Always enforce a default tier preference (ENFORCE_DEFAULT_TIER_PREFERENCE must always be true)

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

@@ -158,6 +158,8 @@ public MetadataCreateIndexService(
         this.shardLimitValidator = shardLimitValidator;
 
         enforceDefaultTierPreference = DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING.get(settings);
+        assert enforceDefaultTierPreference;
+
         clusterService.getClusterSettings().addSettingsUpdateConsumer(DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING,
             this::setEnforceDefaultTierPreference);
     }

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

@@ -17,6 +17,7 @@
 import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Setting.Property;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.settings.SettingsException;
 import org.elasticsearch.index.IndexModule;
 import org.elasticsearch.index.shard.IndexSettingProvider;
 import org.elasticsearch.snapshots.SearchableSnapshotsSettings;
@@ -50,7 +51,17 @@ public class DataTier {
     // 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,
+            new Setting.Validator<>() {
+                @Override
+                public void validate(Boolean value) {
+                    if (value != Boolean.TRUE) {
+                        throw new SettingsException("setting [{}={}}] is not allowed, only true is valid",
+                            ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING.getKey(), value);
+                    }
+                }
+            },
+            Property.Dynamic, Property.NodeScope);
 
     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";
 

test/framework/src/main/java/org/elasticsearch/test/ESIntegTestCase.java

@@ -37,6 +37,7 @@
 import org.elasticsearch.action.admin.indices.segments.IndexShardSegments;
 import org.elasticsearch.action.admin.indices.segments.IndicesSegmentResponse;
 import org.elasticsearch.action.admin.indices.segments.ShardSegments;
+import org.elasticsearch.action.admin.indices.settings.put.UpdateSettingsRequestBuilder;
 import org.elasticsearch.action.admin.indices.template.put.PutIndexTemplateRequestBuilder;
 import org.elasticsearch.action.bulk.BulkRequestBuilder;
 import org.elasticsearch.action.bulk.BulkResponse;
@@ -68,7 +69,6 @@
 import org.elasticsearch.cluster.routing.IndexShardRoutingTable;
 import org.elasticsearch.cluster.routing.ShardRouting;
 import org.elasticsearch.cluster.routing.UnassignedInfo;
-import org.elasticsearch.cluster.routing.allocation.DataTier;
 import org.elasticsearch.cluster.routing.allocation.DiskThresholdSettings;
 import org.elasticsearch.cluster.routing.allocation.decider.EnableAllocationDecider;
 import org.elasticsearch.cluster.service.ClusterService;
@@ -781,6 +781,15 @@ public CreateIndexRequestBuilder prepareCreate(String index, int numNodes, Setti
         return client().admin().indices().prepareCreate(index).setSettings(builder.build());
     }
 
+    /**
+     * updates the settings for an index
+     */
+    public void updateIndexSettings(String index, Settings.Builder settingsBuilder) {
+        UpdateSettingsRequestBuilder settingsRequest = client().admin().indices().prepareUpdateSettings(index);
+        settingsRequest.setSettings(settingsBuilder);
+        assertAcked(settingsRequest.execute().actionGet());
+    }
+
     private Settings.Builder getExcludeSettings(int num, Settings.Builder builder) {
         String exclude = String.join(",", internalCluster().allDataNodesButN(num));
         builder.put("index.routing.allocation.exclude._name", exclude);
@@ -1756,8 +1765,6 @@ protected Settings nodeSettings(int nodeOrdinal, Settings otherSettings) {
             .put(IndicesStore.INDICES_STORE_DELETE_SHARD_TIMEOUT.getKey(), new TimeValue(1, TimeUnit.SECONDS))
             // randomly enable low-level search cancellation to make sure it does not alter results
             .put(SearchService.LOW_LEVEL_CANCELLATION_SETTING.getKey(), randomBoolean())
-            // randomly enable enforcing a default tier_preference to make sure it does not alter results
-            .put(DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING.getKey(), randomBoolean())
             .putList(DISCOVERY_SEED_HOSTS_SETTING.getKey()) // empty list disables a port scan for other nodes
             .putList(DISCOVERY_SEED_PROVIDERS_SETTING.getKey(), "file")
             .put(TransportSearchAction.DEFAULT_PRE_FILTER_SHARD_SIZE.getKey(), randomFrom(1, 2,

x-pack/plugin/autoscaling/src/internalClusterTest/java/org/elasticsearch/xpack/autoscaling/storage/ReactiveStorageIT.java

@@ -7,7 +7,6 @@
 
 package org.elasticsearch.xpack.autoscaling.storage;
 
-import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsRequest;
 import org.elasticsearch.action.admin.indices.settings.put.UpdateSettingsRequest;
 import org.elasticsearch.action.admin.indices.stats.IndicesStatsResponse;
 import org.elasticsearch.action.index.IndexRequestBuilder;
@@ -152,10 +151,6 @@ public void testScaleFromEmptyLegacy() {
             )
         );
 
-        // if we inject a default tier preference, then this test wouldn't be valid anymore,
-        // so let's turn that off
-        enforceDefaultTierPreference(false);
-
         putAutoscalingPolicy("hot", DataTier.DATA_HOT);
         putAutoscalingPolicy("warm", DataTier.DATA_WARM);
         putAutoscalingPolicy("cold", DataTier.DATA_COLD);
@@ -185,6 +180,10 @@ public void testScaleFromEmptyLegacy() {
                     .build()
             )
         );
+
+        // the tier preference will have defaulted to data_content, set it back to null
+        updateIndexSettings(indexName, Settings.builder().putNull(DataTier.TIER_PREFERENCE));
+
         refresh(indexName);
         assertThat(capacity().results().get("warm").requiredCapacity().total().storage().getBytes(), Matchers.equalTo(0L));
         assertThat(capacity().results().get("cold").requiredCapacity().total().storage().getBytes(), Matchers.equalTo(0L));
@@ -249,10 +248,4 @@ private void putAutoscalingPolicy(String policyName, String role) {
         );
         assertAcked(client().execute(PutAutoscalingPolicyAction.INSTANCE, request).actionGet());
     }
-
-    public void enforceDefaultTierPreference(boolean enforceDefaultTierPreference) {
-        ClusterUpdateSettingsRequest request = new ClusterUpdateSettingsRequest();
-        request.transientSettings(Settings.builder().put(DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE, enforceDefaultTierPreference).build());
-        assertAcked(client().admin().cluster().updateSettings(request).actionGet());
-    }
 }

x-pack/plugin/core/src/internalClusterTest/java/org/elasticsearch/xpack/cluster/routing/allocation/DataTierAllocationDeciderIT.java

@@ -7,18 +7,17 @@
 
 package org.elasticsearch.xpack.cluster.routing.allocation;
 
-import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsRequest;
 import org.elasticsearch.action.admin.indices.settings.put.UpdateSettingsRequest;
 import org.elasticsearch.action.admin.indices.shrink.ResizeType;
 import org.elasticsearch.action.admin.indices.template.put.PutComposableIndexTemplateAction;
 import org.elasticsearch.cluster.health.ClusterHealthStatus;
 import org.elasticsearch.cluster.metadata.ComposableIndexTemplate;
 import org.elasticsearch.cluster.metadata.IndexMetadata;
 import org.elasticsearch.cluster.metadata.Template;
+import org.elasticsearch.cluster.routing.allocation.DataTier;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.test.ESIntegTestCase;
-import org.elasticsearch.cluster.routing.allocation.DataTier;
 import org.elasticsearch.xpack.core.DataTiersFeatureSetUsage;
 import org.elasticsearch.xpack.core.action.XPackUsageRequestBuilder;
 import org.elasticsearch.xpack.core.action.XPackUsageResponse;
@@ -28,7 +27,6 @@
 import java.util.Collections;
 import java.util.Map;
 
-import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAcked;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.greaterThanOrEqualTo;
 
@@ -86,51 +84,9 @@ public void testOverrideDefaultAllocation() {
         ensureYellow(index);
     }
 
-    public void testRequestSettingOverridesAllocation() {
-        startWarmOnlyNode();
-        startColdOnlyNode();
-        ensureGreen();
-        enforceDefaultTierPreference(false);
-
-        client().admin().indices().prepareCreate(index)
-            .setWaitForActiveShards(0)
-            .setSettings(Settings.builder()
-                .putNull(DataTier.TIER_PREFERENCE))
-            .get();
-
-        Settings idxSettings = client().admin().indices().prepareGetIndex().addIndices(index).get().getSettings().get(index);
-        assertThat(DataTier.TIER_PREFERENCE_SETTING.get(idxSettings), equalTo(""));
-        // Even the key shouldn't exist if it has been nulled out
-        assertFalse(idxSettings.keySet().toString(), idxSettings.keySet().contains(DataTier.TIER_PREFERENCE));
-
-        // index should be yellow
-        logger.info("--> waiting for {} to be yellow", index);
-        ensureYellow(index);
-
-        client().admin().indices().prepareDelete(index).get();
-
-        // Now test it overriding the "require" setting, in which case the preference should be skipped
-        client().admin().indices().prepareCreate(index)
-            .setWaitForActiveShards(0)
-            .setSettings(Settings.builder()
-                .put(IndexMetadata.INDEX_ROUTING_REQUIRE_GROUP_PREFIX + ".box", "cold"))
-            .get();
-
-        idxSettings = client().admin().indices().prepareGetIndex().addIndices(index).get().getSettings().get(index);
-        assertThat(DataTier.TIER_PREFERENCE_SETTING.get(idxSettings), equalTo(""));
-        // The key should not be put in place since it was overridden
-        assertFalse(idxSettings.keySet().contains(DataTier.TIER_PREFERENCE));
-        assertThat(idxSettings.get(IndexMetadata.INDEX_ROUTING_REQUIRE_GROUP_PREFIX + ".box"), equalTo("cold"));
-
-        // index should be yellow
-        logger.info("--> waiting for {} to be yellow", index);
-        ensureYellow(index);
-    }
-
-    public void testRequestSettingOverriddenIfEnforced() {
+    public void testRequestSettingOverridden() {
         startContentOnlyNode();
         ensureGreen();
-        enforceDefaultTierPreference(true);
 
         client().admin().indices().prepareCreate(index)
             .setWaitForActiveShards(0)
@@ -184,48 +140,8 @@ public void testShrinkStaysOnTier() {
             .get();
     }
 
-    public void testTemplateOverridesDefaults() {
-        startWarmOnlyNode();
-        enforceDefaultTierPreference(false);
-
-        Template t = new Template(Settings.builder()
-            .put(IndexMetadata.INDEX_ROUTING_REQUIRE_GROUP_PREFIX + ".box", "warm")
-            .build(), null, null);
-        ComposableIndexTemplate ct = new ComposableIndexTemplate.Builder()
-            .indexPatterns(Collections.singletonList(index))
-            .template(t).build();
-        client().execute(PutComposableIndexTemplateAction.INSTANCE,
-            new PutComposableIndexTemplateAction.Request("template").indexTemplate(ct)).actionGet();
-
-        client().admin().indices().prepareCreate(index).setWaitForActiveShards(0).get();
-
-        Settings idxSettings = client().admin().indices().prepareGetIndex().addIndices(index).get().getSettings().get(index);
-        assertThat(idxSettings.keySet().contains(DataTier.TIER_PREFERENCE), equalTo(false));
-
-        // index should be yellow
-        ensureYellow(index);
-
-        client().admin().indices().prepareDelete(index).get();
-
-        t = new Template(Settings.builder()
-            .putNull(DataTier.TIER_PREFERENCE)
-            .build(), null, null);
-        ct = new ComposableIndexTemplate.Builder().indexPatterns(Collections.singletonList(index))
-                 .template(t).build();
-        client().execute(PutComposableIndexTemplateAction.INSTANCE,
-            new PutComposableIndexTemplateAction.Request("template").indexTemplate(ct)).actionGet();
-
-        client().admin().indices().prepareCreate(index).setWaitForActiveShards(0).get();
-
-        idxSettings = client().admin().indices().prepareGetIndex().addIndices(index).get().getSettings().get(index);
-        assertThat(idxSettings.keySet().contains(DataTier.TIER_PREFERENCE), equalTo(false));
-
-        ensureYellow(index);
-    }
-
-    public void testTemplateOverriddenIfEnforced() {
+    public void testTemplateOverridden() {
         startContentOnlyNode();
-        enforceDefaultTierPreference(true);
 
         Template t = new Template(Settings.builder()
             .putNull(DataTier.TIER_PREFERENCE)
@@ -376,10 +292,4 @@ public void startFrozenOnlyNode() {
             .build();
         internalCluster().startNode(nodeSettings);
     }
-
-    public void enforceDefaultTierPreference(boolean enforceDefaultTierPreference) {
-        ClusterUpdateSettingsRequest request = new ClusterUpdateSettingsRequest();
-        request.transientSettings(Settings.builder().put(DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE, enforceDefaultTierPreference).build());
-        assertAcked(client().admin().cluster().updateSettings(request).actionGet());
-    }
 }

x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/DeprecationChecks.java

@@ -83,7 +83,8 @@ private DeprecationChecks() {
         NodeDeprecationChecks::checkScriptContextCache,
         NodeDeprecationChecks::checkScriptContextCompilationsRateLimitSetting,
         NodeDeprecationChecks::checkScriptContextCacheSizeSetting,
-        NodeDeprecationChecks::checkScriptContextCacheExpirationSetting
+        NodeDeprecationChecks::checkScriptContextCacheExpirationSetting,
+        NodeDeprecationChecks::checkEnforceDefaultTierPreferenceSetting
     );
 
     static List<Function<IndexMetadata, DeprecationIssue>> INDEX_SETTINGS_CHECKS = List.of(

x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/NodeDeprecationChecks.java

@@ -8,6 +8,7 @@
 package org.elasticsearch.xpack.deprecation;
 
 import org.elasticsearch.action.admin.cluster.node.info.PluginsAndModules;
+import org.elasticsearch.cluster.routing.allocation.DataTier;
 import org.elasticsearch.cluster.routing.allocation.decider.DiskThresholdDecider;
 import org.elasticsearch.common.settings.SecureSetting;
 import org.elasticsearch.common.settings.Setting;
@@ -441,4 +442,18 @@ static DeprecationIssue checkScriptContextCacheExpirationSetting(final Settings
         }
         return null;
     }
+
+    static DeprecationIssue checkEnforceDefaultTierPreferenceSetting(final Settings settings, final PluginsAndModules pluginsAndModules) {
+        if (DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING.exists(settings)) {
+            String key = DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING.getKey();
+            return new DeprecationIssue(DeprecationIssue.Level.CRITICAL,
+                String.format(Locale.ROOT, "setting [%s] is deprecated and will not be available in a future version", key),
+                "https://www.elastic.co/guide/en/elasticsearch/reference/current/data-tiers.html",
+                String.format(Locale.ROOT, "found [%s] configured. Discontinue use of this setting.", key),
+                false, null);
+        }
+
+        return null;
+    }
+
 }

x-pack/plugin/deprecation/src/test/java/org/elasticsearch/xpack/deprecation/NodeDeprecationChecksTests.java

@@ -7,6 +7,7 @@
 
 package org.elasticsearch.xpack.deprecation;
 
+import org.elasticsearch.cluster.routing.allocation.DataTier;
 import org.elasticsearch.cluster.routing.allocation.decider.DiskThresholdDecider;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.settings.MockSecureSettings;
@@ -459,4 +460,23 @@ public void testScriptContextCacheExpirationSetting() {
             "[script.context.moving-function.cache_expire] setting was deprecated in Elasticsearch and will be removed in a future" +
                 " release! See the breaking changes documentation for the next major version.");
     }
+
+    public void testEnforceDefaultTierPreferenceSetting() {
+        Settings settings = Settings.builder()
+            .put(DataTier.ENFORCE_DEFAULT_TIER_PREFERENCE_SETTING.getKey(), true)
+            .build();
+
+        List<DeprecationIssue> issues = DeprecationChecks.filterChecks(NODE_SETTINGS_CHECKS, c -> c.apply(settings, null));
+
+        final String expectedUrl = "https://www.elastic.co/guide/en/elasticsearch/reference/current/data-tiers.html";
+        assertThat(issues, hasItem(
+            new DeprecationIssue(DeprecationIssue.Level.CRITICAL,
+                "setting [cluster.routing.allocation.enforce_default_tier_preference] is deprecated and" +
+                    " will not be available in a future version",
+                expectedUrl,
+                "found [cluster.routing.allocation.enforce_default_tier_preference] configured." +
+                    " Discontinue use of this setting.",
+                false, null)));
+    }
+
 }