Remove IndexStore and DirectoryService (#42446)

Both of these classes are basically a bloated wrapper around a simple
construct that can simply be a DirectoryFactory interface. This change
removes both classes and replaces them with a simple stateless interface
that creates a new `Directory` per shard. The concept of `index.store` is preserved
since it makes sense from a configuration perspective.

docs/reference/migration/migrate_7_3.asciidoc

@@ -0,0 +1,28 @@
+[[breaking-changes-7.3]]
+== Breaking changes in 7.3
+++++
+<titleabbrev>7.3</titleabbrev>
+++++
+
+This section discusses the changes that you need to be aware of when migrating
+your application to Elasticsearch 7.3.
+
+See also <<release-highlights>> and <<es-release-notes>>.
+
+coming[7.3.0]
+
+//NOTE: The notable-breaking-changes tagged regions are re-used in the
+//Installation and Upgrade Guide
+
+//tag::notable-breaking-changes[]
+
+// end::notable-breaking-changes[]
+
+[[breaking_73_plugin_changes]]
+=== Plugins changes
+
+[float]
+==== IndexStorePlugin changes
+
+IndexStore and DirectoryService have been replaced by a stateless and simple
+DirectoryFactory interface to create custom Lucene directory instances per shard.

plugins/store-smb/src/main/java/org/elasticsearch/index/store/smbmmapfs/SmbMmapFsDirectoryFactory.java

@@ -23,22 +23,16 @@ import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.LockFactory;
 import org.apache.lucene.store.MMapDirectory;
 import org.elasticsearch.index.IndexSettings;
-import org.elasticsearch.index.shard.ShardPath;
+import org.elasticsearch.index.store.FsDirectoryFactory;
-import org.elasticsearch.index.store.FsDirectoryService;
 import org.elasticsearch.index.store.SmbDirectoryWrapper;
 
 import java.io.IOException;
 import java.nio.file.Path;
 
-public class SmbMmapFsDirectoryService extends FsDirectoryService {
+public final class SmbMmapFsDirectoryFactory extends FsDirectoryFactory {
-
-    public SmbMmapFsDirectoryService(IndexSettings indexSettings, ShardPath path) {
-        super(indexSettings, path);
-    }
 
     @Override
-    protected Directory newFSDirectory(Path location, LockFactory lockFactory) throws IOException {
+    protected Directory newFSDirectory(Path location, LockFactory lockFactory, IndexSettings indexSettings) throws IOException {
-        logger.debug("wrapping MMapDirectory for SMB");
+        return new SmbDirectoryWrapper(new MMapDirectory(location, lockFactory));
-        return new SmbDirectoryWrapper(new MMapDirectory(location, indexSettings.getValue(INDEX_LOCK_FACTOR_SETTING)));
     }
 }

plugins/store-smb/src/main/java/org/elasticsearch/index/store/smbmmapfs/SmbMmapFsIndexStore.java

@@ -1,37 +0,0 @@
-/*
- * 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.index.store.smbmmapfs;
-
-import org.elasticsearch.index.IndexSettings;
-import org.elasticsearch.index.shard.ShardPath;
-import org.elasticsearch.index.store.DirectoryService;
-import org.elasticsearch.index.store.IndexStore;
-
-public class SmbMmapFsIndexStore extends IndexStore {
-
-    public SmbMmapFsIndexStore(IndexSettings indexSettings) {
-        super(indexSettings);
-    }
-
-    @Override
-    public DirectoryService newDirectoryService(ShardPath path) {
-        return new SmbMmapFsDirectoryService(indexSettings, path);
-    }
-}

plugins/store-smb/src/main/java/org/elasticsearch/index/store/smbsimplefs/SmbSimpleFsDirectoryFactory.java

@@ -23,22 +23,16 @@ import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.LockFactory;
 import org.apache.lucene.store.SimpleFSDirectory;
 import org.elasticsearch.index.IndexSettings;
-import org.elasticsearch.index.shard.ShardPath;
+import org.elasticsearch.index.store.FsDirectoryFactory;
-import org.elasticsearch.index.store.FsDirectoryService;
 import org.elasticsearch.index.store.SmbDirectoryWrapper;
 
 import java.io.IOException;
 import java.nio.file.Path;
 
-public class SmbSimpleFsDirectoryService extends FsDirectoryService {
+public final class SmbSimpleFsDirectoryFactory extends FsDirectoryFactory {
-
-    public SmbSimpleFsDirectoryService(IndexSettings indexSettings, ShardPath path) {
-        super(indexSettings, path);
-    }
 
     @Override
-    protected Directory newFSDirectory(Path location, LockFactory lockFactory) throws IOException {
+    protected Directory newFSDirectory(Path location, LockFactory lockFactory, IndexSettings indexSettings) throws IOException {
-        logger.debug("wrapping SimpleFSDirectory for SMB");
         return new SmbDirectoryWrapper(new SimpleFSDirectory(location, lockFactory));
     }
 }

plugins/store-smb/src/main/java/org/elasticsearch/index/store/smbsimplefs/SmbSimpleFsIndexStore.java

@@ -1,38 +0,0 @@
-/*
- * 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.index.store.smbsimplefs;
-
-import org.elasticsearch.index.IndexSettings;
-import org.elasticsearch.index.shard.ShardPath;
-import org.elasticsearch.index.store.DirectoryService;
-import org.elasticsearch.index.store.IndexStore;
-
-public class SmbSimpleFsIndexStore extends IndexStore {
-
-    public SmbSimpleFsIndexStore(IndexSettings indexSettings) {
-        super(indexSettings);
-    }
-
-    @Override
-    public DirectoryService newDirectoryService(ShardPath path) {
-        return new SmbSimpleFsDirectoryService(indexSettings, path);
-    }
-}
-

plugins/store-smb/src/main/java/org/elasticsearch/plugin/store/smb/SMBStorePlugin.java

@@ -19,25 +19,22 @@
 
 package org.elasticsearch.plugin.store.smb;
 
-import org.elasticsearch.index.IndexSettings;
+import org.elasticsearch.index.store.smbmmapfs.SmbMmapFsDirectoryFactory;
-import org.elasticsearch.index.store.IndexStore;
+import org.elasticsearch.index.store.smbsimplefs.SmbSimpleFsDirectoryFactory;
-import org.elasticsearch.index.store.smbmmapfs.SmbMmapFsIndexStore;
-import org.elasticsearch.index.store.smbsimplefs.SmbSimpleFsIndexStore;
 import org.elasticsearch.plugins.IndexStorePlugin;
 import org.elasticsearch.plugins.Plugin;
 
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
-import java.util.function.Function;
 
 public class SMBStorePlugin extends Plugin implements IndexStorePlugin {
 
     @Override
-    public Map<String, Function<IndexSettings, IndexStore>> getIndexStoreFactories() {
+    public Map<String, DirectoryFactory> getDirectoryFactories() {
-        final Map<String, Function<IndexSettings, IndexStore>> indexStoreFactories = new HashMap<>(2);
+        final Map<String, DirectoryFactory> indexStoreFactories = new HashMap<>(2);
-        indexStoreFactories.put("smb_mmap_fs", SmbMmapFsIndexStore::new);
+        indexStoreFactories.put("smb_mmap_fs", new SmbMmapFsDirectoryFactory());
-        indexStoreFactories.put("smb_simple_fs", SmbSimpleFsIndexStore::new);
+        indexStoreFactories.put("smb_simple_fs", new SmbSimpleFsDirectoryFactory());
         return Collections.unmodifiableMap(indexStoreFactories);
     }
 

server/src/main/java/org/elasticsearch/common/settings/IndexScopedSettings.java

@@ -38,7 +38,7 @@ import org.elasticsearch.index.fielddata.IndexFieldDataService;
 import org.elasticsearch.index.mapper.FieldMapper;
 import org.elasticsearch.index.mapper.MapperService;
 import org.elasticsearch.index.similarity.SimilarityService;
-import org.elasticsearch.index.store.FsDirectoryService;
+import org.elasticsearch.index.store.FsDirectoryFactory;
 import org.elasticsearch.index.store.Store;
 import org.elasticsearch.indices.IndicesRequestCache;
 
@@ -159,7 +159,7 @@ public final class IndexScopedSettings extends AbstractScopedSettings {
         IndexModule.INDEX_STORE_TYPE_SETTING,
         IndexModule.INDEX_STORE_PRE_LOAD_SETTING,
         IndexModule.INDEX_QUERY_CACHE_ENABLED_SETTING,
-        FsDirectoryService.INDEX_LOCK_FACTOR_SETTING,
+        FsDirectoryFactory.INDEX_LOCK_FACTOR_SETTING,
         Store.FORCE_RAM_TERM_DICT,
         EngineConfig.INDEX_CODEC_SETTING,
         EngineConfig.INDEX_OPTIMIZE_AUTO_GENERATED_IDS,

server/src/main/java/org/elasticsearch/env/NodeEnvironment.java

@@ -52,7 +52,7 @@ import org.elasticsearch.index.Index;
 import org.elasticsearch.index.IndexSettings;
 import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.index.shard.ShardPath;
-import org.elasticsearch.index.store.FsDirectoryService;
+import org.elasticsearch.index.store.FsDirectoryFactory;
 import org.elasticsearch.monitor.fs.FsInfo;
 import org.elasticsearch.monitor.fs.FsProbe;
 import org.elasticsearch.monitor.jvm.JvmInfo;
@@ -469,7 +469,7 @@ public final class NodeEnvironment  implements Closeable {
                 // resolve the directory the shard actually lives in
                 Path p = shardPaths[i].resolve("index");
                 // open a directory (will be immediately closed) on the shard's location
-                dirs[i] = new SimpleFSDirectory(p, indexSettings.getValue(FsDirectoryService.INDEX_LOCK_FACTOR_SETTING));
+                dirs[i] = new SimpleFSDirectory(p, indexSettings.getValue(FsDirectoryFactory.INDEX_LOCK_FACTOR_SETTING));
                 // create a lock for the "write.lock" file
                 try {
                     locks[i] = dirs[i].obtainLock(IndexWriter.WRITE_LOCK_NAME);

server/src/main/java/org/elasticsearch/index/IndexModule.java

@@ -45,7 +45,8 @@ import org.elasticsearch.index.shard.IndexSearcherWrapper;
 import org.elasticsearch.index.shard.IndexingOperationListener;
 import org.elasticsearch.index.shard.SearchOperationListener;
 import org.elasticsearch.index.similarity.SimilarityService;
-import org.elasticsearch.index.store.IndexStore;
+import org.elasticsearch.index.store.DirectoryService;
+import org.elasticsearch.index.store.FsDirectoryFactory;
 import org.elasticsearch.indices.IndicesQueryCache;
 import org.elasticsearch.indices.breaker.CircuitBreakerService;
 import org.elasticsearch.indices.fielddata.cache.IndicesFieldDataCache;
@@ -75,7 +76,7 @@ import java.util.function.Function;
  *     {@link #addSimilarity(String, TriFunction)} while existing Providers can be referenced through Settings under the
  *     {@link IndexModule#SIMILARITY_SETTINGS_PREFIX} prefix along with the "type" value.  For example, to reference the
  *     {@link BM25Similarity}, the configuration {@code "index.similarity.my_similarity.type : "BM25"} can be used.</li>
- *      <li>{@link IndexStore} - Custom {@link IndexStore} instances can be registered via {@link IndexStorePlugin}</li>
+ *      <li>{@link DirectoryService} - Custom {@link DirectoryService} instances can be registered via {@link IndexStorePlugin}</li>
  *      <li>{@link IndexEventListener} - Custom {@link IndexEventListener} instances can be registered via
  *      {@link #addIndexEventListener(IndexEventListener)}</li>
  *      <li>Settings update listener - Custom settings update listener can be registered via
@@ -86,6 +87,8 @@ public final class IndexModule {
 
     public static final Setting<Boolean> NODE_STORE_ALLOW_MMAP = Setting.boolSetting("node.store.allow_mmap", true, Property.NodeScope);
 
+    private static final FsDirectoryFactory DEFAULT_DIRECTORY_FACTORY = new FsDirectoryFactory();
+
     public static final Setting<String> INDEX_STORE_TYPE_SETTING =
             new Setting<>("index.store.type", "", Function.identity(), Property.IndexScope, Property.NodeScope);
 
@@ -112,7 +115,7 @@ public final class IndexModule {
     private SetOnce<IndexSearcherWrapperFactory> indexSearcherWrapper = new SetOnce<>();
     private final Set<IndexEventListener> indexEventListeners = new HashSet<>();
     private final Map<String, TriFunction<Settings, Version, ScriptService, Similarity>> similarities = new HashMap<>();
-    private final Map<String, Function<IndexSettings, IndexStore>> indexStoreFactories;
+    private final Map<String, IndexStorePlugin.DirectoryFactory> directoryFactories;
     private final SetOnce<BiFunction<IndexSettings, IndicesQueryCache, QueryCache>> forceQueryCacheProvider = new SetOnce<>();
     private final List<SearchOperationListener> searchOperationListeners = new ArrayList<>();
     private final List<IndexingOperationListener> indexOperationListeners = new ArrayList<>();
@@ -125,19 +128,19 @@ public final class IndexModule {
      * @param indexSettings       the index settings
      * @param analysisRegistry    the analysis registry
      * @param engineFactory       the engine factory
-     * @param indexStoreFactories the available store types
+     * @param directoryFactories the available store types
      */
     public IndexModule(
             final IndexSettings indexSettings,
             final AnalysisRegistry analysisRegistry,
             final EngineFactory engineFactory,
-            final Map<String, Function<IndexSettings, IndexStore>> indexStoreFactories) {
+            final Map<String, IndexStorePlugin.DirectoryFactory> directoryFactories) {
         this.indexSettings = indexSettings;
         this.analysisRegistry = analysisRegistry;
         this.engineFactory = Objects.requireNonNull(engineFactory);
         this.searchOperationListeners.add(new SearchSlowLog(indexSettings));
         this.indexOperationListeners.add(new IndexingSlowLog(indexSettings));
-        this.indexStoreFactories = Collections.unmodifiableMap(indexStoreFactories);
+        this.directoryFactories = Collections.unmodifiableMap(directoryFactories);
     }
 
     /**
@@ -384,7 +387,7 @@ public final class IndexModule {
         IndexSearcherWrapperFactory searcherWrapperFactory = indexSearcherWrapper.get() == null
             ? (shard) -> null : indexSearcherWrapper.get();
         eventListener.beforeIndexCreated(indexSettings.getIndex(), indexSettings.getSettings());
-        final IndexStore store = getIndexStore(indexSettings, indexStoreFactories);
+        final IndexStorePlugin.DirectoryFactory directoryFactory = getDirectoryFactory(indexSettings, directoryFactories);
         final QueryCache queryCache;
         if (indexSettings.getValue(INDEX_QUERY_CACHE_ENABLED_SETTING)) {
             BiFunction<IndexSettings, IndicesQueryCache, QueryCache> queryCacheProvider = forceQueryCacheProvider.get();
@@ -399,12 +402,12 @@ public final class IndexModule {
         return new IndexService(indexSettings, indexCreationContext, environment, xContentRegistry,
                 new SimilarityService(indexSettings, scriptService, similarities),
                 shardStoreDeleter, analysisRegistry, engineFactory, circuitBreakerService, bigArrays, threadPool, scriptService,
-                client, queryCache, store, eventListener, searcherWrapperFactory, mapperRegistry,
+                client, queryCache, directoryFactory, eventListener, searcherWrapperFactory, mapperRegistry,
                 indicesFieldDataCache, searchOperationListeners, indexOperationListeners, namedWriteableRegistry);
     }
 
-    private static IndexStore getIndexStore(
+    private static IndexStorePlugin.DirectoryFactory getDirectoryFactory(
-            final IndexSettings indexSettings, final Map<String, Function<IndexSettings, IndexStore>> indexStoreFactories) {
+            final IndexSettings indexSettings, final Map<String, IndexStorePlugin.DirectoryFactory> indexStoreFactories) {
         final String storeType = indexSettings.getValue(INDEX_STORE_TYPE_SETTING);
         final Type type;
         final Boolean allowMmap = NODE_STORE_ALLOW_MMAP.get(indexSettings.getNodeSettings());
@@ -420,20 +423,16 @@ public final class IndexModule {
         if (allowMmap == false && (type == Type.MMAPFS || type == Type.HYBRIDFS)) {
             throw new IllegalArgumentException("store type [" + storeType + "] is not allowed because mmap is disabled");
         }
-        final IndexStore store;
+        final IndexStorePlugin.DirectoryFactory factory;
         if (storeType.isEmpty() || isBuiltinType(storeType)) {
-            store = new IndexStore(indexSettings);
+            factory = DEFAULT_DIRECTORY_FACTORY;
         } else {
-            Function<IndexSettings, IndexStore> factory = indexStoreFactories.get(storeType);
+            factory = indexStoreFactories.get(storeType);
             if (factory == null) {
                 throw new IllegalArgumentException("Unknown store type [" + storeType + "]");
             }
-            store = factory.apply(indexSettings);
-            if (store == null) {
-                throw new IllegalStateException("store must not be null");
         }
-        }
+        return factory;
-        return store;
     }
 
     /**

server/src/main/java/org/elasticsearch/index/IndexService.java

@@ -23,6 +23,7 @@ import org.apache.logging.log4j.message.ParameterizedMessage;
 import org.apache.lucene.index.IndexReader;
 import org.apache.lucene.search.Sort;
 import org.apache.lucene.store.AlreadyClosedException;
+import org.apache.lucene.store.Directory;
 import org.apache.lucene.util.Accountable;
 import org.elasticsearch.Assertions;
 import org.elasticsearch.Version;
@@ -65,14 +66,13 @@ import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.index.shard.ShardNotFoundException;
 import org.elasticsearch.index.shard.ShardPath;
 import org.elasticsearch.index.similarity.SimilarityService;
-import org.elasticsearch.index.store.DirectoryService;
-import org.elasticsearch.index.store.IndexStore;
 import org.elasticsearch.index.store.Store;
 import org.elasticsearch.index.translog.Translog;
 import org.elasticsearch.indices.breaker.CircuitBreakerService;
 import org.elasticsearch.indices.cluster.IndicesClusterStateService;
 import org.elasticsearch.indices.fielddata.cache.IndicesFieldDataCache;
 import org.elasticsearch.indices.mapper.MapperRegistry;
+import org.elasticsearch.plugins.IndexStorePlugin;
 import org.elasticsearch.script.ScriptService;
 import org.elasticsearch.threadpool.ThreadPool;
 
@@ -103,7 +103,7 @@ public class IndexService extends AbstractIndexComponent implements IndicesClust
     private final BitsetFilterCache bitsetFilterCache;
     private final NodeEnvironment nodeEnv;
     private final ShardStoreDeleter shardStoreDeleter;
-    private final IndexStore indexStore;
+    private final IndexStorePlugin.DirectoryFactory directoryFactory;
     private final IndexSearcherWrapper searcherWrapper;
     private final IndexCache indexCache;
     private final MapperService mapperService;
@@ -149,7 +149,7 @@ public class IndexService extends AbstractIndexComponent implements IndicesClust
             ScriptService scriptService,
             Client client,
             QueryCache queryCache,
-            IndexStore indexStore,
+            IndexStorePlugin.DirectoryFactory directoryFactory,
             IndexEventListener eventListener,
             IndexModule.IndexSearcherWrapperFactory wrapperFactory,
             MapperRegistry mapperRegistry,
@@ -200,7 +200,7 @@ public class IndexService extends AbstractIndexComponent implements IndicesClust
         this.client = client;
         this.eventListener = eventListener;
         this.nodeEnv = nodeEnv;
-        this.indexStore = indexStore;
+        this.directoryFactory = directoryFactory;
         this.engineFactory = Objects.requireNonNull(engineFactory);
         // initialize this last -- otherwise if the wrapper requires any other member to be non-null we fail with an NPE
         this.searcherWrapper = wrapperFactory.newWrapper(this);
@@ -401,9 +401,8 @@ public class IndexService extends AbstractIndexComponent implements IndicesClust
                     warmer.warm(searcher, shard, IndexService.this.indexSettings);
                 }
             };
-            // TODO we can remove either IndexStore or DirectoryService. All we need is a simple Supplier<Directory>
+            Directory directory = directoryFactory.newDirectory(this.indexSettings, path);
-            DirectoryService directoryService = indexStore.newDirectoryService(path);
+            store = new Store(shardId, this.indexSettings, directory, lock,
-            store = new Store(shardId, this.indexSettings, directoryService.newDirectory(), lock,
                     new StoreCloseListener(shardId, () -> eventListener.onStoreClosed(shardId)));
             eventListener.onStoreCreated(shardId);
             indexShard = new IndexShard(
@@ -753,8 +752,8 @@ public class IndexService extends AbstractIndexComponent implements IndicesClust
         return searcherWrapper;
     } // pkg private for testing
 
-    final IndexStore getIndexStore() {
+    final IndexStorePlugin.DirectoryFactory getDirectoryFactory() {
-        return indexStore;
+        return directoryFactory;
     } // pkg private for testing
 
     private void maybeFSyncTranslogs() {

server/src/main/java/org/elasticsearch/index/store/FsDirectoryFactory.java

@@ -30,13 +30,13 @@ import org.apache.lucene.store.NIOFSDirectory;
 import org.apache.lucene.store.NativeFSLockFactory;
 import org.apache.lucene.store.SimpleFSDirectory;
 import org.apache.lucene.store.SimpleFSLockFactory;
-import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Setting.Property;
 import org.elasticsearch.core.internal.io.IOUtils;
 import org.elasticsearch.index.IndexModule;
 import org.elasticsearch.index.IndexSettings;
 import org.elasticsearch.index.shard.ShardPath;
+import org.elasticsearch.plugins.IndexStorePlugin;
 
 import java.io.IOException;
 import java.nio.file.Files;
@@ -44,7 +44,8 @@ import java.nio.file.Path;
 import java.util.HashSet;
 import java.util.Set;
 
-public class FsDirectoryService extends DirectoryService {
+public class FsDirectoryFactory implements IndexStorePlugin.DirectoryFactory {
+
     public static final Setting<LockFactory> INDEX_LOCK_FACTOR_SETTING = new Setting<>("index.store.fs.fs_lock", "native", (s) -> {
         switch (s) {
             case "native":
@@ -56,27 +57,20 @@ public class FsDirectoryService extends DirectoryService {
         } // can we set on both - node and index level, some nodes might be running on NFS so they might need simple rather than native
     }, Property.IndexScope, Property.NodeScope);
 
-    private final ShardPath path;
-
-    @Inject
-    public FsDirectoryService(IndexSettings indexSettings, ShardPath path) {
-        super(path.getShardId(), indexSettings);
-        this.path = path;
-    }
 
     @Override
-    public Directory newDirectory() throws IOException {
+    public Directory newDirectory(IndexSettings indexSettings, ShardPath path) throws IOException {
         final Path location = path.resolveIndex();
         final LockFactory lockFactory = indexSettings.getValue(INDEX_LOCK_FACTOR_SETTING);
         Files.createDirectories(location);
-        Directory wrapped = newFSDirectory(location, lockFactory);
+        Directory wrapped = newFSDirectory(location, lockFactory, indexSettings);
         Set<String> preLoadExtensions = new HashSet<>(
                 indexSettings.getValue(IndexModule.INDEX_STORE_PRE_LOAD_SETTING));
         wrapped = setPreload(wrapped, location, lockFactory, preLoadExtensions);
         return wrapped;
     }
 
-    protected Directory newFSDirectory(Path location, LockFactory lockFactory) throws IOException {
+    protected Directory newFSDirectory(Path location, LockFactory lockFactory, IndexSettings indexSettings) throws IOException {
         final String storeType =
                 indexSettings.getSettings().get(IndexModule.INDEX_STORE_TYPE_SETTING.getKey(), IndexModule.Type.FS.getSettingsKey());
         IndexModule.Type type;

server/src/main/java/org/elasticsearch/index/store/IndexStore.java

@@ -1,39 +0,0 @@
-/*
- * 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.index.store;
-
-import org.elasticsearch.index.AbstractIndexComponent;
-import org.elasticsearch.index.IndexSettings;
-import org.elasticsearch.index.shard.ShardPath;
-
-public class IndexStore extends AbstractIndexComponent {
-
-    public IndexStore(IndexSettings indexSettings) {
-        super(indexSettings);
-    }
-
-    /**
-     * The shard store class that should be used for each shard.
-     */
-    public DirectoryService newDirectoryService(ShardPath path) {
-        return new FsDirectoryService(indexSettings, path);
-    }
-
-}

server/src/main/java/org/elasticsearch/indices/IndicesService.java

@@ -110,13 +110,13 @@ import org.elasticsearch.index.shard.IndexShardState;
 import org.elasticsearch.index.shard.IndexingOperationListener;
 import org.elasticsearch.index.shard.IndexingStats;
 import org.elasticsearch.index.shard.ShardId;
-import org.elasticsearch.index.store.IndexStore;
 import org.elasticsearch.indices.breaker.CircuitBreakerService;
 import org.elasticsearch.indices.cluster.IndicesClusterStateService;
 import org.elasticsearch.indices.fielddata.cache.IndicesFieldDataCache;
 import org.elasticsearch.indices.mapper.MapperRegistry;
 import org.elasticsearch.indices.recovery.PeerRecoveryTargetService;
 import org.elasticsearch.indices.recovery.RecoveryState;
+import org.elasticsearch.plugins.IndexStorePlugin;
 import org.elasticsearch.plugins.PluginsService;
 import org.elasticsearch.repositories.RepositoriesService;
 import org.elasticsearch.script.ScriptService;
@@ -201,7 +201,7 @@ public class IndicesService extends AbstractLifecycleComponent
     private final IndicesQueryCache indicesQueryCache;
     private final MetaStateService metaStateService;
     private final Collection<Function<IndexSettings, Optional<EngineFactory>>> engineFactoryProviders;
-    private final Map<String, Function<IndexSettings, IndexStore>> indexStoreFactories;
+    private final Map<String, IndexStorePlugin.DirectoryFactory> directoryFactories;
     final AbstractRefCounted indicesRefCount; // pkg-private for testing
     private final CountDownLatch closeLatch = new CountDownLatch(1);
 
@@ -217,7 +217,7 @@ public class IndicesService extends AbstractLifecycleComponent
                           IndexScopedSettings indexScopedSettings, CircuitBreakerService circuitBreakerService, BigArrays bigArrays,
                           ScriptService scriptService, Client client, MetaStateService metaStateService,
                           Collection<Function<IndexSettings, Optional<EngineFactory>>> engineFactoryProviders,
-                          Map<String, Function<IndexSettings, IndexStore>> indexStoreFactories) {
+                          Map<String, IndexStorePlugin.DirectoryFactory> directoryFactories) {
         this.settings = settings;
         this.threadPool = threadPool;
         this.pluginsService = pluginsService;
@@ -252,13 +252,13 @@ public class IndicesService extends AbstractLifecycleComponent
         this.engineFactoryProviders = engineFactoryProviders;
 
         // do not allow any plugin-provided index store type to conflict with a built-in type
-        for (final String indexStoreType : indexStoreFactories.keySet()) {
+        for (final String indexStoreType : directoryFactories.keySet()) {
             if (IndexModule.isBuiltinType(indexStoreType)) {
                 throw new IllegalStateException("registered index store type [" + indexStoreType + "] conflicts with a built-in type");
             }
         }
 
-        this.indexStoreFactories = indexStoreFactories;
+        this.directoryFactories = directoryFactories;
         // doClose() is called when shutting down a node, yet there might still be ongoing requests
         // that we need to wait for before closing some resources such as the caches. In order to
         // avoid closing these resources while ongoing requests are still being processed, we use a
@@ -553,7 +553,7 @@ public class IndicesService extends AbstractLifecycleComponent
             idxSettings.getNumberOfReplicas(),
             indexCreationContext);
 
-        final IndexModule indexModule = new IndexModule(idxSettings, analysisRegistry, getEngineFactory(idxSettings), indexStoreFactories);
+        final IndexModule indexModule = new IndexModule(idxSettings, analysisRegistry, getEngineFactory(idxSettings), directoryFactories);
         for (IndexingOperationListener operationListener : indexingOperationListeners) {
             indexModule.addIndexOperationListener(operationListener);
         }
@@ -620,7 +620,7 @@ public class IndicesService extends AbstractLifecycleComponent
      */
     public synchronized MapperService createIndexMapperService(IndexMetaData indexMetaData) throws IOException {
         final IndexSettings idxSettings = new IndexSettings(indexMetaData, this.settings, indexScopedSettings);
-        final IndexModule indexModule = new IndexModule(idxSettings, analysisRegistry, getEngineFactory(idxSettings), indexStoreFactories);
+        final IndexModule indexModule = new IndexModule(idxSettings, analysisRegistry, getEngineFactory(idxSettings), directoryFactories);
         pluginsService.onIndexModule(indexModule);
         return indexModule.newIndexMapperService(xContentRegistry, mapperRegistry, scriptService);
     }

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

@@ -100,7 +100,6 @@ import org.elasticsearch.http.HttpServerTransport;
 import org.elasticsearch.index.IndexSettings;
 import org.elasticsearch.index.analysis.AnalysisRegistry;
 import org.elasticsearch.index.engine.EngineFactory;
-import org.elasticsearch.index.store.IndexStore;
 import org.elasticsearch.indices.IndicesModule;
 import org.elasticsearch.indices.IndicesService;
 import org.elasticsearch.indices.analysis.AnalysisModule;
@@ -410,10 +409,10 @@ public class Node implements Closeable {
                     .collect(Collectors.toList());
 
 
-            final Map<String, Function<IndexSettings, IndexStore>> indexStoreFactories =
+            final Map<String, IndexStorePlugin.DirectoryFactory> indexStoreFactories =
                     pluginsService.filterPlugins(IndexStorePlugin.class)
                             .stream()
-                            .map(IndexStorePlugin::getIndexStoreFactories)
+                            .map(IndexStorePlugin::getDirectoryFactories)
                             .flatMap(m -> m.entrySet().stream())
                             .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
 

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

@@ -19,24 +19,40 @@
 
 package org.elasticsearch.plugins;
 
+import org.apache.lucene.store.Directory;
 import org.elasticsearch.index.IndexSettings;
-import org.elasticsearch.index.store.IndexStore;
+import org.elasticsearch.index.shard.ShardPath;
 
+import java.io.IOException;
 import java.util.Map;
-import java.util.function.Function;
 
 /**
- * A plugin that provides alternative index store implementations.
+ * A plugin that provides alternative directory implementations.
  */
 public interface IndexStorePlugin {
 
     /**
-     * The index store factories for this plugin. When an index is created the store type setting
+     * An interface that describes how to create a new directory instance per shard.
-     * {@link org.elasticsearch.index.IndexModule#INDEX_STORE_TYPE_SETTING} on the index will be examined and either use the default or a
-     * built-in type, or looked up among all the index store factories from {@link IndexStore} plugins.
-     *
-     * @return a map from store type to an index store factory
      */
-    Map<String, Function<IndexSettings, IndexStore>> getIndexStoreFactories();
+    @FunctionalInterface
+    interface DirectoryFactory {
+        /**
+         * Creates a new directory per shard. This method is called once per shard on shard creation.
+         * @param indexSettings the shards index settings
+         * @param shardPath the path the shard is using
+         * @return a new lucene directory instance
+         * @throws IOException if an IOException occurs while opening the directory
+         */
+        Directory newDirectory(IndexSettings indexSettings, ShardPath shardPath) throws IOException;
+    }
+
+    /**
+     * The {@link DirectoryFactory} mappings for this plugin. When an index is created the store type setting
+     * {@link org.elasticsearch.index.IndexModule#INDEX_STORE_TYPE_SETTING} on the index will be examined and either use the default or a
+     * built-in type, or looked up among all the directory factories from {@link IndexStorePlugin} plugins.
+     *
+     * @return a map from store type to an directory factory
+     */
+    Map<String, DirectoryFactory> getDirectoryFactories();
 
 }

server/src/test/java/org/elasticsearch/index/IndexModuleTests.java

@@ -29,6 +29,7 @@ import org.apache.lucene.search.TermStatistics;
 import org.apache.lucene.search.Weight;
 import org.apache.lucene.search.similarities.BM25Similarity;
 import org.apache.lucene.search.similarities.Similarity;
+import org.apache.lucene.store.Directory;
 import org.apache.lucene.util.SetOnce.AlreadySetException;
 import org.elasticsearch.Version;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
@@ -60,9 +61,10 @@ import org.elasticsearch.index.shard.IndexSearcherWrapper;
 import org.elasticsearch.index.shard.IndexingOperationListener;
 import org.elasticsearch.index.shard.SearchOperationListener;
 import org.elasticsearch.index.shard.ShardId;
+import org.elasticsearch.index.shard.ShardPath;
 import org.elasticsearch.index.similarity.NonNegativeScoresSimilarity;
 import org.elasticsearch.index.similarity.SimilarityService;
-import org.elasticsearch.index.store.IndexStore;
+import org.elasticsearch.index.store.FsDirectoryFactory;
 import org.elasticsearch.indices.IndicesModule;
 import org.elasticsearch.indices.IndicesQueryCache;
 import org.elasticsearch.indices.breaker.CircuitBreakerService;
@@ -70,6 +72,7 @@ import org.elasticsearch.indices.breaker.NoneCircuitBreakerService;
 import org.elasticsearch.indices.cluster.IndicesClusterStateService.AllocatedIndices.IndexRemovalReason;
 import org.elasticsearch.indices.fielddata.cache.IndicesFieldDataCache;
 import org.elasticsearch.indices.mapper.MapperRegistry;
+import org.elasticsearch.plugins.IndexStorePlugin;
 import org.elasticsearch.script.ScriptService;
 import org.elasticsearch.search.internal.SearchContext;
 import org.elasticsearch.test.ClusterServiceUtils;
@@ -86,7 +89,6 @@ import java.util.Collections;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.function.Function;
 
 import static java.util.Collections.emptyMap;
 import static org.elasticsearch.index.IndexService.IndexCreationContext.CREATE_INDEX;
@@ -174,11 +176,12 @@ public class IndexModuleTests extends ESTestCase {
             .put(IndexModule.INDEX_STORE_TYPE_SETTING.getKey(), "foo_store")
             .build();
         final IndexSettings indexSettings = IndexSettingsModule.newIndexSettings(index, settings);
-        final Map<String, Function<IndexSettings, IndexStore>> indexStoreFactories = Collections.singletonMap("foo_store", FooStore::new);
+        final Map<String, IndexStorePlugin.DirectoryFactory> indexStoreFactories = Collections.singletonMap(
+            "foo_store", new FooFunction());
         final IndexModule module = new IndexModule(indexSettings, emptyAnalysisRegistry, new InternalEngineFactory(), indexStoreFactories);
 
         final IndexService indexService = newIndexService(module);
-        assertThat(indexService.getIndexStore(), instanceOf(FooStore.class));
+        assertThat(indexService.getDirectoryFactory(), instanceOf(FooFunction.class));
 
         indexService.close("simon says", false);
     }
@@ -444,10 +447,11 @@ public class IndexModuleTests extends ESTestCase {
         }
     }
 
-    public static final class FooStore extends IndexStore {
+    public static final class FooFunction implements IndexStorePlugin.DirectoryFactory {
 
-        public FooStore(IndexSettings indexSettings) {
+        @Override
-            super(indexSettings);
+        public Directory newDirectory(IndexSettings indexSettings, ShardPath shardPath) throws IOException {
+            return new FsDirectoryFactory().newDirectory(indexSettings, shardPath);
         }
     }
 

server/src/test/java/org/elasticsearch/index/shard/IndexShardTests.java

@@ -125,7 +125,7 @@ import org.elasticsearch.test.CorruptionUtils;
 import org.elasticsearch.test.DummyShardLock;
 import org.elasticsearch.test.FieldMaskingReader;
 import org.elasticsearch.test.VersionUtils;
-import org.elasticsearch.test.store.MockFSDirectoryService;
+import org.elasticsearch.test.store.MockFSDirectoryFactory;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.junit.Assert;
 
@@ -3827,7 +3827,7 @@ public class IndexShardTests extends IndexShardTestCase {
                 readyToCloseLatch.await();
                 shard.close("testing", false);
                 // in integration tests, this is done as a listener on IndexService.
-                MockFSDirectoryService.checkIndex(logger, shard.store(), shard.shardId);
+                MockFSDirectoryFactory.checkIndex(logger, shard.store(), shard.shardId);
             } catch (InterruptedException | IOException e) {
                 throw new AssertionError(e);
             } finally {

server/src/test/java/org/elasticsearch/index/store/FsDirectoryFactoryTests.java

@@ -19,10 +19,12 @@
 package org.elasticsearch.index.store;
 
 import org.apache.lucene.store.Directory;
+import org.apache.lucene.store.FileSwitchDirectory;
 import org.apache.lucene.store.MMapDirectory;
 import org.apache.lucene.store.NIOFSDirectory;
 import org.apache.lucene.store.NoLockFactory;
 import org.apache.lucene.store.SimpleFSDirectory;
+import org.apache.lucene.store.SleepingLockWrapper;
 import org.apache.lucene.util.Constants;
 import org.elasticsearch.Version;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
@@ -36,23 +38,59 @@ import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.test.IndexSettingsModule;
 
 import java.io.IOException;
+import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.Arrays;
 import java.util.Locale;
 
-public class IndexStoreTests extends ESTestCase {
+public class FsDirectoryFactoryTests extends ESTestCase {
+
+    public void testPreload() throws IOException {
+        doTestPreload();
+        doTestPreload("nvd", "dvd", "tim");
+        doTestPreload("*");
+    }
+
+    private void doTestPreload(String...preload) throws IOException {
+        Settings build = Settings.builder()
+                .put(IndexModule.INDEX_STORE_TYPE_SETTING.getKey(), "mmapfs")
+                .putList(IndexModule.INDEX_STORE_PRE_LOAD_SETTING.getKey(), preload)
+                .build();
+        IndexSettings settings = IndexSettingsModule.newIndexSettings("foo", build);
+        Path tempDir = createTempDir().resolve(settings.getUUID()).resolve("0");
+        Files.createDirectories(tempDir);
+        ShardPath path = new ShardPath(false, tempDir, tempDir, new ShardId(settings.getIndex(), 0));
+        FsDirectoryFactory fsDirectoryFactory = new FsDirectoryFactory();
+        Directory directory = fsDirectoryFactory.newDirectory(settings, path);
+        assertFalse(directory instanceof SleepingLockWrapper);
+        if (preload.length == 0) {
+            assertTrue(directory.toString(), directory instanceof MMapDirectory);
+            assertFalse(((MMapDirectory) directory).getPreload());
+        } else if (Arrays.asList(preload).contains("*")) {
+            assertTrue(directory.toString(), directory instanceof MMapDirectory);
+            assertTrue(((MMapDirectory) directory).getPreload());
+        } else {
+            assertTrue(directory.toString(), directory instanceof FileSwitchDirectory);
+            FileSwitchDirectory fsd = (FileSwitchDirectory) directory;
+            assertTrue(fsd.getPrimaryDir() instanceof MMapDirectory);
+            assertTrue(((MMapDirectory) fsd.getPrimaryDir()).getPreload());
+            assertTrue(fsd.getSecondaryDir() instanceof MMapDirectory);
+            assertFalse(((MMapDirectory) fsd.getSecondaryDir()).getPreload());
+        }
+    }
 
     public void testStoreDirectory() throws IOException {
         Index index = new Index("foo", "fooUUID");
         final Path tempDir = createTempDir().resolve(index.getUUID()).resolve("0");
         // default
-        doTestStoreDirectory(index, tempDir, null, IndexModule.Type.FS);
+        doTestStoreDirectory(tempDir, null, IndexModule.Type.FS);
         // explicit directory impls
         for (IndexModule.Type type : IndexModule.Type.values()) {
-            doTestStoreDirectory(index, tempDir, type.name().toLowerCase(Locale.ROOT), type);
+            doTestStoreDirectory(tempDir, type.name().toLowerCase(Locale.ROOT), type);
         }
     }
 
-    private void doTestStoreDirectory(Index index, Path tempDir, String typeSettingValue, IndexModule.Type type) throws IOException {
+    private void doTestStoreDirectory(Path tempDir, String typeSettingValue, IndexModule.Type type) throws IOException {
         Settings.Builder settingsBuilder = Settings.builder()
             .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT);
         if (typeSettingValue != null) {
@@ -60,8 +98,8 @@ public class IndexStoreTests extends ESTestCase {
         }
         Settings settings = settingsBuilder.build();
         IndexSettings indexSettings = IndexSettingsModule.newIndexSettings("foo", settings);
-        FsDirectoryService service = new FsDirectoryService(indexSettings, new ShardPath(false, tempDir, tempDir, new ShardId(index, 0)));
+        FsDirectoryFactory service = new FsDirectoryFactory();
-        try (Directory directory = service.newFSDirectory(tempDir, NoLockFactory.INSTANCE)) {
+        try (Directory directory = service.newFSDirectory(tempDir, NoLockFactory.INSTANCE, indexSettings)) {
             switch (type) {
                 case HYBRIDFS:
                     assertHybridDirectory(directory);
@@ -91,8 +129,8 @@ public class IndexStoreTests extends ESTestCase {
     }
 
     private void assertHybridDirectory(Directory directory) {
-        assertTrue(directory.toString(), directory instanceof FsDirectoryService.HybridDirectory);
+        assertTrue(directory.toString(), directory instanceof FsDirectoryFactory.HybridDirectory);
-        Directory randomAccessDirectory = ((FsDirectoryService.HybridDirectory) directory).getRandomAccessDirectory();
+        Directory randomAccessDirectory = ((FsDirectoryFactory.HybridDirectory) directory).getRandomAccessDirectory();
         assertTrue("randomAccessDirectory:  " +  randomAccessDirectory.toString(), randomAccessDirectory instanceof MMapDirectory);
     }
 }

server/src/test/java/org/elasticsearch/index/store/FsDirectoryServiceTests.java

@@ -1,73 +0,0 @@
-/*
- * 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.index.store;
-
-import org.apache.lucene.store.Directory;
-import org.apache.lucene.store.FileSwitchDirectory;
-import org.apache.lucene.store.MMapDirectory;
-import org.apache.lucene.store.SleepingLockWrapper;
-import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.index.IndexModule;
-import org.elasticsearch.index.IndexSettings;
-import org.elasticsearch.index.shard.ShardId;
-import org.elasticsearch.index.shard.ShardPath;
-import org.elasticsearch.test.ESTestCase;
-import org.elasticsearch.test.IndexSettingsModule;
-
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.util.Arrays;
-
-public class FsDirectoryServiceTests extends ESTestCase {
-
-    public void testPreload() throws IOException {
-        doTestPreload();
-        doTestPreload("nvd", "dvd", "tim");
-        doTestPreload("*");
-    }
-
-    private void doTestPreload(String...preload) throws IOException {
-        Settings build = Settings.builder()
-                .put(IndexModule.INDEX_STORE_TYPE_SETTING.getKey(), "mmapfs")
-                .putList(IndexModule.INDEX_STORE_PRE_LOAD_SETTING.getKey(), preload)
-                .build();
-        IndexSettings settings = IndexSettingsModule.newIndexSettings("foo", build);
-        Path tempDir = createTempDir().resolve(settings.getUUID()).resolve("0");
-        Files.createDirectories(tempDir);
-        ShardPath path = new ShardPath(false, tempDir, tempDir, new ShardId(settings.getIndex(), 0));
-        FsDirectoryService fsDirectoryService = new FsDirectoryService(settings, path);
-        Directory directory = fsDirectoryService.newDirectory();
-        assertFalse(directory instanceof SleepingLockWrapper);
-        if (preload.length == 0) {
-            assertTrue(directory.toString(), directory instanceof MMapDirectory);
-            assertFalse(((MMapDirectory) directory).getPreload());
-        } else if (Arrays.asList(preload).contains("*")) {
-            assertTrue(directory.toString(), directory instanceof MMapDirectory);
-            assertTrue(((MMapDirectory) directory).getPreload());
-        } else {
-            assertTrue(directory.toString(), directory instanceof FileSwitchDirectory);
-            FileSwitchDirectory fsd = (FileSwitchDirectory) directory;
-            assertTrue(fsd.getPrimaryDir() instanceof MMapDirectory);
-            assertTrue(((MMapDirectory) fsd.getPrimaryDir()).getPreload());
-            assertTrue(fsd.getSecondaryDir() instanceof MMapDirectory);
-            assertFalse(((MMapDirectory) fsd.getSecondaryDir()).getPreload());
-        }
-    }
-}

server/src/test/java/org/elasticsearch/plugins/IndexStorePluginTests.java

@@ -22,15 +22,13 @@ package org.elasticsearch.plugins;
 import org.elasticsearch.bootstrap.JavaVersion;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.IndexModule;
-import org.elasticsearch.index.IndexSettings;
+import org.elasticsearch.index.store.FsDirectoryFactory;
-import org.elasticsearch.index.store.IndexStore;
 import org.elasticsearch.node.MockNode;
 import org.elasticsearch.test.ESTestCase;
 
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.Map;
-import java.util.function.Function;
 
 import static org.elasticsearch.test.hamcrest.RegexMatcher.matches;
 import static org.hamcrest.Matchers.containsString;
@@ -41,8 +39,8 @@ public class IndexStorePluginTests extends ESTestCase {
     public static class BarStorePlugin extends Plugin implements IndexStorePlugin {
 
         @Override
-        public Map<String, Function<IndexSettings, IndexStore>> getIndexStoreFactories() {
+        public Map<String, DirectoryFactory> getDirectoryFactories() {
-            return Collections.singletonMap("store", IndexStore::new);
+            return Collections.singletonMap("store", new FsDirectoryFactory());
         }
 
     }
@@ -50,8 +48,8 @@ public class IndexStorePluginTests extends ESTestCase {
     public static class FooStorePlugin extends Plugin implements IndexStorePlugin {
 
         @Override
-        public Map<String, Function<IndexSettings, IndexStore>> getIndexStoreFactories() {
+        public Map<String, DirectoryFactory> getDirectoryFactories() {
-            return Collections.singletonMap("store", IndexStore::new);
+            return Collections.singletonMap("store", new FsDirectoryFactory());
         }
 
     }
@@ -65,8 +63,8 @@ public class IndexStorePluginTests extends ESTestCase {
         }
 
         @Override
-        public Map<String, Function<IndexSettings, IndexStore>> getIndexStoreFactories() {
+        public Map<String, DirectoryFactory> getDirectoryFactories() {
-            return Collections.singletonMap(TYPE, IndexStore::new);
+            return Collections.singletonMap(TYPE, new FsDirectoryFactory());
         }
 
     }
@@ -86,11 +84,11 @@ public class IndexStorePluginTests extends ESTestCase {
         if (JavaVersion.current().compareTo(JavaVersion.parse("9")) >= 0) {
             assertThat(e, hasToString(matches(
                     "java.lang.IllegalStateException: Duplicate key store \\(attempted merging values " +
-                            "org.elasticsearch.plugins.IndexStorePluginTests\\$BarStorePlugin.* " +
+                            "org.elasticsearch.index.store.FsDirectoryFactory@[\\w\\d]+ " +
-                            "and org.elasticsearch.plugins.IndexStorePluginTests\\$FooStorePlugin.*\\)")));
+                            "and org.elasticsearch.index.store.FsDirectoryFactory@[\\w\\d]+\\)")));
         } else {
             assertThat(e, hasToString(matches(
-                    "java.lang.IllegalStateException: Duplicate key org.elasticsearch.plugins.IndexStorePluginTests\\$BarStorePlugin.*")));
+                    "java.lang.IllegalStateException: Duplicate key org.elasticsearch.index.store.FsDirectoryFactory@[\\w\\d]+")));
         }
     }
 

server/src/test/java/org/elasticsearch/search/basic/SearchWithRandomIOExceptionsIT.java

@@ -37,7 +37,7 @@ import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.search.sort.SortOrder;
 import org.elasticsearch.test.ESIntegTestCase;
-import org.elasticsearch.test.store.MockFSDirectoryService;
+import org.elasticsearch.test.store.MockFSDirectoryFactory;
 import org.elasticsearch.test.store.MockFSIndexStore;
 import java.io.IOException;
 import java.util.Arrays;
@@ -104,16 +104,16 @@ public class SearchWithRandomIOExceptionsIT extends ESIntegTestCase {
             client().admin().indices().prepareFlush("test").execute().get();
             client().admin().indices().prepareClose("test").execute().get();
             client().admin().indices().prepareUpdateSettings("test").setSettings(Settings.builder()
-                .put(MockFSDirectoryService.RANDOM_IO_EXCEPTION_RATE_SETTING.getKey(), exceptionRate)
+                .put(MockFSDirectoryFactory.RANDOM_IO_EXCEPTION_RATE_SETTING.getKey(), exceptionRate)
-                .put(MockFSDirectoryService.RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING.getKey(), exceptionOnOpenRate));
+                .put(MockFSDirectoryFactory.RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING.getKey(), exceptionOnOpenRate));
             client().admin().indices().prepareOpen("test").execute().get();
         } else {
             Settings.Builder settings = Settings.builder()
                 .put("index.number_of_replicas", randomIntBetween(0, 1))
                 .put(MockFSIndexStore.INDEX_CHECK_INDEX_ON_CLOSE_SETTING.getKey(), false)
-                .put(MockFSDirectoryService.RANDOM_IO_EXCEPTION_RATE_SETTING.getKey(), exceptionRate)
+                .put(MockFSDirectoryFactory.RANDOM_IO_EXCEPTION_RATE_SETTING.getKey(), exceptionRate)
                 // we cannot expect that the index will be valid
-                .put(MockFSDirectoryService.RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING.getKey(), exceptionOnOpenRate);
+                .put(MockFSDirectoryFactory.RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING.getKey(), exceptionOnOpenRate);
             logger.info("creating index: [test] using settings: [{}]", settings.build());
             client().admin().indices().prepareCreate("test")
                 .setSettings(settings)
@@ -195,8 +195,8 @@ public class SearchWithRandomIOExceptionsIT extends ESIntegTestCase {
             // check the index still contains the records that we indexed without errors
             client().admin().indices().prepareClose("test").execute().get();
             client().admin().indices().prepareUpdateSettings("test").setSettings(Settings.builder()
-                .put(MockFSDirectoryService.RANDOM_IO_EXCEPTION_RATE_SETTING.getKey(), 0)
+                .put(MockFSDirectoryFactory.RANDOM_IO_EXCEPTION_RATE_SETTING.getKey(), 0)
-                .put(MockFSDirectoryService.RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING.getKey(), 0));
+                .put(MockFSDirectoryFactory.RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING.getKey(), 0));
             client().admin().indices().prepareOpen("test").execute().get();
             ensureGreen();
             SearchResponse searchResponse = client().prepareSearch().setTypes("type")

test/framework/src/main/java/org/elasticsearch/test/store/MockFSDirectoryFactory.java

@@ -19,19 +19,16 @@
 
 package org.elasticsearch.test.store;
 
-import com.carrotsearch.randomizedtesting.SeedUtils;
 import com.carrotsearch.randomizedtesting.generators.RandomPicks;
 import org.apache.logging.log4j.Logger;
 import org.apache.lucene.index.CheckIndex;
 import org.apache.lucene.store.BaseDirectoryWrapper;
 import org.apache.lucene.store.Directory;
-import org.apache.lucene.store.LockFactory;
 import org.apache.lucene.store.LockObtainFailedException;
 import org.apache.lucene.store.MockDirectoryWrapper;
 import org.apache.lucene.util.LuceneTestCase;
 import org.apache.lucene.util.TestRuleMarkFailure;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
-import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.io.stream.BytesStreamOutput;
 import org.elasticsearch.common.lucene.Lucene;
 import org.elasticsearch.common.settings.Setting;
@@ -41,8 +38,9 @@ import org.elasticsearch.index.IndexModule;
 import org.elasticsearch.index.IndexSettings;
 import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.index.shard.ShardPath;
-import org.elasticsearch.index.store.FsDirectoryService;
+import org.elasticsearch.index.store.FsDirectoryFactory;
 import org.elasticsearch.index.store.Store;
+import org.elasticsearch.plugins.IndexStorePlugin;
 import org.elasticsearch.test.ESIntegTestCase;
 import org.elasticsearch.test.ESTestCase;
 import org.junit.Assert;
@@ -51,12 +49,11 @@ import java.io.Closeable;
 import java.io.IOException;
 import java.io.PrintStream;
 import java.nio.charset.StandardCharsets;
-import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.Random;
 import java.util.Set;
 
-public class MockFSDirectoryService extends FsDirectoryService {
+public class MockFSDirectoryFactory implements IndexStorePlugin.DirectoryFactory {
 
     public static final Setting<Double> RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING =
         Setting.doubleSetting("index.store.mock.random.io_exception_rate_on_open", 0.0d,  0.0d, Property.IndexScope, Property.NodeScope);
@@ -65,42 +62,12 @@ public class MockFSDirectoryService extends FsDirectoryService {
     public static final Setting<Boolean> CRASH_INDEX_SETTING =
         Setting.boolSetting("index.store.mock.random.crash_index", true, Property.IndexScope, Property.NodeScope);
 
-    private final FsDirectoryService delegateService;
+    @Override
-    private final Random random;
+    public Directory newDirectory(IndexSettings idxSettings, ShardPath path) throws IOException {
-    private final double randomIOExceptionRate;
-    private final double randomIOExceptionRateOnOpen;
-    private final MockDirectoryWrapper.Throttling throttle;
-    private final boolean crashIndex;
-
-    @Inject
-    public MockFSDirectoryService(IndexSettings idxSettings, final ShardPath path) {
-        super(idxSettings, path);
         Settings indexSettings = idxSettings.getSettings();
-        final long seed = idxSettings.getValue(ESIntegTestCase.INDEX_TEST_SEED_SETTING);
+        Random random = new Random(idxSettings.getValue(ESIntegTestCase.INDEX_TEST_SEED_SETTING));
-        this.random = new Random(seed);
+        return wrap(randomDirectoryService(random, idxSettings, path), random, indexSettings,
-
+            path.getShardId());
-        randomIOExceptionRate = RANDOM_IO_EXCEPTION_RATE_SETTING.get(indexSettings);
-        randomIOExceptionRateOnOpen = RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING.get(indexSettings);
-        random.nextInt(shardId.getId() + 1); // some randomness per shard
-        throttle = MockDirectoryWrapper.Throttling.NEVER;
-        crashIndex = CRASH_INDEX_SETTING.get(indexSettings);
-
-        if (logger.isDebugEnabled()) {
-            logger.debug("Using MockDirWrapper with seed [{}] throttle: [{}] crashIndex: [{}]", SeedUtils.formatSeed(seed),
-                    throttle, crashIndex);
-        }
-        delegateService = randomDirectoryService(idxSettings, path);
-    }
-
-
-    @Override
-    public Directory newDirectory() throws IOException {
-        return wrap(delegateService.newDirectory());
-    }
-
-    @Override
-    protected synchronized Directory newFSDirectory(Path location, LockFactory lockFactory) throws IOException {
-        throw new UnsupportedOperationException();
     }
 
     public static void checkIndex(Logger logger, Store store, ShardId shardId) {
@@ -138,8 +105,14 @@ public class MockFSDirectoryService extends FsDirectoryService {
         }
     }
 
-    private Directory wrap(Directory dir) {
+    private Directory wrap(Directory dir, Random random, Settings indexSettings, ShardId shardId) {
-        final ElasticsearchMockDirectoryWrapper w = new ElasticsearchMockDirectoryWrapper(random, dir, this.crashIndex);
+
+        double randomIOExceptionRate = RANDOM_IO_EXCEPTION_RATE_SETTING.get(indexSettings);
+        double randomIOExceptionRateOnOpen = RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING.get(indexSettings);
+        random.nextInt(shardId.getId() + 1); // some randomness per shard
+        MockDirectoryWrapper.Throttling throttle = MockDirectoryWrapper.Throttling.NEVER;
+        boolean crashIndex = CRASH_INDEX_SETTING.get(indexSettings);
+        final ElasticsearchMockDirectoryWrapper w = new ElasticsearchMockDirectoryWrapper(random, dir, crashIndex);
         w.setRandomIOExceptionRate(randomIOExceptionRate);
         w.setRandomIOExceptionRateOnOpen(randomIOExceptionRateOnOpen);
         w.setThrottling(throttle);
@@ -151,7 +124,7 @@ public class MockFSDirectoryService extends FsDirectoryService {
         return w;
     }
 
-    private FsDirectoryService randomDirectoryService(IndexSettings indexSettings, ShardPath path) {
+    private Directory randomDirectoryService(Random random, IndexSettings indexSettings, ShardPath path) throws IOException {
         final IndexMetaData build = IndexMetaData.builder(indexSettings.getIndexMetaData())
             .settings(Settings.builder()
                 // don't use the settings from indexSettings#getSettings() they are merged with node settings and might contain
@@ -161,7 +134,7 @@ public class MockFSDirectoryService extends FsDirectoryService {
                     RandomPicks.randomFrom(random, IndexModule.Type.values()).getSettingsKey()))
             .build();
         final IndexSettings newIndexSettings = new IndexSettings(build, indexSettings.getNodeSettings());
-        return new FsDirectoryService(newIndexSettings, path);
+        return new FsDirectoryFactory().newDirectory(newIndexSettings, path);
     }
 
     public static final class ElasticsearchMockDirectoryWrapper extends MockDirectoryWrapper {

test/framework/src/main/java/org/elasticsearch/test/store/MockFSIndexStore.java

@@ -26,14 +26,10 @@ import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Setting.Property;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.IndexModule;
-import org.elasticsearch.index.IndexSettings;
 import org.elasticsearch.index.shard.IndexEventListener;
 import org.elasticsearch.index.shard.IndexShard;
 import org.elasticsearch.index.shard.IndexShardState;
 import org.elasticsearch.index.shard.ShardId;
-import org.elasticsearch.index.shard.ShardPath;
-import org.elasticsearch.index.store.DirectoryService;
-import org.elasticsearch.index.store.IndexStore;
 import org.elasticsearch.plugins.IndexStorePlugin;
 import org.elasticsearch.plugins.Plugin;
 
@@ -43,9 +39,8 @@ import java.util.EnumSet;
 import java.util.IdentityHashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.function.Function;
 
-public class MockFSIndexStore extends IndexStore {
+public final class MockFSIndexStore {
 
     public static final Setting<Boolean> INDEX_CHECK_INDEX_ON_CLOSE_SETTING =
         Setting.boolSetting("index.store.mock.check_index_on_close", true, Property.IndexScope, Property.NodeScope);
@@ -59,14 +54,14 @@ public class MockFSIndexStore extends IndexStore {
         @Override
         public List<Setting<?>> getSettings() {
             return Arrays.asList(INDEX_CHECK_INDEX_ON_CLOSE_SETTING,
-            MockFSDirectoryService.CRASH_INDEX_SETTING,
+            MockFSDirectoryFactory.CRASH_INDEX_SETTING,
-            MockFSDirectoryService.RANDOM_IO_EXCEPTION_RATE_SETTING,
+            MockFSDirectoryFactory.RANDOM_IO_EXCEPTION_RATE_SETTING,
-            MockFSDirectoryService.RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING);
+            MockFSDirectoryFactory.RANDOM_IO_EXCEPTION_RATE_ON_OPEN_SETTING);
         }
 
         @Override
-        public Map<String, Function<IndexSettings, IndexStore>> getIndexStoreFactories() {
+        public Map<String, DirectoryFactory> getDirectoryFactories() {
-            return Collections.singletonMap("mock", MockFSIndexStore::new);
+            return Collections.singletonMap("mock", new MockFSDirectoryFactory());
         }
 
         @Override
@@ -80,15 +75,6 @@ public class MockFSIndexStore extends IndexStore {
         }
     }
 
-    MockFSIndexStore(IndexSettings indexSettings) {
-        super(indexSettings);
-    }
-
-    @Override
-    public DirectoryService newDirectoryService(ShardPath path) {
-        return new MockFSDirectoryService(indexSettings, path);
-    }
-
     private static final EnumSet<IndexShardState> validCheckIndexStates = EnumSet.of(
             IndexShardState.STARTED, IndexShardState.POST_RECOVERY
     );
@@ -101,7 +87,7 @@ public class MockFSIndexStore extends IndexStore {
                 Boolean remove = shardSet.remove(indexShard);
                 if (remove == Boolean.TRUE) {
                     Logger logger = Loggers.getLogger(getClass(), indexShard.shardId());
-                    MockFSDirectoryService.checkIndex(logger, indexShard.store(), indexShard.shardId());
+                    MockFSDirectoryFactory.checkIndex(logger, indexShard.store(), indexShard.shardId());
                 }
             }
         }
@@ -115,5 +101,4 @@ public class MockFSIndexStore extends IndexStore {
 
         }
     }
-
 }