Initialize startup `CcrRepositories` (#36730)

Currently, the CcrRepositoryManger only listens for settings updates
and installs new repositories. It does not install the repositories that
are in the initial settings. This commit, modifies the manager to
install the initial repositories. Additionally, it modifies the ccr
integration test to configure the remote leader node at startup, instead
of using a settings update.

x-pack/plugin/ccr/src/main/java/org/elasticsearch/xpack/ccr/Ccr.java

@@ -6,7 +6,6 @@
 
 package org.elasticsearch.xpack.ccr;
 
-import org.apache.lucene.util.SetOnce;
 import org.elasticsearch.action.ActionRequest;
 import org.elasticsearch.action.ActionResponse;
 import org.elasticsearch.client.Client;
@@ -111,7 +110,6 @@ public class Ccr extends Plugin implements ActionPlugin, PersistentTaskPlugin, E
     private final boolean enabled;
     private final Settings settings;
     private final CcrLicenseChecker ccrLicenseChecker;
-    private final SetOnce<CcrRepositoryManager> repositoryManager = new SetOnce<>();
     private Client client;
 
     /**
@@ -152,10 +150,9 @@ public class Ccr extends Plugin implements ActionPlugin, PersistentTaskPlugin, E
             return emptyList();
         }
 
-        this.repositoryManager.set(new CcrRepositoryManager(settings, clusterService, client));
-
         return Arrays.asList(
             ccrLicenseChecker,
+            new CcrRepositoryManager(settings, clusterService, client),
             new AutoFollowCoordinator(client, clusterService, ccrLicenseChecker, threadPool::relativeTimeInMillis)
         );
     }

x-pack/plugin/ccr/src/main/java/org/elasticsearch/xpack/ccr/CcrRepositoryManager.java

@@ -10,6 +10,7 @@ import org.elasticsearch.action.ActionRequest;
 import org.elasticsearch.action.support.PlainActionFuture;
 import org.elasticsearch.client.Client;
 import org.elasticsearch.cluster.service.ClusterService;
+import org.elasticsearch.common.component.AbstractLifecycleComponent;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.transport.RemoteClusterAware;
 import org.elasticsearch.xpack.ccr.action.repositories.DeleteInternalCcrRepositoryAction;
@@ -18,31 +19,70 @@ import org.elasticsearch.xpack.ccr.action.repositories.PutInternalCcrRepositoryA
 import org.elasticsearch.xpack.ccr.action.repositories.PutInternalCcrRepositoryRequest;
 import org.elasticsearch.xpack.ccr.repository.CcrRepository;
 
+import java.io.IOException;
 import java.util.List;
+import java.util.Set;
 
-class CcrRepositoryManager extends RemoteClusterAware {
+class CcrRepositoryManager extends AbstractLifecycleComponent {
 
     private final Client client;
+    private final RemoteSettingsUpdateListener updateListener;
 
     CcrRepositoryManager(Settings settings, ClusterService clusterService, Client client) {
         super(settings);
         this.client = client;
-        listenForUpdates(clusterService.getClusterSettings());
+        updateListener = new RemoteSettingsUpdateListener(settings);
+        updateListener.listenForUpdates(clusterService.getClusterSettings());
     }
 
     @Override
-    protected void updateRemoteCluster(String clusterAlias, List<String> addresses, String proxyAddress) {
-        String repositoryName = CcrRepository.NAME_PREFIX + clusterAlias;
-        if (addresses.isEmpty()) {
-            DeleteInternalCcrRepositoryRequest request = new DeleteInternalCcrRepositoryRequest(repositoryName);
-            PlainActionFuture<DeleteInternalCcrRepositoryAction.DeleteInternalCcrRepositoryResponse> f = PlainActionFuture.newFuture();
-            client.execute(DeleteInternalCcrRepositoryAction.INSTANCE, request, f);
-            assert f.isDone() : "Should be completed as it is executed synchronously";
-        } else {
-            ActionRequest request = new PutInternalCcrRepositoryRequest(repositoryName, CcrRepository.TYPE);
-            PlainActionFuture<PutInternalCcrRepositoryAction.PutInternalCcrRepositoryResponse> f = PlainActionFuture.newFuture();
-            client.execute(PutInternalCcrRepositoryAction.INSTANCE, request, f);
-            assert f.isDone() : "Should be completed as it is executed synchronously";
+    protected void doStart() {
+        updateListener.init();
+    }
+
+    @Override
+    protected void doStop() {
+    }
+
+    @Override
+    protected void doClose() throws IOException {
+    }
+
+    private void putRepository(String repositoryName) {
+        ActionRequest request = new PutInternalCcrRepositoryRequest(repositoryName, CcrRepository.TYPE);
+        PlainActionFuture<PutInternalCcrRepositoryAction.PutInternalCcrRepositoryResponse> f = PlainActionFuture.newFuture();
+        client.execute(PutInternalCcrRepositoryAction.INSTANCE, request, f);
+        assert f.isDone() : "Should be completed as it is executed synchronously";
+    }
+
+    private void deleteRepository(String repositoryName) {
+        DeleteInternalCcrRepositoryRequest request = new DeleteInternalCcrRepositoryRequest(repositoryName);
+        PlainActionFuture<DeleteInternalCcrRepositoryAction.DeleteInternalCcrRepositoryResponse> f = PlainActionFuture.newFuture();
+        client.execute(DeleteInternalCcrRepositoryAction.INSTANCE, request, f);
+        assert f.isDone() : "Should be completed as it is executed synchronously";
+    }
+
+    private class RemoteSettingsUpdateListener extends RemoteClusterAware {
+
+        private RemoteSettingsUpdateListener(Settings settings) {
+            super(settings);
+        }
+
+        void init() {
+            Set<String> clusterAliases = buildRemoteClustersDynamicConfig(settings).keySet();
+            for (String clusterAlias : clusterAliases) {
+                putRepository(CcrRepository.NAME_PREFIX + clusterAlias);
+            }
+        }
+
+        @Override
+        protected void updateRemoteCluster(String clusterAlias, List<String> addresses, String proxy) {
+            String repositoryName = CcrRepository.NAME_PREFIX + clusterAlias;
+            if (addresses.isEmpty()) {
+                deleteRepository(repositoryName);
+            } else {
+                putRepository(repositoryName);
+            }
         }
     }
 }

x-pack/plugin/ccr/src/test/java/org/elasticsearch/xpack/CcrIntegTestCase.java

@@ -12,7 +12,6 @@ import org.elasticsearch.action.admin.cluster.health.ClusterHealthResponse;
 import org.elasticsearch.action.admin.cluster.node.tasks.list.ListTasksAction;
 import org.elasticsearch.action.admin.cluster.node.tasks.list.ListTasksRequest;
 import org.elasticsearch.action.admin.cluster.node.tasks.list.ListTasksResponse;
-import org.elasticsearch.action.admin.cluster.settings.ClusterUpdateSettingsRequest;
 import org.elasticsearch.action.admin.indices.get.GetIndexResponse;
 import org.elasticsearch.action.admin.indices.refresh.RefreshResponse;
 import org.elasticsearch.action.admin.indices.settings.put.UpdateSettingsRequest;
@@ -117,27 +116,23 @@ public abstract class CcrIntegTestCase extends ESTestCase {
         }
 
         stopClusters();
-        NodeConfigurationSource nodeConfigurationSource = createNodeConfigurationSource();
         Collection<Class<? extends Plugin>> mockPlugins = Arrays.asList(ESIntegTestCase.TestSeedPlugin.class,
             TestZenDiscovery.TestPlugin.class, MockHttpTransport.TestPlugin.class, getTestTransportPlugin());
 
         InternalTestCluster leaderCluster = new InternalTestCluster(randomLong(), createTempDir(), true, true, numberOfNodesPerCluster(),
-            numberOfNodesPerCluster(), UUIDs.randomBase64UUID(random()), nodeConfigurationSource, 0, "leader", mockPlugins,
+            numberOfNodesPerCluster(), UUIDs.randomBase64UUID(random()), createNodeConfigurationSource(null), 0, "leader", mockPlugins,
             Function.identity());
+        leaderCluster.beforeTest(random(), 0.0D);
+        leaderCluster.ensureAtLeastNumDataNodes(numberOfNodesPerCluster());
+
+        String address = leaderCluster.getDataNodeInstance(TransportService.class).boundAddress().publishAddress().toString();
         InternalTestCluster followerCluster = new InternalTestCluster(randomLong(), createTempDir(), true, true, numberOfNodesPerCluster(),
-            numberOfNodesPerCluster(), UUIDs.randomBase64UUID(random()), nodeConfigurationSource, 0, "follower", mockPlugins,
-            Function.identity());
+            numberOfNodesPerCluster(), UUIDs.randomBase64UUID(random()), createNodeConfigurationSource(address), 0, "follower",
+            mockPlugins, Function.identity());
         clusterGroup = new ClusterGroup(leaderCluster, followerCluster);
 
-        leaderCluster.beforeTest(random(), 0.0D);
-        leaderCluster.ensureAtLeastNumDataNodes(numberOfNodesPerCluster());
         followerCluster.beforeTest(random(), 0.0D);
         followerCluster.ensureAtLeastNumDataNodes(numberOfNodesPerCluster());
-
-        ClusterUpdateSettingsRequest updateSettingsRequest = new ClusterUpdateSettingsRequest();
-        String address = leaderCluster.getDataNodeInstance(TransportService.class).boundAddress().publishAddress().toString();
-        updateSettingsRequest.persistentSettings(Settings.builder().put("cluster.remote.leader_cluster.seeds", address));
-        assertAcked(followerClient().admin().cluster().updateSettings(updateSettingsRequest).actionGet());
     }
 
     /**
@@ -175,7 +170,7 @@ public abstract class CcrIntegTestCase extends ESTestCase {
         }
     }
 
-    private NodeConfigurationSource createNodeConfigurationSource() {
+    private NodeConfigurationSource createNodeConfigurationSource(String leaderSeedAddress) {
         Settings.Builder builder = Settings.builder();
         builder.put(NodeEnvironment.MAX_LOCAL_STORAGE_NODES_SETTING.getKey(), Integer.MAX_VALUE);
         // Default the watermarks to absurdly low to prevent the tests
@@ -195,6 +190,9 @@ public abstract class CcrIntegTestCase extends ESTestCase {
         builder.put(XPackSettings.MACHINE_LEARNING_ENABLED.getKey(), false);
         builder.put(XPackSettings.LOGSTASH_ENABLED.getKey(), false);
         builder.put(LicenseService.SELF_GENERATED_LICENSE_TYPE.getKey(), "trial");
+        if (leaderSeedAddress != null) {
+            builder.put("cluster.remote.leader_cluster.seeds", leaderSeedAddress);
+        }
         return new NodeConfigurationSource() {
             @Override
             public Settings nodeSettings(int nodeOrdinal) {