestController restController = new RestController(headers, null, null, circuitBreakerService, usageService, r -> r);
         Map<String, List<String>> restHeaders = new HashMap<>();
         restHeaders.put("header.1", Collections.singletonList("boo"));
         restHeaders.put("header.2", List.of("foo", "foo"));
@@ -214,7 +214,7 @@ public void testRegisterWithDeprecatedHandler() {
     }
 
     public void testRegisterSecondMethodWithDifferentNamedWildcard() {
-        final RestController restController = new RestController(null, null, null, circuitBreakerService, usageService);
+        final RestController restController = new RestController(null, null, null, circuitBreakerService, usageService, r -> r);
 
         RestRequest.Method firstMethod = randomFrom(RestRequest.Method.values());
         RestRequest.Method secondMethod =
@@ -247,7 +247,7 @@ public void testRestHandlerWrapper() throws Exception {
                 h -> {
                     assertSame(handler, h);
                     return (RestRequest request, RestChannel channel, NodeClient client) -> wrapperCalled.set(true);
-                }, null, circuitBreakerService, usageService);
+                }, null, circuitBreakerService, usageService, r -> r);
         restController.registerHandler(RestRequest.Method.GET, "/wrapped", handler);
         RestRequest request = testRestRequest("/wrapped", "{}", XContentType.JSON);
         AssertingChannel channel = new AssertingChannel(request, true, RestStatus.BAD_REQUEST);
@@ -310,7 +310,7 @@ public void testDispatchRequiresContentTypeForRequestsWithContent() {
         String content = randomAlphaOfLength((int) Math.round(BREAKER_LIMIT.getBytes() / inFlightRequestsBreaker.getOverhead()));
         RestRequest request = testRestRequest("/", content, null);
         AssertingChannel channel = new AssertingChannel(request, true, RestStatus.NOT_ACCEPTABLE);
-        restController = new RestController(Collections.emptySet(), null, null, circuitBreakerService, usageService);
+        restController = new RestController(Collections.emptySet(), null, null, circuitBreakerService, usageService, r -> r);
         restController.registerHandler(RestRequest.Method.GET, "/",
             (r, c, client) -> c.sendResponse(
                 new BytesRestResponse(RestStatus.OK, BytesRestResponse.TEXT_CONTENT_TYPE, BytesArray.EMPTY)));

server/src/test/java/org/elasticsearch/rest/RestHttpResponseHeadersTests.java

@@ -90,7 +90,7 @@ public void testUnsupportedMethodResponseHttpHeader() throws Exception {
         final Settings settings = Settings.EMPTY;
         UsageService usageService = new UsageService();
         RestController restController = new RestController(Collections.emptySet(),
-                null, null, circuitBreakerService, usageService);
+                null, null, circuitBreakerService, usageService, r -> r);
 
         // A basic RestHandler handles requests to the endpoint
         RestHandler restHandler = new RestHandler() {

server/src/test/java/org/elasticsearch/rest/action/admin/indices/RestValidateQueryActionTests.java

@@ -58,7 +58,7 @@ public class RestValidateQueryActionTests extends AbstractSearchTestCase {
 
     private static UsageService usageService = new UsageService();
     private static RestController controller = new RestController(emptySet(), null, client,
-        new NoneCircuitBreakerService(), usageService);
+        new NoneCircuitBreakerService(), usageService, r -> r);
     private static RestValidateQueryAction action = new RestValidateQueryAction();
 
     /**

test/framework/src/main/java/org/elasticsearch/test/rest/RestActionTestCase.java

@@ -47,7 +47,7 @@ public void setUpController() {
         controller = new RestController(Collections.emptySet(), null,
             nodeClient,
             new NoneCircuitBreakerService(),
-            new UsageService());
+            new UsageService(), r -> r);
     }
 
     /**

x-pack/plugin/rest-compat/build.gradle

@@ -0,0 +1,18 @@
+evaluationDependsOn(xpackModule('core'))
+
+apply plugin: 'elasticsearch.esplugin'
+
+esplugin {
+  name 'rest-compat'
+  description 'A plugin for Rest compat request features'
+  classname 'org.elasticsearch.compat.RestCompatRequestPlugin'
+  extendedPlugins = ['x-pack-core']
+}
+
+dependencies {
+  compileOnly project(path: xpackModule('core'), configuration: 'default')
+  testImplementation project(path: xpackModule('core'), configuration: 'testArtifacts')
+}
+
+
+integTest.enabled = false