ILM open/close steps are noop if idx is open/close (#48614)

The open and close follower steps didn't check if the index is open,
closed respectively, before executing the open/close request.
This changes the steps to check the index state and only perform the
open/close operation if the index is not already open/closed.

Author: andreidan

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ilm/CloseFollowerIndexStep.java

@@ -32,13 +32,17 @@ void performDuringNoSnapshot(IndexMetaData indexMetaData, ClusterState currentCl
             return;
         }
 
-        CloseIndexRequest closeIndexRequest = new CloseIndexRequest(followerIndex);
-        getClient().admin().indices().close(closeIndexRequest, ActionListener.wrap(
-            r -> {
-                assert r.isAcknowledged() : "close index response is not acknowledged";
-                listener.onResponse(true);
-            },
-            listener::onFailure)
-        );
+        if (indexMetaData.getState() == IndexMetaData.State.OPEN) {
+            CloseIndexRequest closeIndexRequest = new CloseIndexRequest(followerIndex);
+            getClient().admin().indices().close(closeIndexRequest, ActionListener.wrap(
+                r -> {
+                    assert r.isAcknowledged() : "close index response is not acknowledged";
+                    listener.onResponse(true);
+                },
+                listener::onFailure)
+            );
+        } else {
+            listener.onResponse(true);
+        }
     }
 }

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ilm/OpenFollowerIndexStep.java

@@ -23,13 +23,17 @@ final class OpenFollowerIndexStep extends AsyncActionStep {
     @Override
     public void performAction(IndexMetaData indexMetaData, ClusterState currentClusterState,
                               ClusterStateObserver observer, Listener listener) {
-        OpenIndexRequest request = new OpenIndexRequest(indexMetaData.getIndex().getName());
-        getClient().admin().indices().open(request, ActionListener.wrap(
-            r -> {
-                assert r.isAcknowledged() :  "open index response is not acknowledged";
-                listener.onResponse(true);
-            },
-            listener::onFailure
-        ));
+        if (indexMetaData.getState() == IndexMetaData.State.CLOSE) {
+            OpenIndexRequest request = new OpenIndexRequest(indexMetaData.getIndex().getName());
+            getClient().admin().indices().open(request, ActionListener.wrap(
+                r -> {
+                    assert r.isAcknowledged() : "open index response is not acknowledged";
+                    listener.onResponse(true);
+                },
+                listener::onFailure
+            ));
+        } else {
+            listener.onResponse(true);
+        }
     }
 }

x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/ilm/CloseFollowerIndexStepTests.java

@@ -110,6 +110,30 @@ public void onFailure(Exception e) {
         Mockito.verifyNoMoreInteractions(indicesClient);
     }
 
+    public void testCloseFollowerIndexIsNoopForAlreadyClosedIndex() {
+        IndexMetaData indexMetadata = IndexMetaData.builder("follower-index")
+            .settings(settings(Version.CURRENT).put(LifecycleSettings.LIFECYCLE_INDEXING_COMPLETE, "true"))
+            .putCustom(CCR_METADATA_KEY, Collections.emptyMap())
+            .state(IndexMetaData.State.CLOSE)
+            .numberOfShards(1)
+            .numberOfReplicas(0)
+            .build();
+        Client client = Mockito.mock(Client.class);
+        CloseFollowerIndexStep step = new CloseFollowerIndexStep(randomStepKey(), randomStepKey(), client);
+        step.performAction(indexMetadata, null, null, new AsyncActionStep.Listener() {
+            @Override
+            public void onResponse(boolean complete) {
+                assertThat(complete, is(true));
+            }
+
+            @Override
+            public void onFailure(Exception e) {
+            }
+        });
+
+        Mockito.verifyZeroInteractions(client);
+    }
+
     @Override
     protected CloseFollowerIndexStep createRandomInstance() {
         Step.StepKey stepKey = randomStepKey();

x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/ilm/OpenFollowerIndexStepTests.java

@@ -51,10 +51,35 @@ protected OpenFollowerIndexStep copyInstance(OpenFollowerIndexStep instance) {
         return new OpenFollowerIndexStep(instance.getKey(), instance.getNextStepKey(), instance.getClient());
     }
 
+    public void testOpenFollowerIndexIsNoopForAlreadyOpenIndex() {
+        IndexMetaData indexMetadata = IndexMetaData.builder("follower-index")
+            .settings(settings(Version.CURRENT).put(LifecycleSettings.LIFECYCLE_INDEXING_COMPLETE, "true"))
+            .putCustom(CCR_METADATA_KEY, Collections.emptyMap())
+            .state(IndexMetaData.State.OPEN)
+            .numberOfShards(1)
+            .numberOfReplicas(0)
+            .build();
+        Client client = Mockito.mock(Client.class);
+        OpenFollowerIndexStep step = new OpenFollowerIndexStep(randomStepKey(), randomStepKey(), client);
+        step.performAction(indexMetadata, null, null, new AsyncActionStep.Listener() {
+            @Override
+            public void onResponse(boolean complete) {
+                assertThat(complete, is(true));
+            }
+
+            @Override
+            public void onFailure(Exception e) {
+            }
+        });
+
+        Mockito.verifyZeroInteractions(client);
+    }
+
     public void testOpenFollowingIndex() {
         IndexMetaData indexMetadata = IndexMetaData.builder("follower-index")
             .settings(settings(Version.CURRENT).put(LifecycleSettings.LIFECYCLE_INDEXING_COMPLETE, "true"))
             .putCustom(CCR_METADATA_KEY, Collections.emptyMap())
+            .state(IndexMetaData.State.CLOSE)
             .numberOfShards(1)
             .numberOfReplicas(0)
             .build();
@@ -95,6 +120,7 @@ public void onFailure(Exception e) {
     public void testOpenFollowingIndexFailed() {
         IndexMetaData indexMetadata = IndexMetaData.builder("follower-index")
             .settings(settings(Version.CURRENT).put(LifecycleSettings.LIFECYCLE_INDEXING_COMPLETE, "true"))
+            .state(IndexMetaData.State.CLOSE)
             .putCustom(CCR_METADATA_KEY, Collections.emptyMap())
             .numberOfShards(1)
             .numberOfReplicas(0)