Add API for resetting state of a SystemIndexPlugin

rest-api-spec/src/main/resources/rest-api-spec/api/features.reset_features.json

@@ -0,0 +1,29 @@
+{
+  "features.reset_features":{
+    "documentation":{
+      "url":"https://www.elastic.co/guide/en/elasticsearch/reference/master/modules-snapshots.html",
+      "description":"Resets the internal state of features, usually by deleting system indices"
+    },
+    "stability":"experimental",
+    "visibility":"public",
+    "headers":{
+      "accept": [ "application/json"]
+    },
+    "url":{
+      "paths":[
+        {
+          "path":"/_features/reset",
+          "methods":[
+            "POST"
+          ]
+        }
+      ]
+    },
+    "params":{
+      "master_timeout":{
+        "type":"time",
+        "description":"Explicit operation timeout for connection to master node"
+      }
+    }
+  }
+}

rest-api-spec/src/main/resources/rest-api-spec/test/features.reset_features/10_basic.yml

@@ -0,0 +1,8 @@
+---
+"Get Features":
+  - skip:
+      features: contains
+      version: " - 7.99.99" # Adjust this after backport
+      reason: "This API was added in 7.13.0"
+  - do: { features.get_features: {}}
+  - contains: {'features': {'name': 'tasks'}}

server/src/internalClusterTest/java/org/elasticsearch/snapshots/FeatureStateResetApiIT.java

@@ -0,0 +1,148 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+package org.elasticsearch.snapshots;
+
+import org.elasticsearch.action.admin.cluster.snapshots.features.ResetFeatureStateAction;
+import org.elasticsearch.action.admin.cluster.snapshots.features.ResetFeatureStateRequest;
+import org.elasticsearch.action.admin.cluster.snapshots.features.ResetFeatureStateResponse;
+import org.elasticsearch.action.admin.indices.get.GetIndexResponse;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.index.IndexNotFoundException;
+import org.elasticsearch.indices.SystemIndexDescriptor;
+import org.elasticsearch.plugins.Plugin;
+import org.elasticsearch.plugins.SystemIndexPlugin;
+import org.elasticsearch.test.ESIntegTestCase;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+
+import static org.hamcrest.Matchers.arrayContaining;
+import static org.hamcrest.Matchers.containsInAnyOrder;
+import static org.hamcrest.Matchers.containsString;
+
+public class FeatureStateResetApiIT extends ESIntegTestCase {
+
+    @Override
+    protected Collection<Class<? extends Plugin>> nodePlugins() {
+        List<Class<? extends Plugin>> plugins = new ArrayList<>(super.nodePlugins());
+        plugins.add(SystemIndexTestPlugin.class);
+        plugins.add(SecondSystemIndexTestPlugin.class);
+        return plugins;
+    }
+
+    /** Check that the reset method cleans up a feature */
+    public void testResetSystemIndices() throws Exception {
+        String systemIndex1 = ".test-system-idx-1";
+        String systemIndex2 = ".second-test-system-idx-1";
+        String associatedIndex = ".associated-idx-1";
+
+        // put a document in a system index
+        indexDoc(systemIndex1, "1", "purpose", "system index doc");
+        refresh(systemIndex1);
+
+        // put a document in a second system index
+        indexDoc(systemIndex2, "1", "purpose", "second system index doc");
+        refresh(systemIndex2);
+
+        // put a document in associated index
+        indexDoc(associatedIndex, "1", "purpose", "associated index doc");
+        refresh(associatedIndex);
+
+        // put a document in a normal index
+        indexDoc("my_index", "1", "purpose", "normal index doc");
+        refresh("my_index");
+
+        // call the reset API
+        ResetFeatureStateResponse apiResponse = client().execute(ResetFeatureStateAction.INSTANCE, new ResetFeatureStateRequest()).get();
+        assertThat(apiResponse.getItemList(), containsInAnyOrder(
+            new ResetFeatureStateResponse.ResetFeatureStateStatus("SystemIndexTestPlugin", "SUCCESS"),
+            new ResetFeatureStateResponse.ResetFeatureStateStatus("SecondSystemIndexTestPlugin", "SUCCESS"),
+            new ResetFeatureStateResponse.ResetFeatureStateStatus("tasks", "SUCCESS")
+        ));
+
+        // verify that both indices are gone
+        Exception e1 = expectThrows(IndexNotFoundException.class, () -> client().admin().indices().prepareGetIndex()
+            .addIndices(systemIndex1)
+            .get());
+
+        assertThat(e1.getMessage(), containsString("no such index"));
+
+        Exception e2 = expectThrows(IndexNotFoundException.class, () -> client().admin().indices().prepareGetIndex()
+            .addIndices(associatedIndex)
+            .get());
+
+        assertThat(e2.getMessage(), containsString("no such index"));
+
+        Exception e3 = expectThrows(IndexNotFoundException.class, () -> client().admin().indices().prepareGetIndex()
+            .addIndices(systemIndex2)
+            .get());
+
+        assertThat(e3.getMessage(), containsString("no such index"));
+
+        GetIndexResponse response = client().admin().indices().prepareGetIndex()
+            .addIndices("my_index")
+            .get();
+
+        assertThat(response.getIndices(), arrayContaining("my_index"));
+    }
+
+    /**
+     * A test plugin with patterns for system indices and associated indices.
+     */
+    public static class SystemIndexTestPlugin extends Plugin implements SystemIndexPlugin {
+
+        public static final String SYSTEM_INDEX_PATTERN = ".test-system-idx*";
+        public static final String ASSOCIATED_INDEX_PATTERN = ".associated-idx*";
+
+        @Override
+        public Collection<SystemIndexDescriptor> getSystemIndexDescriptors(Settings settings) {
+            return Collections.singletonList(new SystemIndexDescriptor(SYSTEM_INDEX_PATTERN, "System indices for tests"));
+        }
+
+        @Override
+        public Collection<String> getAssociatedIndexPatterns() {
+            return Collections.singletonList(ASSOCIATED_INDEX_PATTERN);
+        }
+
+        @Override
+        public String getFeatureName() {
+            return SystemIndexTestPlugin.class.getSimpleName();
+        }
+
+        @Override
+        public String getFeatureDescription() {
+            return "A simple test plugin";
+        }
+    }
+
+    /**
+     * A second test plugin with a patterns for system indices.
+     */
+    public static class SecondSystemIndexTestPlugin extends Plugin implements SystemIndexPlugin {
+
+        public static final String SYSTEM_INDEX_PATTERN = ".second-test-system-idx*";
+
+        @Override
+        public Collection<SystemIndexDescriptor> getSystemIndexDescriptors(Settings settings) {
+            return Collections.singletonList(new SystemIndexDescriptor(SYSTEM_INDEX_PATTERN, "System indices for tests"));
+        }
+
+        @Override
+        public String getFeatureName() {
+            return SecondSystemIndexTestPlugin.class.getSimpleName();
+        }
+
+        @Override
+        public String getFeatureDescription() {
+            return "A second test plugin";
+        }
+    }
+}

server/src/main/java/org/elasticsearch/action/ActionModule.java

@@ -58,7 +58,9 @@
 import org.elasticsearch.action.admin.cluster.snapshots.create.TransportCreateSnapshotAction;
 import org.elasticsearch.action.admin.cluster.snapshots.delete.DeleteSnapshotAction;
 import org.elasticsearch.action.admin.cluster.snapshots.delete.TransportDeleteSnapshotAction;
+import org.elasticsearch.action.admin.cluster.snapshots.features.ResetFeatureStateAction;
 import org.elasticsearch.action.admin.cluster.snapshots.features.SnapshottableFeaturesAction;
+import org.elasticsearch.action.admin.cluster.snapshots.features.TransportResetFeatureStateAction;
 import org.elasticsearch.action.admin.cluster.snapshots.features.TransportSnapshottableFeaturesAction;
 import org.elasticsearch.action.admin.cluster.snapshots.get.GetSnapshotsAction;
 import org.elasticsearch.action.admin.cluster.snapshots.get.TransportGetSnapshotsAction;
@@ -282,6 +284,7 @@
 import org.elasticsearch.rest.action.admin.cluster.RestPutStoredScriptAction;
 import org.elasticsearch.rest.action.admin.cluster.RestReloadSecureSettingsAction;
 import org.elasticsearch.rest.action.admin.cluster.RestRemoteClusterInfoAction;
+import org.elasticsearch.rest.action.admin.cluster.RestResetFeatureStateAction;
 import org.elasticsearch.rest.action.admin.cluster.RestRestoreSnapshotAction;
 import org.elasticsearch.rest.action.admin.cluster.RestSnapshotsStatusAction;
 import org.elasticsearch.rest.action.admin.cluster.RestSnapshottableFeaturesAction;
@@ -501,6 +504,7 @@ public <Request extends ActionRequest, Response extends ActionResponse> void reg
         actions.register(RestoreSnapshotAction.INSTANCE, TransportRestoreSnapshotAction.class);
         actions.register(SnapshotsStatusAction.INSTANCE, TransportSnapshotsStatusAction.class);
         actions.register(SnapshottableFeaturesAction.INSTANCE, TransportSnapshottableFeaturesAction.class);
+        actions.register(ResetFeatureStateAction.INSTANCE, TransportResetFeatureStateAction.class);
 
         actions.register(IndicesStatsAction.INSTANCE, TransportIndicesStatsAction.class);
         actions.register(IndicesSegmentsAction.INSTANCE, TransportIndicesSegmentsAction.class);
@@ -651,6 +655,7 @@ public void initRestHandlers(Supplier<DiscoveryNodes> nodesInCluster) {
         registerHandler.accept(new RestDeleteSnapshotAction());
         registerHandler.accept(new RestSnapshotsStatusAction());
         registerHandler.accept(new RestSnapshottableFeaturesAction());
+        registerHandler.accept(new RestResetFeatureStateAction());
         registerHandler.accept(new RestGetIndicesAction());
         registerHandler.accept(new RestIndicesStatsAction());
         registerHandler.accept(new RestIndicesSegmentsAction(threadPool));

server/src/main/java/org/elasticsearch/action/admin/cluster/snapshots/features/ResetFeatureStateAction.java

@@ -0,0 +1,22 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+package org.elasticsearch.action.admin.cluster.snapshots.features;
+
+import org.elasticsearch.action.ActionType;
+
+/** Action for resetting feature states, mostly meaning system indices */
+public class ResetFeatureStateAction extends ActionType<ResetFeatureStateResponse> {
+
+    public static final ResetFeatureStateAction INSTANCE = new ResetFeatureStateAction();
+    public static final String NAME = "cluster:admin/features/reset";
+
+    private ResetFeatureStateAction() {
+        super(NAME, ResetFeatureStateResponse::new);
+    }
+}

server/src/main/java/org/elasticsearch/action/admin/cluster/snapshots/features/ResetFeatureStateRequest.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+package org.elasticsearch.action.admin.cluster.snapshots.features;
+
+import org.elasticsearch.action.ActionRequest;
+import org.elasticsearch.action.ActionRequestValidationException;
+import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.StreamOutput;
+
+import java.io.IOException;
+
+/** Request for resetting feature state */
+public class ResetFeatureStateRequest extends ActionRequest {
+
+    public ResetFeatureStateRequest() {
+        // TODO[wrb] - We might need to let this request take a list of
+        //  feature state names, but not for the initial implementation
+    }
+
+    public ResetFeatureStateRequest(StreamInput in) throws IOException {
+        super(in);
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        super.writeTo(out);
+    }
+
+    @Override
+    public ActionRequestValidationException validate() {
+        return null;
+    }
+}