refactor health service creation (#83831)

This commit extracts health service creation into a separate method in
order to reduce overall service wiring method complexity

Author: idegtiarenko

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

@@ -96,7 +96,6 @@
 import org.elasticsearch.gateway.GatewayService;
 import org.elasticsearch.gateway.MetaStateService;
 import org.elasticsearch.gateway.PersistedClusterStateService;
-import org.elasticsearch.health.HealthIndicatorService;
 import org.elasticsearch.health.HealthService;
 import org.elasticsearch.http.HttpServerTransport;
 import org.elasticsearch.index.IndexSettingProviders;
@@ -865,7 +864,7 @@ protected Node(
                 metadataCreateIndexService,
                 settingsModule.getIndexScopedSettings()
             );
-            final List<PersistentTasksExecutor<?>> builtinTaskExecutors = Arrays.asList(systemIndexMigrationExecutor);
+            final List<PersistentTasksExecutor<?>> builtinTaskExecutors = List.of(systemIndexMigrationExecutor);
             final List<PersistentTasksExecutor<?>> pluginTaskExectors = pluginsService.filterPlugins(PersistentTaskPlugin.class)
                 .stream()
                 .map(
@@ -879,10 +878,9 @@ protected Node(
                 )
                 .flatMap(List::stream)
                 .collect(toList());
-            final List<PersistentTasksExecutor<?>> allTasksExectors = Stream.of(pluginTaskExectors, builtinTaskExecutors)
-                .flatMap(List::stream)
-                .collect(toList());
-            final PersistentTasksExecutorRegistry registry = new PersistentTasksExecutorRegistry(allTasksExectors);
+            final PersistentTasksExecutorRegistry registry = new PersistentTasksExecutorRegistry(
+                concatLists(pluginTaskExectors, builtinTaskExecutors)
+            );
             final PersistentTasksClusterService persistentTasksClusterService = new PersistentTasksClusterService(
                 settings,
                 registry,
@@ -901,15 +899,7 @@ protected Node(
                 clusterService.getClusterSettings()
             );
 
-            List<HealthIndicatorService> serverHealthIndicatorServices = List.of(
-                new InstanceHasMasterHealthIndicatorService(clusterService),
-                new RepositoryIntegrityHealthIndicatorService(clusterService)
-            );
-            List<HealthIndicatorService> pluginHealthIndicatorServices = pluginsService.filterPlugins(HealthPlugin.class)
-                .stream()
-                .flatMap(plugin -> plugin.getHealthIndicatorServices().stream())
-                .toList();
-            HealthService healthService = new HealthService(concatLists(serverHealthIndicatorServices, pluginHealthIndicatorServices));
+            HealthService healthService = createHealthService(clusterService);
 
             modules.add(b -> {
                 b.bind(Node.class).toInstance(this);
@@ -1042,6 +1032,18 @@ protected Node(
         }
     }
 
+    private HealthService createHealthService(ClusterService clusterService) {
+        var serverHealthIndicatorServices = List.of(
+            new InstanceHasMasterHealthIndicatorService(clusterService),
+            new RepositoryIntegrityHealthIndicatorService(clusterService)
+        );
+        var pluginHealthIndicatorServices = pluginsService.filterPlugins(HealthPlugin.class)
+            .stream()
+            .flatMap(plugin -> plugin.getHealthIndicatorServices().stream())
+            .toList();
+        return new HealthService(concatLists(serverHealthIndicatorServices, pluginHealthIndicatorServices));
+    }
+
     private RecoveryPlannerService getRecoveryPlannerService(
         ThreadPool threadPool,
         ClusterService clusterService,
@@ -1062,8 +1064,7 @@ private RecoveryPlannerService getRecoveryPlannerService(
             threadPool,
             clusterService
         );
-        final RecoveryPlannerPlugin recoveryPlannerPlugin = recoveryPlannerPlugins.get(0);
-        return recoveryPlannerPlugin.createRecoveryPlannerService(shardSnapshotsService);
+        return recoveryPlannerPlugins.get(0).createRecoveryPlannerService(shardSnapshotsService);
     }
 
     protected TransportService newTransportService(