Remove the node local storage setting (#54381)

In 7.8.0 the node.local_storage setting was deprecated in favor of
requiring all nodes to have a form of persistent storage. This commit
removes the node.local_storage setting.

docs/reference/migration/migrate_8_0/settings.asciidoc

@@ -46,7 +46,8 @@ favor of setting `node.remote_cluster_client`. In Elasticsearch 8.0.0, the
 setting `cluster.remote.connect` is removed.
 
 [float]
-==== `node.local_storage` is deprecated
+==== `node.local_storage` is removed
 
 In Elasticsearch 7.8.0, the setting `node.local_storage` was deprecated and
-beginning in Elasticsearch 8.0.0 all nodes will require local storage.
+beginning in Elasticsearch 8.0.0 all nodes will require local storage. Therefore,
+the `node.local_storage` setting has been removed.

server/src/main/java/org/elasticsearch/cluster/node/DiscoveryNode.java

@@ -51,18 +51,6 @@ public class DiscoveryNode implements Writeable, ToXContentFragment {
 
     static final String COORDINATING_ONLY = "coordinating_only";
 
-    public static boolean nodeRequiresLocalStorage(Settings settings) {
-        boolean localStorageEnable = Node.NODE_LOCAL_STORAGE_SETTING.get(settings);
-        if (localStorageEnable == false &&
-            (Node.NODE_DATA_SETTING.get(settings) ||
-                Node.NODE_MASTER_SETTING.get(settings))
-            ) {
-            // TODO: make this a proper setting validation logic, requiring multi-settings validation
-            throw new IllegalArgumentException("storage can not be disabled for master and data nodes");
-        }
-        return localStorageEnable;
-    }
-
     public static boolean isMasterNode(Settings settings) {
         return Node.NODE_MASTER_SETTING.get(settings);
     }

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

@@ -403,7 +403,6 @@ public final class ClusterSettings extends AbstractScopedSettings {
             Node.NODE_INGEST_SETTING,
             Node.NODE_REMOTE_CLUSTER_CLIENT,
             Node.NODE_ATTRIBUTES,
-            Node.NODE_LOCAL_STORAGE_SETTING,
             AutoCreateIndex.AUTO_CREATE_INDEX_SETTING,
             BaseRestHandler.MULTI_ALLOW_EXPLICIT_INDEX,
             ClusterName.CLUSTER_NAME_SETTING,

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

@@ -90,15 +90,11 @@ public class Environment {
     private final Path tmpFile;
 
     public Environment(final Settings settings, final Path configPath) {
-        this(settings, configPath, true);
-    }
-
-    public Environment(final Settings settings, final Path configPath, final boolean nodeLocalStorage) {
-        this(settings, configPath, nodeLocalStorage, PathUtils.get(System.getProperty("java.io.tmpdir")));
+        this(settings, configPath, PathUtils.get(System.getProperty("java.io.tmpdir")));
     }
 
     // Should only be called directly by this class's unit tests
-    Environment(final Settings settings, final Path configPath, final boolean nodeLocalStorage, final Path tmpPath) {
+    Environment(final Settings settings, final Path configPath, final Path tmpPath) {
         final Path homeFile;
         if (PATH_HOME_SETTING.exists(settings)) {
             homeFile = PathUtils.get(PATH_HOME_SETTING.get(settings)).toAbsolutePath().normalize();
@@ -118,22 +114,13 @@ public class Environment {
 
         List<String> dataPaths = PATH_DATA_SETTING.get(settings);
         final ClusterName clusterName = ClusterName.CLUSTER_NAME_SETTING.get(settings);
-        if (nodeLocalStorage) {
-            if (dataPaths.isEmpty() == false) {
-                dataFiles = new Path[dataPaths.size()];
-                for (int i = 0; i < dataPaths.size(); i++) {
-                    dataFiles[i] = PathUtils.get(dataPaths.get(i)).toAbsolutePath().normalize();
-                }
-            } else {
-                dataFiles = new Path[]{homeFile.resolve("data")};
+        if (dataPaths.isEmpty() == false) {
+            dataFiles = new Path[dataPaths.size()];
+            for (int i = 0; i < dataPaths.size(); i++) {
+                dataFiles[i] = PathUtils.get(dataPaths.get(i)).toAbsolutePath().normalize();
             }
         } else {
-            if (dataPaths.isEmpty()) {
-                dataFiles = EMPTY_PATH_ARRAY;
-            } else {
-                final String paths = String.join(",", dataPaths);
-                throw new IllegalStateException("node does not require local storage yet path.data is set to [" + paths + "]");
-            }
+            dataFiles = new Path[]{homeFile.resolve("data")};
         }
         if (PATH_SHARED_DATA_SETTING.exists(settings)) {
             sharedDataFile = PathUtils.get(PATH_SHARED_DATA_SETTING.get(settings)).toAbsolutePath().normalize();

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

@@ -247,13 +247,6 @@ public final class NodeEnvironment  implements Closeable {
      * @param settings settings from elasticsearch.yml
      */
     public NodeEnvironment(Settings settings, Environment environment) throws IOException {
-        if (!DiscoveryNode.nodeRequiresLocalStorage(settings)) {
-            nodePaths = null;
-            sharedDataPath = null;
-            locks = null;
-            nodeMetaData = new NodeMetaData(generateNodeId(settings), Version.CURRENT);
-            return;
-        }
         boolean success = false;
 
         try {

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

@@ -1029,8 +1029,7 @@ public class IndicesService extends AbstractLifecycleComponent
     public enum ShardDeletionCheckResult {
         FOLDER_FOUND_CAN_DELETE, // shard data exists and can be deleted
         STILL_ALLOCATED, // the shard is still allocated / active on this node
-        NO_FOLDER_FOUND, // the shards data locations do not exist
-        NO_LOCAL_STORAGE // node does not have local storage (see DiscoveryNode.nodeRequiresLocalStorage)
+        NO_FOLDER_FOUND // the shards data locations do not exist
     }
 
     /**
@@ -1042,25 +1041,21 @@ public class IndicesService extends AbstractLifecycleComponent
     public ShardDeletionCheckResult canDeleteShardContent(ShardId shardId, IndexSettings indexSettings) {
         assert shardId.getIndex().equals(indexSettings.getIndex());
         final IndexService indexService = indexService(shardId.getIndex());
-        if (nodeEnv.hasNodeFile()) {
-            final boolean isAllocated = indexService != null && indexService.hasShard(shardId.id());
-            if (isAllocated) {
-                return ShardDeletionCheckResult.STILL_ALLOCATED; // we are allocated - can't delete the shard
-            } else if (indexSettings.hasCustomDataPath()) {
-                // lets see if it's on a custom path (return false if the shared doesn't exist)
-                // we don't need to delete anything that is not there
-                return Files.exists(nodeEnv.resolveCustomLocation(indexSettings.customDataPath(), shardId)) ?
-                        ShardDeletionCheckResult.FOLDER_FOUND_CAN_DELETE :
-                        ShardDeletionCheckResult.NO_FOLDER_FOUND;
-            } else {
-                // lets see if it's path is available (return false if the shared doesn't exist)
-                // we don't need to delete anything that is not there
-                return FileSystemUtils.exists(nodeEnv.availableShardPaths(shardId)) ?
-                        ShardDeletionCheckResult.FOLDER_FOUND_CAN_DELETE :
-                        ShardDeletionCheckResult.NO_FOLDER_FOUND;
-            }
+        final boolean isAllocated = indexService != null && indexService.hasShard(shardId.id());
+        if (isAllocated) {
+            return ShardDeletionCheckResult.STILL_ALLOCATED; // we are allocated - can't delete the shard
+        } else if (indexSettings.hasCustomDataPath()) {
+            // lets see if it's on a custom path (return false if the shared doesn't exist)
+            // we don't need to delete anything that is not there
+            return Files.exists(nodeEnv.resolveCustomLocation(indexSettings.customDataPath(), shardId)) ?
+                ShardDeletionCheckResult.FOLDER_FOUND_CAN_DELETE :
+                ShardDeletionCheckResult.NO_FOLDER_FOUND;
         } else {
-            return ShardDeletionCheckResult.NO_LOCAL_STORAGE;
+            // lets see if it's path is available (return false if the shared doesn't exist)
+            // we don't need to delete anything that is not there
+            return FileSystemUtils.exists(nodeEnv.availableShardPaths(shardId)) ?
+                ShardDeletionCheckResult.FOLDER_FOUND_CAN_DELETE :
+                ShardDeletionCheckResult.NO_FOLDER_FOUND;
         }
     }
 

server/src/main/java/org/elasticsearch/indices/store/IndicesStore.java

@@ -166,10 +166,6 @@ public class IndicesStore implements ClusterStateListener, Closeable {
                         case NO_FOLDER_FOUND:
                             folderNotFoundCache.add(shardId);
                             break;
-                        case NO_LOCAL_STORAGE:
-                            assert false : "shard deletion only runs on data nodes which always have local storage";
-                            // nothing to do
-                            break;
                         case STILL_ALLOCATED:
                             // nothing to do
                             break;

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

@@ -203,15 +203,6 @@ public class Node implements Closeable {
     public static final Setting<Boolean> NODE_REMOTE_CLUSTER_CLIENT =
         Setting.boolSetting("node.remote_cluster_client", true, Property.NodeScope);
 
-    /**
-    * controls whether the node is allowed to persist things like metadata to disk
-    * Note that this does not control whether the node stores actual indices (see
-    * {@link #NODE_DATA_SETTING}). However, if this is false, {@link #NODE_DATA_SETTING}
-    * and {@link #NODE_MASTER_SETTING} must also be false.
-    *
-    */
-    public static final Setting<Boolean> NODE_LOCAL_STORAGE_SETTING =
-        Setting.boolSetting("node.local_storage", true, Property.Deprecated, Property.NodeScope);
     public static final Setting<String> NODE_NAME_SETTING = Setting.simpleString("node.name", Property.NodeScope);
     public static final Setting.AffixSetting<String> NODE_ATTRIBUTES = Setting.prefixKeySetting("node.attr.", (key) ->
         new Setting<>(key, "", (value) -> {
@@ -333,7 +324,7 @@ public class Node implements Closeable {
 
             // create the environment based on the finalized (processed) view of the settings
             // this is just to makes sure that people get the same settings, no matter where they ask them from
-            this.environment = new Environment(settings, initialEnvironment.configFile(), Node.NODE_LOCAL_STORAGE_SETTING.get(settings));
+            this.environment = new Environment(settings, initialEnvironment.configFile());
             Environment.assertEquivalent(initialEnvironment, this.environment);
 
             final List<ExecutorBuilder<?>> executorBuilders = pluginsService.getExecutorBuilders(settings);

server/src/test/java/org/elasticsearch/env/EnvironmentTests.java

@@ -32,11 +32,8 @@ import static org.hamcrest.CoreMatchers.endsWith;
 import static org.hamcrest.CoreMatchers.notNullValue;
 import static org.hamcrest.CoreMatchers.nullValue;
 import static org.hamcrest.CoreMatchers.startsWith;
-import static org.hamcrest.Matchers.arrayWithSize;
-import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.hasSize;
-import static org.hamcrest.Matchers.hasToString;
 
 /**
  * Simple unit-tests for Environment.java
@@ -124,37 +121,11 @@ public class EnvironmentTests extends ESTestCase {
         assertThat(environment.configFile(), equalTo(pathHome.resolve("config")));
     }
 
-    public void testNodeDoesNotRequireLocalStorage() {
-        final Path pathHome = createTempDir().toAbsolutePath();
-        final Settings settings =
-                Settings.builder()
-                        .put("path.home", pathHome)
-                        .put("node.master", false)
-                        .put("node.data", false)
-                        .build();
-        final Environment environment = new Environment(settings, null, false);
-        assertThat(environment.dataFiles(), arrayWithSize(0));
-    }
-
-    public void testNodeDoesNotRequireLocalStorageButHasPathData() {
-        final Path pathHome = createTempDir().toAbsolutePath();
-        final Path pathData = pathHome.resolve("data");
-        final Settings settings =
-                Settings.builder()
-                        .put("path.home", pathHome)
-                        .put("path.data", pathData)
-                        .put("node.master", false)
-                        .put("node.data", false)
-                        .build();
-        final IllegalStateException e = expectThrows(IllegalStateException.class, () -> new Environment(settings, null, false));
-        assertThat(e, hasToString(containsString("node does not require local storage yet path.data is set to [" + pathData + "]")));
-    }
-
     public void testNonExistentTempPathValidation() {
         Settings build = Settings.builder()
             .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
             .build();
-        Environment environment = new Environment(build, null, true, createTempDir().resolve("this_does_not_exist"));
+        Environment environment = new Environment(build, null, createTempDir().resolve("this_does_not_exist"));
         FileNotFoundException e = expectThrows(FileNotFoundException.class, environment::validateTmpFile);
         assertThat(e.getMessage(), startsWith("Temporary file directory ["));
         assertThat(e.getMessage(), endsWith("this_does_not_exist] does not exist or is not accessible"));
@@ -164,7 +135,7 @@ public class EnvironmentTests extends ESTestCase {
         Settings build = Settings.builder()
             .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
             .build();
-        Environment environment = new Environment(build, null, true, createTempFile("something", ".test"));
+        Environment environment = new Environment(build, null, createTempFile("something", ".test"));
         IOException e = expectThrows(IOException.class, environment::validateTmpFile);
         assertThat(e.getMessage(), startsWith("Configured temporary file directory ["));
         assertThat(e.getMessage(), endsWith(".test] is not a directory"));
@@ -184,7 +155,7 @@ public class EnvironmentTests extends ESTestCase {
         // the above paths will be treated as relative to the working directory
         final Path workingDirectory = PathUtils.get(System.getProperty("user.dir"));
 
-        final Environment environment = new Environment(settings, null, true, createTempDir());
+        final Environment environment = new Environment(settings, null, createTempDir());
         final String homePath = Environment.PATH_HOME_SETTING.get(environment.settings());
         assertPath(homePath, workingDirectory.resolve("home"));
 

server/src/test/java/org/elasticsearch/env/NodeEnvironmentTests.java

@@ -22,7 +22,6 @@ import org.apache.lucene.index.SegmentInfos;
 import org.apache.lucene.util.LuceneTestCase;
 import org.elasticsearch.common.SuppressForbidden;
 import org.elasticsearch.common.io.PathUtils;
-import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.util.concurrent.AbstractRunnable;
 import org.elasticsearch.common.util.set.Sets;
@@ -52,7 +51,6 @@ import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.Matchers.arrayWithSize;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.empty;
-import static org.hamcrest.Matchers.not;
 import static org.hamcrest.Matchers.startsWith;
 
 @LuceneTestCase.SuppressFileSystems("ExtrasFS") // TODO: fix test to allow extras
@@ -385,28 +383,6 @@ public class NodeEnvironmentTests extends ESTestCase {
         env.close();
     }
 
-    public void testNodeIdNotPersistedAtInitialization() throws IOException {
-        NodeEnvironment env = newNodeEnvironment(new String[0], Settings.builder()
-            .put("node.local_storage", false)
-            .put("node.master", false)
-            .put("node.data", false)
-            .build());
-        String nodeID = env.nodeId();
-        env.close();
-        final String[] paths = tmpPaths();
-        env = newNodeEnvironment(paths, Settings.EMPTY);
-        assertThat("previous node didn't have local storage enabled, id should change", env.nodeId(), not(equalTo(nodeID)));
-        nodeID = env.nodeId();
-        env.close();
-        env = newNodeEnvironment(paths, Settings.EMPTY);
-        assertThat(env.nodeId(), not(equalTo(nodeID)));
-        env.close();
-        env = newNodeEnvironment(Settings.EMPTY);
-        assertThat(env.nodeId(), not(equalTo(nodeID)));
-        env.close();
-        assertSettingDeprecationsAndWarnings(new Setting<?>[]{Node.NODE_LOCAL_STORAGE_SETTING});
-    }
-
     public void testExistingTempFiles() throws IOException {
         String[] paths = tmpPaths();
         // simulate some previous left over temp files