Move tribe to a module (elastic#25778)

This commit moves tribe to a module, stripping core from the tribe functionality.

buildSrc/src/main/resources/checkstyle_suppressions.xml

@@ -417,7 +417,7 @@
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]snapshots[/\\]SnapshotShardsService.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]snapshots[/\\]SnapshotsService.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]threadpool[/\\]ThreadPool.java" checks="LineLength" />
-  <suppress files="core[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]tribe[/\\]TribeService.java" checks="LineLength" />
+  <suppress files="modules[/\\]tribe[/\\]src[/\\]main[/\\]java[/\\]org[/\\]elasticsearch[/\\]tribe[/\\]TribeService.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]apache[/\\]lucene[/\\]queries[/\\]BlendedTermQueryTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]VersionTests.java" checks="LineLength" />
   <suppress files="core[/\\]src[/\\]test[/\\]java[/\\]org[/\\]elasticsearch[/\\]action[/\\]RejectionActionIT.java" checks="LineLength" />

core/src/main/java/org/elasticsearch/cluster/ClusterModule.java

@@ -94,6 +94,7 @@ public class ClusterModule extends AbstractModule {
     private final IndexNameExpressionResolver indexNameExpressionResolver;
     private final AllocationDeciders allocationDeciders;
     private final AllocationService allocationService;
+    private final Runnable onStarted;
     // pkg private for tests
     final Collection<AllocationDecider> deciderList;
     final ShardsAllocator shardsAllocator;
@@ -106,6 +107,7 @@ public ClusterModule(Settings settings, ClusterService clusterService, List<Clus
         this.clusterService = clusterService;
         this.indexNameExpressionResolver = new IndexNameExpressionResolver(settings);
         this.allocationService = new AllocationService(settings, allocationDeciders, shardsAllocator, clusterInfoService);
+        this.onStarted = () -> clusterPlugins.forEach(plugin -> plugin.onNodeStarted());
     }
 
 
@@ -241,4 +243,8 @@ protected void configure() {
         bind(AllocationDeciders.class).toInstance(allocationDeciders);
         bind(ShardsAllocator.class).toInstance(shardsAllocator);
     }
+
+    public Runnable onStarted() {
+        return onStarted;
+    }
 }

core/src/main/java/org/elasticsearch/cluster/MergableCustomMetaData.java

@@ -0,0 +1,43 @@
+/*
+ * 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.cluster;
+
+import org.elasticsearch.cluster.metadata.MetaData;
+
+/**
+ * Interface to allow merging {@link org.elasticsearch.cluster.metadata.MetaData.Custom}.
+ * When multiple Mergable Custom metadata of the same type are found (from underlying clusters), the
+ * Custom metadata can be merged using {@link #merge(MetaData.Custom)}.
+ *
+ * @param <T> type of custom meta data
+ */
+public interface MergableCustomMetaData<T extends MetaData.Custom> {
+
+    /**
+     * Merges this custom metadata with other, returning either this or <code>other</code> custom metadata.
+     * This method should not mutate either <code>this</code> or the <code>other</code> custom metadata.
+     *
+     * @param other custom meta data
+     * @return the same instance or <code>other</code> custom metadata based on implementation
+     *         if both the instances are considered equal, implementations should return this
+     *         instance to avoid redundant cluster state changes.
+     */
+    T merge(T other);
+}

core/src/main/java/org/elasticsearch/common/settings/ClusterSettings.java

@@ -71,7 +71,6 @@
 import org.elasticsearch.indices.fielddata.cache.IndicesFieldDataCache;
 import org.elasticsearch.indices.recovery.RecoverySettings;
 import org.elasticsearch.indices.store.IndicesStore;
-import org.elasticsearch.ingest.IngestService;
 import org.elasticsearch.monitor.fs.FsService;
 import org.elasticsearch.monitor.jvm.JvmGcMonitorService;
 import org.elasticsearch.monitor.jvm.JvmService;
@@ -91,7 +90,6 @@
 import org.elasticsearch.transport.TcpTransport;
 import org.elasticsearch.transport.Transport;
 import org.elasticsearch.transport.TransportService;
-import org.elasticsearch.tribe.TribeService;
 import org.elasticsearch.watcher.ResourceWatcherService;
 
 import java.util.Arrays;
@@ -369,13 +367,6 @@ public void apply(Settings value, Settings current, Settings previous) {
                     ThreadContext.DEFAULT_HEADERS_SETTING,
                     ESLoggerFactory.LOG_DEFAULT_LEVEL_SETTING,
                     ESLoggerFactory.LOG_LEVEL_SETTING,
-                    TribeService.BLOCKS_METADATA_SETTING,
-                    TribeService.BLOCKS_WRITE_SETTING,
-                    TribeService.BLOCKS_WRITE_INDICES_SETTING,
-                    TribeService.BLOCKS_READ_INDICES_SETTING,
-                    TribeService.BLOCKS_METADATA_INDICES_SETTING,
-                    TribeService.ON_CONFLICT_SETTING,
-                    TribeService.TRIBE_NAME_SETTING,
                     NodeEnvironment.MAX_LOCAL_STORAGE_NODES_SETTING,
                     NodeEnvironment.ENABLE_LUCENE_SEGMENT_INFOS_TRACE_SETTING,
                     OsService.REFRESH_INTERVAL_SETTING,

core/src/main/java/org/elasticsearch/common/settings/SettingsModule.java

@@ -26,7 +26,6 @@
 import org.elasticsearch.common.xcontent.ToXContent;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentType;
-import org.elasticsearch.tribe.TribeService;
 
 import java.io.IOException;
 import java.util.Arrays;
@@ -49,8 +48,6 @@ public class SettingsModule implements Module {
     private final Set<String> settingsFilterPattern = new HashSet<>();
     private final Map<String, Setting<?>> nodeSettings = new HashMap<>();
     private final Map<String, Setting<?>> indexSettings = new HashMap<>();
-    private static final Predicate<String> TRIBE_CLIENT_NODE_SETTINGS_PREDICATE =  (s) -> s.startsWith("tribe.")
-        && TribeService.TRIBE_SETTING_KEYS.contains(s) == false;
     private final Logger logger;
     private final IndexScopedSettings indexScopedSettings;
     private final ClusterSettings clusterSettings;
@@ -135,9 +132,7 @@ public SettingsModule(Settings settings, List<Setting<?>> additionalSettings, Li
             }
         }
         // by now we are fully configured, lets check node level settings for unregistered index settings
-        final Predicate<String> acceptOnlyClusterSettings = TRIBE_CLIENT_NODE_SETTINGS_PREDICATE.negate();
-        clusterSettings.validate(settings.filter(acceptOnlyClusterSettings));
-        validateTribeSettings(settings, clusterSettings);
+        clusterSettings.validate(settings);
         this.settingsFilter = new SettingsFilter(settings, settingsFilterPattern);
      }
 
@@ -195,20 +190,6 @@ private void registerSettingsFilter(String filter) {
         settingsFilterPattern.add(filter);
     }
 
-    private void validateTribeSettings(Settings settings, ClusterSettings clusterSettings) {
-        Map<String, Settings> groups = settings.filter(TRIBE_CLIENT_NODE_SETTINGS_PREDICATE).getGroups("tribe.", true);
-        for (Map.Entry<String, Settings>  tribeSettings : groups.entrySet()) {
-            Settings thisTribesSettings = tribeSettings.getValue();
-            for (Map.Entry<String, String> entry : thisTribesSettings.getAsMap().entrySet()) {
-                try {
-                    clusterSettings.validate(entry.getKey(), thisTribesSettings);
-                } catch (IllegalArgumentException ex) {
-                    throw new IllegalArgumentException("tribe." + tribeSettings.getKey() +" validation failed: "+ ex.getMessage(), ex);
-                }
-            }
-        }
-    }
-
     public Settings getSettings() {
         return settings;
     }

core/src/main/java/org/elasticsearch/discovery/DiscoveryModule.java

@@ -86,7 +86,6 @@ public DiscoveryModule(Settings settings, ThreadPool threadPool, TransportServic
         discoveryTypes.put("zen",
             () -> new ZenDiscovery(settings, threadPool, transportService, namedWriteableRegistry, masterService, clusterApplier,
                 clusterSettings, hostsProvider, allocationService));
-        discoveryTypes.put("tribe", () -> new TribeDiscovery(settings, transportService, masterService, clusterApplier));
         discoveryTypes.put("single-node", () -> new SingleNodeDiscovery(settings, transportService, masterService, clusterApplier));
         for (DiscoveryPlugin plugin : plugins) {
             plugin.getDiscoveryTypes(threadPool, transportService, namedWriteableRegistry,

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

@@ -133,7 +133,6 @@
 import org.elasticsearch.transport.Transport;
 import org.elasticsearch.transport.TransportInterceptor;
 import org.elasticsearch.transport.TransportService;
-import org.elasticsearch.tribe.TribeService;
 import org.elasticsearch.usage.UsageService;
 import org.elasticsearch.watcher.ResourceWatcherService;
 
@@ -256,8 +255,6 @@ protected Node(final Environment environment, Collection<Class<? extends Plugin>
             Settings tmpSettings = Settings.builder().put(environment.settings())
                 .put(Client.CLIENT_TYPE_SETTING_S.getKey(), CLIENT_TYPE).build();
 
-            tmpSettings = TribeService.processSettings(tmpSettings);
-
             // create the node environment as soon as possible, to recover the node id and enable logging
             try {
                 nodeEnvironment = new NodeEnvironment(tmpSettings, environment);
@@ -385,15 +382,6 @@ protected Node(final Environment environment, Collection<Class<? extends Plugin>
                     .flatMap(p -> p.getNamedXContent().stream()),
                 ClusterModule.getNamedXWriteables().stream())
                 .flatMap(Function.identity()).collect(toList()));
-            final TribeService tribeService =
-                    new TribeService(
-                            settings,
-                            environment.configFile(),
-                            clusterService,
-                            nodeId,
-                            namedWriteableRegistry,
-                            (s, p) -> newTribeClientNode(s, classpathPlugins, p));
-            resourcesToClose.add(tribeService);
             modules.add(new RepositoriesModule(this.environment, pluginsService.filterPlugins(RepositoryPlugin.class), xContentRegistry));
             final MetaStateService metaStateService = new MetaStateService(settings, nodeEnvironment, xContentRegistry);
             final IndicesService indicesService = new IndicesService(settings, pluginsService, nodeEnvironment, xContentRegistry,
@@ -404,7 +392,8 @@ protected Node(final Environment environment, Collection<Class<? extends Plugin>
 
             Collection<Object> pluginComponents = pluginsService.filterPlugins(Plugin.class).stream()
                 .flatMap(p -> p.createComponents(client, clusterService, threadPool, resourceWatcherService,
-                                                 scriptModule.getScriptService(), xContentRegistry).stream())
+                                                 scriptModule.getScriptService(), xContentRegistry, environment, nodeEnvironment,
+                                                 namedWriteableRegistry).stream())
                 .collect(Collectors.toList());
             final RestController restController = actionModule.getRestController();
             final NetworkModule networkModule = new NetworkModule(settings, false, pluginsService.filterPlugins(NetworkPlugin.class),
@@ -458,7 +447,6 @@ protected Node(final Environment environment, Collection<Class<? extends Plugin>
                     b.bind(Environment.class).toInstance(this.environment);
                     b.bind(ThreadPool.class).toInstance(threadPool);
                     b.bind(NodeEnvironment.class).toInstance(nodeEnvironment);
-                    b.bind(TribeService.class).toInstance(tribeService);
                     b.bind(ResourceWatcherService.class).toInstance(resourceWatcherService);
                     b.bind(CircuitBreakerService.class).toInstance(circuitBreakerService);
                     b.bind(BigArrays.class).toInstance(bigArrays);
@@ -612,10 +600,6 @@ public Node start() throws NodeValidationException {
         Discovery discovery = injector.getInstance(Discovery.class);
         clusterService.getMasterService().setClusterStatePublisher(discovery::publish);
 
-        // start before the cluster service since it adds/removes initial Cluster state blocks
-        final TribeService tribeService = injector.getInstance(TribeService.class);
-        tribeService.start();
-
         // Start the transport service now so the publish address will be added to the local disco node in ClusterService
         TransportService transportService = injector.getInstance(TransportService.class);
         transportService.getTaskManager().setTaskResultsService(injector.getInstance(TaskResultsService.class));
@@ -682,10 +666,10 @@ public void onTimeout(TimeValue timeout) {
             writePortsFile("transport", transport.boundAddress());
         }
 
-        // start nodes now, after the http server, because it may take some time
-        tribeService.startNodes();
         logger.info("started");
 
+        pluginsService.filterPlugins(ClusterPlugin.class).forEach(ClusterPlugin::onNodeStarted);
+
         return this;
     }
 
@@ -696,7 +680,6 @@ private Node stop() {
         Logger logger = Loggers.getLogger(Node.class, NODE_NAME_SETTING.get(settings));
         logger.info("stopping ...");
 
-        injector.getInstance(TribeService.class).stop();
         injector.getInstance(ResourceWatcherService.class).stop();
         if (NetworkModule.HTTP_ENABLED.get(settings)) {
             injector.getInstance(HttpServerTransport.class).stop();
@@ -744,7 +727,6 @@ public synchronized void close() throws IOException {
         List<Closeable> toClose = new ArrayList<>();
         StopWatch stopWatch = new StopWatch("node_close");
         toClose.add(() -> stopWatch.start("tribe"));
-        toClose.add(injector.getInstance(TribeService.class));
         toClose.add(() -> stopWatch.stop().start("node_service"));
         toClose.add(nodeService);
         toClose.add(() -> stopWatch.stop().start("http"));
@@ -920,11 +902,6 @@ private List<NetworkService.CustomNameResolver> getCustomNameResolvers(List<Disc
         return customNameResolvers;
     }
 
-    /** Constructs an internal node used as a client into a cluster fronted by this tribe node. */
-    protected Node newTribeClientNode(Settings settings, Collection<Class<? extends Plugin>> classpathPlugins, Path configPath) {
-        return new Node(new Environment(settings, configPath), classpathPlugins);
-    }
-
     /** Constructs a ClusterInfoService which may be mocked for tests. */
     protected ClusterInfoService newClusterInfoService(Settings settings, ClusterService clusterService,
                                                        ThreadPool threadPool, NodeClient client, Consumer<ClusterInfo> listeners) {

core/src/main/java/org/elasticsearch/plugins/ClusterPlugin.java

@@ -58,4 +58,11 @@ default Collection<AllocationDecider> createAllocationDeciders(Settings settings
     default Map<String, Supplier<ShardsAllocator>> getShardsAllocators(Settings settings, ClusterSettings clusterSettings) {
         return Collections.emptyMap();
     }
+
+    /**
+     * Called when the node is started
+     */
+    default void onNodeStarted() {
+
+    }
 }

core/src/main/java/org/elasticsearch/plugins/Plugin.java

@@ -38,6 +38,8 @@
 import org.elasticsearch.common.xcontent.NamedXContentRegistry;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.discovery.DiscoveryModule;
+import org.elasticsearch.env.Environment;
+import org.elasticsearch.env.NodeEnvironment;
 import org.elasticsearch.index.IndexModule;
 import org.elasticsearch.indices.analysis.AnalysisModule;
 import org.elasticsearch.repositories.RepositoriesModule;
@@ -104,10 +106,15 @@ public Collection<Class<? extends LifecycleComponent>> getGuiceServiceClasses()
      * @param threadPool A service to allow retrieving an executor to run an async action
      * @param resourceWatcherService A service to watch for changes to node local files
      * @param scriptService A service to allow running scripts on the local node
+     * @param xContentRegistry the registry for extensible xContent parsing
+     * @param environment the environment for path and setting configurations
+     * @param nodeEnvironment the node environment used coordinate access to the data paths
+     * @param namedWriteableRegistry the registry for {@link NamedWriteable} object parsing
      */
     public Collection<Object> createComponents(Client client, ClusterService clusterService, ThreadPool threadPool,
                                                ResourceWatcherService resourceWatcherService, ScriptService scriptService,
-                                               NamedXContentRegistry xContentRegistry) {
+                                               NamedXContentRegistry xContentRegistry, Environment environment,
+                                               NodeEnvironment nodeEnvironment, NamedWriteableRegistry namedWriteableRegistry) {
         return Collections.emptyList();
     }
 

core/src/test/java/org/elasticsearch/cluster/metadata/TemplateUpgradeServiceIT.java

@@ -22,10 +22,13 @@
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.client.Client;
 import org.elasticsearch.cluster.service.ClusterService;
+import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
 import org.elasticsearch.common.logging.Loggers;
 import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.NamedXContentRegistry;
+import org.elasticsearch.env.Environment;
+import org.elasticsearch.env.NodeEnvironment;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.script.ScriptService;
 import org.elasticsearch.test.ESIntegTestCase;
@@ -67,11 +70,13 @@ public TestPlugin(Settings settings) {
         @Override
         public Collection<Object> createComponents(Client client, ClusterService clusterService, ThreadPool threadPool,
                                                    ResourceWatcherService resourceWatcherService, ScriptService scriptService,
-                                                   NamedXContentRegistry xContentRegistry) {
+                                                   NamedXContentRegistry xContentRegistry, Environment environment,
+                                                   NodeEnvironment nodeEnvironment, NamedWriteableRegistry namedWriteableRegistry) {
             clusterService.getClusterSettings().addSettingsUpdateConsumer(UPDATE_TEMPLATE_DUMMY_SETTING, integer -> {
                 logger.debug("the template dummy setting was updated to {}", integer);
             });
-            return super.createComponents(client, clusterService, threadPool, resourceWatcherService, scriptService, xContentRegistry);
+            return super.createComponents(client, clusterService, threadPool, resourceWatcherService, scriptService, xContentRegistry,
+                environment, nodeEnvironment, namedWriteableRegistry);
         }
 
         @Override