Always enforce default tier preference (ENFORCE_DEFAULT_TIER_PREFEREN…

…CE is ignored) (#79751)

server/src/main/java/org/elasticsearch/cluster/metadata/MetadataCreateIndexService.java

@@ -129,8 +129,6 @@ public class MetadataCreateIndexService {
     private final boolean forbidPrivateIndexSettings;
     private final Set<IndexSettingProvider> indexSettingProviders = new HashSet<>();
 
-    private volatile boolean enforceDefaultTierPreference;
-
     public MetadataCreateIndexService(
         final Settings settings,
         final ClusterService clusterService,
@@ -156,14 +154,6 @@ public MetadataCreateIndexService(
         this.systemIndices = systemIndices;
         this.forbidPrivateIndexSettings = forbidPrivateIndexSettings;
         this.shardLimitValidator = shardLimitValidator;
-
-        enforceDefaultTierPreference = DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING.get(settings);
-        clusterService.getClusterSettings().addSettingsUpdateConsumer(DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING,
-            this::setEnforceDefaultTierPreference);
-    }
-
-    public void setEnforceDefaultTierPreference(boolean enforceDefaultTierPreference) {
-        this.enforceDefaultTierPreference = enforceDefaultTierPreference;
     }
 
     /**
@@ -492,8 +482,7 @@ private ClusterState applyCreateIndexRequestWithV1Templates(final ClusterState c
 
         final Settings aggregatedIndexSettings =
             aggregateIndexSettings(currentState, request, resolveSettings(templates),
-                null, settings, indexScopedSettings, shardLimitValidator, indexSettingProviders,
-                this.enforceDefaultTierPreference);
+                null, settings, indexScopedSettings, shardLimitValidator, indexSettingProviders);
         int routingNumShards = getIndexNumberOfRoutingShards(aggregatedIndexSettings, null);
         IndexMetadata tmpImd = buildAndValidateTemporaryIndexMetadata(aggregatedIndexSettings, request, routingNumShards);
 
@@ -528,8 +517,7 @@ private ClusterState applyCreateIndexRequestWithV2Template(final ClusterState cu
         final Settings aggregatedIndexSettings =
             aggregateIndexSettings(currentState, request,
                 resolveSettings(currentState.metadata(), templateName),
-                null, settings, indexScopedSettings, shardLimitValidator, indexSettingProviders,
-                this.enforceDefaultTierPreference);
+                null, settings, indexScopedSettings, shardLimitValidator, indexSettingProviders);
         int routingNumShards = getIndexNumberOfRoutingShards(aggregatedIndexSettings, null);
         IndexMetadata tmpImd = buildAndValidateTemporaryIndexMetadata(aggregatedIndexSettings, request, routingNumShards);
 
@@ -583,8 +571,7 @@ private ClusterState applyCreateIndexRequestForSystemDataStream(final ClusterSta
             settings,
             indexScopedSettings,
             shardLimitValidator,
-            indexSettingProviders,
-            this.enforceDefaultTierPreference
+            indexSettingProviders
         );
         final int routingNumShards = getIndexNumberOfRoutingShards(aggregatedIndexSettings, null);
         final IndexMetadata tmpImd = buildAndValidateTemporaryIndexMetadata(aggregatedIndexSettings, request, routingNumShards);
@@ -648,7 +635,7 @@ private ClusterState applyCreateIndexRequestWithExistingMetadata(final ClusterSt
         }
 
         final Settings aggregatedIndexSettings = aggregateIndexSettings(currentState, request, Settings.EMPTY,
-            sourceMetadata, settings, indexScopedSettings, shardLimitValidator, indexSettingProviders, this.enforceDefaultTierPreference);
+            sourceMetadata, settings, indexScopedSettings, shardLimitValidator, indexSettingProviders);
         final int routingNumShards = getIndexNumberOfRoutingShards(aggregatedIndexSettings, sourceMetadata);
         IndexMetadata tmpImd = buildAndValidateTemporaryIndexMetadata(aggregatedIndexSettings, request, routingNumShards);
 
@@ -710,7 +697,7 @@ static Map<String, Object> parseV1Mappings(String mappingsJson, List<CompressedX
     static Settings aggregateIndexSettings(ClusterState currentState, CreateIndexClusterStateUpdateRequest request,
                                            Settings combinedTemplateSettings, @Nullable IndexMetadata sourceMetadata, Settings settings,
                                            IndexScopedSettings indexScopedSettings, ShardLimitValidator shardLimitValidator,
-                                           Set<IndexSettingProvider> indexSettingProviders, boolean enforceDefaultTierPreference) {
+                                           Set<IndexSettingProvider> indexSettingProviders) {
         final boolean isDataStreamIndex = request.dataStreamName() != null;
 
         // Create builders for the template and request settings. We transform these into builders
@@ -770,16 +757,14 @@ static Settings aggregateIndexSettings(ClusterState currentState, CreateIndexClu
         indexSettingsBuilder.put(requestSettings.build());
 
         if (sourceMetadata == null) { // not for shrink/split/clone
-            if (enforceDefaultTierPreference) {
-                // regardless of any previous logic, we're going to force there
-                // to be an appropriate non-empty value for the tier preference
-                String currentTierPreference = indexSettingsBuilder.get(DataTier.TIER_PREFERENCE);
-                if (DataTier.parseTierList(currentTierPreference).isEmpty()) {
-                    String newTierPreference = isDataStreamIndex ? DataTier.DATA_HOT : DataTier.DATA_CONTENT;
-                    logger.debug("enforcing default [{}] setting for [{}] creation, replacing [{}] with [{}]",
-                        DataTier.TIER_PREFERENCE, request.index(), currentTierPreference, newTierPreference);
-                    indexSettingsBuilder.put(DataTier.TIER_PREFERENCE, newTierPreference);
-                }
+            // regardless of any previous logic, we're going to force there
+            // to be an appropriate non-empty value for the tier preference
+            String currentTierPreference = indexSettingsBuilder.get(DataTier.TIER_PREFERENCE);
+            if (DataTier.parseTierList(currentTierPreference).isEmpty()) {
+                String newTierPreference = isDataStreamIndex ? DataTier.DATA_HOT : DataTier.DATA_CONTENT;
+                logger.debug("enforcing default [{}] setting for [{}] creation, replacing [{}] with [{}]",
+                    DataTier.TIER_PREFERENCE, request.index(), currentTierPreference, newTierPreference);
+                indexSettingsBuilder.put(DataTier.TIER_PREFERENCE, newTierPreference);
             }
         }
 

server/src/main/java/org/elasticsearch/cluster/routing/allocation/DataTier.java

@@ -45,12 +45,13 @@ public class DataTier {
 
     public static final Set<String> ALL_DATA_TIERS = Set.of(DATA_CONTENT, DATA_HOT, DATA_WARM, DATA_COLD, DATA_FROZEN);
 
-    // this setting is for migrating from 7.x (where a tier preference was not required, and did not necessarily
+    // deprecated setting for migrating from 7.x (where a tier preference was not required, and did not necessarily
     // have a default value), to 8.x (where a tier preference will be required, and a default value will be injected).
-    // it will be removed as a breaking change in some future version, likely 9.0.
+    // in version 8.0 and onward, this setting doesn't control any logic anymore, and it will be removed as a breaking change in
+    // some future version, likely 9.0.
     public static final String ENFORCE_DEFAULT_TIER_PREFERENCE = "cluster.routing.allocation.enforce_default_tier_preference";
     public static final Setting<Boolean> ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING =
-        Setting.boolSetting(ENFORCE_DEFAULT_TIER_PREFERENCE, true, Property.Dynamic, Property.NodeScope);
+        Setting.boolSetting(ENFORCE_DEFAULT_TIER_PREFERENCE, true, Property.Dynamic, Property.NodeScope, Property.Deprecated);
 
     public static final String TIER_PREFERENCE = "index.routing.allocation.include._tier_preference";
 

server/src/main/java/org/elasticsearch/cluster/routing/allocation/decider/DiskThresholdDecider.java

@@ -25,7 +25,6 @@
 import org.elasticsearch.cluster.routing.allocation.RoutingAllocation;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.collect.ImmutableOpenMap;
-import org.elasticsearch.common.logging.DeprecationLogger;
 import org.elasticsearch.common.settings.ClusterSettings;
 import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Settings;
@@ -66,7 +65,6 @@
 public class DiskThresholdDecider extends AllocationDecider {
 
     private static final Logger logger = LogManager.getLogger(DiskThresholdDecider.class);
-    private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(DiskThresholdDecider.class);
 
     public static final String NAME = "disk_threshold";
 

server/src/test/java/org/elasticsearch/cluster/metadata/MetadataCreateIndexServiceTests.java

@@ -581,7 +581,7 @@ public void testAggregateSettingsAppliesSettingsFromTemplatesAndRequest() {
 
         Settings aggregatedIndexSettings = aggregateIndexSettings(clusterState, request, templateMetadata.settings(),
             null, Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(),
-            Collections.emptySet(), randomBoolean());
+            Collections.emptySet());
 
         assertThat(aggregatedIndexSettings.get("template_setting"), equalTo("value1"));
         assertThat(aggregatedIndexSettings.get("request_setting"), equalTo("value2"));
@@ -634,7 +634,7 @@ public void testRequestDataHavePriorityOverTemplateData() throws Exception {
 
         Settings aggregatedIndexSettings = aggregateIndexSettings(ClusterState.EMPTY_STATE, request, templateMetadata.settings(),
             null, Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(),
-            Collections.emptySet(), randomBoolean());
+            Collections.emptySet());
 
         assertThat(resolvedAliases.get(0).getSearchRouting(), equalTo("fromRequest"));
         assertThat(aggregatedIndexSettings.get("key1"), equalTo("requestValue"));
@@ -649,15 +649,15 @@ null, Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLi
     public void testDefaultSettings() {
         Settings aggregatedIndexSettings = aggregateIndexSettings(ClusterState.EMPTY_STATE, request, Settings.EMPTY,
             null, Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(),
-            Collections.emptySet(), randomBoolean());
+            Collections.emptySet());
 
         assertThat(aggregatedIndexSettings.get(SETTING_NUMBER_OF_SHARDS), equalTo("1"));
     }
 
     public void testSettingsFromClusterState() {
         Settings aggregatedIndexSettings = aggregateIndexSettings(ClusterState.EMPTY_STATE, request, Settings.EMPTY,
             null, Settings.builder().put(SETTING_NUMBER_OF_SHARDS, 15).build(), IndexScopedSettings.DEFAULT_SCOPED_SETTINGS,
-            randomShardLimitService(), Collections.emptySet(), randomBoolean());
+            randomShardLimitService(), Collections.emptySet());
 
         assertThat(aggregatedIndexSettings.get(SETTING_NUMBER_OF_SHARDS), equalTo("15"));
     }
@@ -682,7 +682,7 @@ public void testTemplateOrder() throws  Exception {
 
         Settings aggregatedIndexSettings = aggregateIndexSettings(ClusterState.EMPTY_STATE, request,
             MetadataIndexTemplateService.resolveSettings(templates), null, Settings.EMPTY,
-            IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(), Collections.emptySet(), randomBoolean());
+            IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(), Collections.emptySet());
         List<AliasMetadata> resolvedAliases = resolveAndValidateAliases(request.index(), request.aliases(),
             MetadataIndexTemplateService.resolveAliases(templates),
             Metadata.builder().build(), aliasValidator, xContentRegistry(), searchExecutionContext,
@@ -740,7 +740,7 @@ public void testAggregateIndexSettingsIgnoresTemplatesOnCreateFromSourceIndex()
 
         Settings aggregatedIndexSettings = aggregateIndexSettings(clusterState, request, templateMetadata.settings(),
             clusterState.metadata().index("sourceIndex"), Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS,
-            randomShardLimitService(), Collections.emptySet(), randomBoolean());
+            randomShardLimitService(), Collections.emptySet());
 
         assertThat(aggregatedIndexSettings.get("templateSetting"), is(nullValue()));
         assertThat(aggregatedIndexSettings.get("requestSetting"), is("requestValue"));
@@ -943,8 +943,7 @@ public void testGetIndexNumberOfRoutingShardsYieldsSourceNumberOfShards() {
         assertThat(targetRoutingNumberOfShards, is(6));
     }
 
-    private Optional<String> aggregatedTierPreference(Settings settings, boolean isDataStream,
-                                                      boolean enforceDefaultTierPreference) {
+    private Optional<String> aggregatedTierPreference(Settings settings, boolean isDataStream) {
         Settings templateSettings = Settings.EMPTY;
         request.settings(Settings.EMPTY);
 
@@ -961,7 +960,7 @@ private Optional<String> aggregatedTierPreference(Settings settings, boolean isD
         }
         Settings aggregatedIndexSettings = aggregateIndexSettings(ClusterState.EMPTY_STATE, request, templateSettings,
             null, Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(),
-            Set.of(new DataTier.DefaultHotAllocationSettingProvider()), enforceDefaultTierPreference);
+            Set.of(new DataTier.DefaultHotAllocationSettingProvider()));
 
         if (aggregatedIndexSettings.keySet().contains(DataTier.TIER_PREFERENCE)) {
             return Optional.of(aggregatedIndexSettings.get(DataTier.TIER_PREFERENCE));
@@ -976,45 +975,36 @@ public void testEnforceDefaultTierPreference() {
 
         // empty settings gets the appropriate tier
         settings = Settings.EMPTY;
-        tier = aggregatedTierPreference(settings, false, randomBoolean());
+        tier = aggregatedTierPreference(settings, false);
         assertEquals(DataTier.DATA_CONTENT, tier.get());
 
         settings = Settings.EMPTY;
-        tier = aggregatedTierPreference(settings, true, randomBoolean());
+        tier = aggregatedTierPreference(settings, true);
         assertEquals(DataTier.DATA_HOT, tier.get());
 
         // an explicit tier is respected
         settings = Settings.builder().put(DataTier.TIER_PREFERENCE, DataTier.DATA_COLD).build();
-        tier = aggregatedTierPreference(settings, randomBoolean(), randomBoolean());
+        tier = aggregatedTierPreference(settings, randomBoolean());
         assertEquals(DataTier.DATA_COLD, tier.get());
 
-        // any of the INDEX_ROUTING_.*_GROUP_PREFIX settings still result in a default if
-        // we're enforcing
+        // any of the INDEX_ROUTING_.*_GROUP_PREFIX settings still result in a default
         String includeRoutingSetting = randomFrom(
             IndexMetadata.INDEX_ROUTING_REQUIRE_GROUP_PREFIX,
             IndexMetadata.INDEX_ROUTING_EXCLUDE_GROUP_PREFIX,
             IndexMetadata.INDEX_ROUTING_INCLUDE_GROUP_PREFIX) + "." + randomAlphaOfLength(10);
         settings = Settings.builder()
             .put(includeRoutingSetting, randomAlphaOfLength(10))
             .build();
-        tier = aggregatedTierPreference(settings, false, true);
+        tier = aggregatedTierPreference(settings, false);
         assertEquals(DataTier.DATA_CONTENT, tier.get());
-        // (continued from above) but not if we aren't
-        tier = aggregatedTierPreference(settings, false, false);
-        assertTrue(tier.isEmpty());
 
-        // an explicit null gets an empty tier if we're not enforcing
+        // an explicit null gets the appropriate tier
         settings = Settings.builder().putNull(DataTier.TIER_PREFERENCE).build();
-        tier = aggregatedTierPreference(settings, randomBoolean(), false);
-        assertTrue(tier.isEmpty());
-
-        // an explicit null gets the appropriate tier if we are enforcing
-        settings = Settings.builder().putNull(DataTier.TIER_PREFERENCE).build();
-        tier = aggregatedTierPreference(settings, false, true);
+        tier = aggregatedTierPreference(settings, false);
         assertEquals(DataTier.DATA_CONTENT, tier.get());
 
         settings = Settings.builder().putNull(DataTier.TIER_PREFERENCE).build();
-        tier = aggregatedTierPreference(settings, true, true);
+        tier = aggregatedTierPreference(settings, true);
         assertEquals(DataTier.DATA_HOT, tier.get());
     }
 
@@ -1024,7 +1014,7 @@ public void testRejectWithSoftDeletesDisabled() {
             request.settings(Settings.builder().put(INDEX_SOFT_DELETES_SETTING.getKey(), false).build());
             aggregateIndexSettings(ClusterState.EMPTY_STATE, request, Settings.EMPTY,
                 null, Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(),
-                Collections.emptySet(), randomBoolean());
+                Collections.emptySet());
         });
         assertThat(error.getMessage(), equalTo("Creating indices with soft-deletes disabled is no longer supported. "
             + "Please do not specify a value for setting [index.soft_deletes.enabled]."));
@@ -1046,7 +1036,7 @@ public void testRejectTranslogRetentionSettings() {
         IllegalArgumentException error = expectThrows(IllegalArgumentException.class,
             () -> aggregateIndexSettings(ClusterState.EMPTY_STATE, request, Settings.EMPTY,
                 null, Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(),
-                Collections.emptySet(), randomBoolean()));
+                Collections.emptySet()));
         assertThat(error.getMessage(), equalTo("Translog retention settings [index.translog.retention.age] " +
             "and [index.translog.retention.size] are no longer supported. Please do not specify values for these settings"));
     }
@@ -1063,7 +1053,7 @@ public void testDeprecateTranslogRetentionSettings() {
         request.settings(settings.build());
         aggregateIndexSettings(ClusterState.EMPTY_STATE, request, Settings.EMPTY,
             null, Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(),
-            Collections.emptySet(), randomBoolean());
+            Collections.emptySet());
         assertWarnings("Translog retention settings [index.translog.retention.age] "
             + "and [index.translog.retention.size] are deprecated and effectively ignored. They will be removed in a future version.");
     }
@@ -1076,7 +1066,7 @@ public void testDeprecateSimpleFS() {
         request.settings(settings.build());
         aggregateIndexSettings(ClusterState.EMPTY_STATE, request, Settings.EMPTY,
             null, Settings.EMPTY, IndexScopedSettings.DEFAULT_SCOPED_SETTINGS, randomShardLimitService(),
-            Collections.emptySet(), randomBoolean());
+            Collections.emptySet());
         assertWarnings("[simplefs] is deprecated and will be removed in 8.0. Use [niofs] or other file systems instead. " +
             "Elasticsearch 7.15 or later uses [niofs] for the [simplefs] store type " +
             "as it offers superior or equivalent performance to [simplefs].");