[8.7] Route term vectors requests to promotable copies (#94257)

server/src/main/java/org/elasticsearch/action/get/TransportGetAction.java

@@ -13,10 +13,7 @@
 import org.elasticsearch.action.support.single.shard.TransportSingleShardAction;
 import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
-import org.elasticsearch.cluster.node.DiscoveryNode;
-import org.elasticsearch.cluster.routing.PlainShardIterator;
 import org.elasticsearch.cluster.routing.ShardIterator;
-import org.elasticsearch.cluster.routing.ShardRouting;
 import org.elasticsearch.cluster.service.ClusterService;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.io.stream.Writeable;
@@ -30,7 +27,6 @@
 import org.elasticsearch.transport.TransportService;
 
 import java.io.IOException;
-import java.util.stream.Collectors;
 
 /**
  * Performs the get operation.
@@ -79,19 +75,7 @@ protected ShardIterator shards(ClusterState state, InternalRequest request) {
                 request.request().routing(),
                 request.request().preference()
             );
-        if (iterator == null) {
-            return null;
-        }
-        // If it is stateless, only route isPromotableToPrimary shards. This is a temporary workaround until a more cohesive solution can be
-        // implemented for search shards.
-        if (DiscoveryNode.isStateless(clusterService.getSettings())) {
-            return new PlainShardIterator(
-                iterator.shardId(),
-                iterator.getShardRoutings().stream().filter(ShardRouting::isPromotableToPrimary).collect(Collectors.toList())
-            );
-        } else {
-            return iterator;
-        }
+        return clusterService.operationRouting().useOnlyPromotableShardsForStateless(iterator);
     }
 
     @Override

server/src/main/java/org/elasticsearch/action/get/TransportShardMultiGetAction.java

@@ -15,10 +15,7 @@
 import org.elasticsearch.action.support.single.shard.TransportSingleShardAction;
 import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.cluster.metadata.IndexNameExpressionResolver;
-import org.elasticsearch.cluster.node.DiscoveryNode;
-import org.elasticsearch.cluster.routing.PlainShardIterator;
 import org.elasticsearch.cluster.routing.ShardIterator;
-import org.elasticsearch.cluster.routing.ShardRouting;
 import org.elasticsearch.cluster.service.ClusterService;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.io.stream.Writeable;
@@ -32,7 +29,6 @@
 import org.elasticsearch.transport.TransportService;
 
 import java.io.IOException;
-import java.util.stream.Collectors;
 
 import static org.elasticsearch.core.Strings.format;
 
@@ -87,19 +83,7 @@ protected boolean resolveIndex(MultiGetShardRequest request) {
     protected ShardIterator shards(ClusterState state, InternalRequest request) {
         ShardIterator iterator = clusterService.operationRouting()
             .getShards(state, request.request().index(), request.request().shardId(), request.request().preference());
-        if (iterator == null) {
-            return null;
-        }
-        // If it is stateless, only route promotable shards. This is a temporary workaround until a more cohesive solution can be
-        // implemented for search shards.
-        if (DiscoveryNode.isStateless(clusterService.getSettings())) {
-            return new PlainShardIterator(
-                iterator.shardId(),
-                iterator.getShardRoutings().stream().filter(ShardRouting::isPromotableToPrimary).collect(Collectors.toList())
-            );
-        } else {
-            return iterator;
-        }
+        return clusterService.operationRouting().useOnlyPromotableShardsForStateless(iterator);
     }
 
     @Override

server/src/main/java/org/elasticsearch/action/termvectors/TransportShardMultiTermsVectorAction.java

@@ -76,8 +76,9 @@ protected boolean resolveIndex(MultiTermVectorsShardRequest request) {
 
     @Override
     protected ShardIterator shards(ClusterState state, InternalRequest request) {
-        return clusterService.operationRouting()
+        ShardIterator shards = clusterService.operationRouting()
             .getShards(state, request.concreteIndex(), request.request().shardId(), request.request().preference());
+        return clusterService.operationRouting().useOnlyPromotableShardsForStateless(shards);
     }
 
     @Override

server/src/main/java/org/elasticsearch/action/termvectors/TransportTermVectorsAction.java

@@ -67,8 +67,9 @@ protected ShardIterator shards(ClusterState state, InternalRequest request) {
             return groupShardsIter.iterator().next();
         }
 
-        return clusterService.operationRouting()
+        ShardIterator shards = clusterService.operationRouting()
             .getShards(state, request.concreteIndex(), request.request().id(), request.request().routing(), request.request().preference());
+        return clusterService.operationRouting().useOnlyPromotableShardsForStateless(shards);
     }
 
     @Override

server/src/main/java/org/elasticsearch/cluster/routing/OperationRouting.java

@@ -10,6 +10,7 @@
 
 import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.cluster.metadata.IndexMetadata;
+import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.cluster.node.DiscoveryNodes;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.settings.ClusterSettings;
@@ -39,8 +40,10 @@ public class OperationRouting {
     );
 
     private boolean useAdaptiveReplicaSelection;
+    private final boolean isStateless;
 
     public OperationRouting(Settings settings, ClusterSettings clusterSettings) {
+        this.isStateless = DiscoveryNode.isStateless(settings);
         this.useAdaptiveReplicaSelection = USE_ADAPTIVE_REPLICA_SELECTION_SETTING.get(settings);
         clusterSettings.addSettingsUpdateConsumer(USE_ADAPTIVE_REPLICA_SELECTION_SETTING, this::setUseAdaptiveReplicaSelection);
     }
@@ -76,6 +79,19 @@ public ShardIterator getShards(ClusterState clusterState, String index, int shar
         );
     }
 
+    public ShardIterator useOnlyPromotableShardsForStateless(ShardIterator shards) {
+        // If it is stateless, only route promotable shards. This is a temporary workaround until a more cohesive solution can be
+        // implemented for search shards.
+        if (isStateless && shards != null) {
+            return new PlainShardIterator(
+                shards.shardId(),
+                shards.getShardRoutings().stream().filter(ShardRouting::isPromotableToPrimary).collect(Collectors.toList())
+            );
+        } else {
+            return shards;
+        }
+    }
+
     public GroupShardsIterator<ShardIterator> searchShards(
         ClusterState clusterState,
         String[] concreteIndices,