Move IndicesService.canDeleteShardContent to use IndexSettings

Just a minor cleanup/simplification

Closes #15059
Closes #15150

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

@@ -461,7 +461,7 @@ public class IndicesService extends AbstractLifecycleComponent<IndicesService> i
 
     /**
      * This method deletes the shard contents on disk for the given shard ID. This method will fail if the shard deleting
-     * is prevented by {@link #canDeleteShardContent(org.elasticsearch.index.shard.ShardId, org.elasticsearch.cluster.metadata.IndexMetaData)}
+     * is prevented by {@link #canDeleteShardContent(ShardId, IndexSettings)}
      * of if the shards lock can not be acquired.
      *
      * On data nodes, if the deleted shard is the last shard folder in its index, the method will attempt to remove the index folder as well.
@@ -529,18 +529,10 @@ public class IndicesService extends AbstractLifecycleComponent<IndicesService> i
      * </ul>
      *
      * @param shardId the shard to delete.
-     * @param metaData the shards index metadata. This is required to access the indexes settings etc.
+     * @param indexSettings the shards's relevant {@link IndexSettings}. This is required to access the indexes settings etc.
      */
-    public boolean canDeleteShardContent(ShardId shardId, IndexMetaData metaData) {
+    public boolean canDeleteShardContent(ShardId shardId, IndexSettings indexSettings) {
-        // we need the metadata here since we have to build the complete settings
+        assert shardId.getIndex().equals(indexSettings.getIndex().name());
-        // to decide where the shard content lives. In the future we might even need more info here ie. for shadow replicas
-        // The plan was to make it harder to miss-use and ask for metadata instead of simple settings
-        assert shardId.getIndex().equals(metaData.getIndex());
-        final IndexSettings indexSettings = buildIndexSettings(metaData);
-        return canDeleteShardContent(shardId, indexSettings);
-    }
-
-    private boolean canDeleteShardContent(ShardId shardId, IndexSettings indexSettings) {
         final IndexService indexService = this.indices.get(shardId.getIndex());
         if (indexSettings.isOnSharedFilesystem() == false) {
             if (indexService != null && nodeEnv.hasNodeFile()) {

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

@@ -33,6 +33,7 @@ import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.common.util.concurrent.EsRejectedExecutionException;
 import org.elasticsearch.index.IndexService;
+import org.elasticsearch.index.IndexSettings;
 import org.elasticsearch.index.shard.IndexShard;
 import org.elasticsearch.index.shard.IndexShardState;
 import org.elasticsearch.index.shard.ShardId;
@@ -43,6 +44,7 @@ import org.elasticsearch.transport.*;
 import java.io.Closeable;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.EnumSet;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
@@ -97,11 +99,12 @@ public class IndicesStore extends AbstractComponent implements ClusterStateListe
         }
 
         for (IndexRoutingTable indexRoutingTable : event.state().routingTable()) {
+            IndexSettings indexSettings = new IndexSettings(event.state().getMetaData().index(indexRoutingTable.index()), settings, Collections.emptyList());
             // Note, closed indices will not have any routing information, so won't be deleted
             for (IndexShardRoutingTable indexShardRoutingTable : indexRoutingTable) {
                 if (shardCanBeDeleted(event.state(), indexShardRoutingTable)) {
                     ShardId shardId = indexShardRoutingTable.shardId();
-                    if (indicesService.canDeleteShardContent(shardId, event.state().getMetaData().index(shardId.getIndex()))) {
+                    if (indicesService.canDeleteShardContent(shardId, indexSettings)) {
                         deleteShardIfExistElseWhere(event.state(), indexShardRoutingTable);
                     }
                 }

core/src/test/java/org/elasticsearch/indices/IndicesServiceTests.java

@@ -72,12 +72,13 @@ public class IndicesServiceTests extends ESSingleNodeTestCase {
         IndicesService indicesService = getIndicesService();
         IndexMetaData meta = IndexMetaData.builder("test").settings(settings(Version.CURRENT)).numberOfShards(1).numberOfReplicas(
                 1).build();
-        assertFalse("no shard location", indicesService.canDeleteShardContent(new ShardId("test", 0), meta));
+        IndexSettings indexSettings = IndexSettingsModule.newIndexSettings("test", meta.getSettings());
+        assertFalse("no shard location", indicesService.canDeleteShardContent(new ShardId("test", 0), indexSettings));
         IndexService test = createIndex("test");
         assertTrue(test.hasShard(0));
-        assertFalse("shard is allocated", indicesService.canDeleteShardContent(new ShardId("test", 0), meta));
+        assertFalse("shard is allocated", indicesService.canDeleteShardContent(new ShardId("test", 0), indexSettings));
         test.removeShard(0, "boom");
-        assertTrue("shard is removed", indicesService.canDeleteShardContent(new ShardId("test", 0), meta));
+        assertTrue("shard is removed", indicesService.canDeleteShardContent(new ShardId("test", 0), indexSettings));
     }
 
     public void testDeleteIndexStore() throws Exception {