[Remote Store] Add rest endpoint for remote store restore

client/rest-high-level/src/test/java/org/opensearch/client/RestHighLevelClientTests.java

@@ -885,7 +885,8 @@ public void testApiNamingConventions() throws Exception {
             "nodes.hot_threads",
             "nodes.usage",
             "nodes.reload_secure_settings",
-            "search_shards", };
+            "search_shards",
+            "remote_store.restore", };
         List<String> booleanReturnMethods = Arrays.asList("security.enable_user", "security.disable_user", "security.change_password");
         Set<String> deprecatedMethods = new HashSet<>();
         deprecatedMethods.add("indices.force_merge");

rest-api-spec/src/main/resources/rest-api-spec/api/remote_store.restore.json

@@ -0,0 +1,34 @@
+{
+  "remote_store.restore":{
+    "documentation":{
+      "url": "https://opensearch.org/docs/latest/opensearch/rest-api/remote-store#restore",
+      "description":"Restores from remote store."
+    },
+    "stability":"experimental",
+    "url":{
+      "paths":[
+        {
+          "path":"/_remotestore/_restore",
+          "methods":[
+            "POST"
+          ]
+        }
+      ]
+    },
+    "params":{
+      "cluster_manager_timeout":{
+        "type":"time",
+        "description":"Explicit operation timeout for connection to cluster-manager node"
+      },
+      "wait_for_completion":{
+        "type":"boolean",
+        "description":"Should this request wait until the operation has completed before returning",
+        "default":false
+      }
+    },
+    "body":{
+      "description":"A comma separated list of index IDs",
+      "required":true
+    }
+  }
+}

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

@@ -61,6 +61,8 @@
 import org.opensearch.action.admin.cluster.node.usage.TransportNodesUsageAction;
 import org.opensearch.action.admin.cluster.remote.RemoteInfoAction;
 import org.opensearch.action.admin.cluster.remote.TransportRemoteInfoAction;
+import org.opensearch.action.admin.cluster.remotestore.restore.RestoreRemoteStoreAction;
+import org.opensearch.action.admin.cluster.remotestore.restore.TransportRestoreRemoteStoreAction;
 import org.opensearch.action.admin.cluster.repositories.cleanup.CleanupRepositoryAction;
 import org.opensearch.action.admin.cluster.repositories.cleanup.TransportCleanupRepositoryAction;
 import org.opensearch.action.admin.cluster.repositories.delete.DeleteRepositoryAction;
@@ -267,6 +269,7 @@
 import org.opensearch.common.settings.IndexScopedSettings;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.common.settings.SettingsFilter;
+import org.opensearch.common.util.FeatureFlags;
 import org.opensearch.index.seqno.RetentionLeaseActions;
 import org.opensearch.indices.SystemIndices;
 import org.opensearch.indices.breaker.CircuitBreakerService;
@@ -314,6 +317,7 @@
 import org.opensearch.rest.action.admin.cluster.RestPutStoredScriptAction;
 import org.opensearch.rest.action.admin.cluster.RestReloadSecureSettingsAction;
 import org.opensearch.rest.action.admin.cluster.RestRemoteClusterInfoAction;
+import org.opensearch.rest.action.admin.cluster.RestRestoreRemoteStoreAction;
 import org.opensearch.rest.action.admin.cluster.RestRestoreSnapshotAction;
 import org.opensearch.rest.action.admin.cluster.RestSnapshotsStatusAction;
 import org.opensearch.rest.action.admin.cluster.RestVerifyRepositoryAction;
@@ -668,6 +672,9 @@ public <Request extends ActionRequest, Response extends ActionResponse> void reg
         actions.register(GetAllPitsAction.INSTANCE, TransportGetAllPitsAction.class);
         actions.register(DeletePitAction.INSTANCE, TransportDeletePitAction.class);
 
+        // Remote Store
+        actions.register(RestoreRemoteStoreAction.INSTANCE, TransportRestoreRemoteStoreAction.class);
+
         return unmodifiableMap(actions.getRegistry());
     }
 
@@ -853,6 +860,11 @@ public void initRestHandlers(Supplier<DiscoveryNodes> nodesInCluster) {
             }
         }
         registerHandler.accept(new RestCatAction(catActions));
+
+        // Remote Store APIs
+        if (FeatureFlags.isEnabled(FeatureFlags.REMOTE_STORE)) {
+            registerHandler.accept(new RestRestoreRemoteStoreAction());
+        }
     }
 
     @Override

server/src/main/java/org/opensearch/action/admin/cluster/remotestore/restore/RestoreRemoteStoreAction.java

@@ -0,0 +1,26 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.action.admin.cluster.remotestore.restore;
+
+import org.opensearch.action.ActionType;
+
+/**
+ * Restore remote store action
+ *
+ * @opensearch.internal
+ */
+public final class RestoreRemoteStoreAction extends ActionType<RestoreRemoteStoreResponse> {
+
+    public static final RestoreRemoteStoreAction INSTANCE = new RestoreRemoteStoreAction();
+    public static final String NAME = "cluster:admin/remotestore/restore";
+
+    private RestoreRemoteStoreAction() {
+        super(NAME, RestoreRemoteStoreResponse::new);
+    }
+}

server/src/main/java/org/opensearch/action/admin/cluster/remotestore/restore/RestoreRemoteStoreResponse.java

@@ -0,0 +1,126 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.action.admin.cluster.remotestore.restore;
+
+import org.opensearch.action.ActionResponse;
+import org.opensearch.common.Nullable;
+import org.opensearch.common.ParseField;
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+import org.opensearch.common.xcontent.ConstructingObjectParser;
+import org.opensearch.common.xcontent.ToXContentObject;
+import org.opensearch.common.xcontent.XContentBuilder;
+import org.opensearch.common.xcontent.XContentParser;
+import org.opensearch.rest.RestStatus;
+import org.opensearch.snapshots.RestoreInfo;
+
+import java.io.IOException;
+import java.util.Objects;
+
+import static org.opensearch.common.xcontent.ConstructingObjectParser.optionalConstructorArg;
+
+/**
+ * Contains information about remote store restores
+ *
+ * @opensearch.internal
+ */
+public final class RestoreRemoteStoreResponse extends ActionResponse implements ToXContentObject {
+
+    @Nullable
+    private final RestoreInfo restoreInfo;
+
+    public RestoreRemoteStoreResponse(@Nullable RestoreInfo restoreInfo) {
+        this.restoreInfo = restoreInfo;
+    }
+
+    public RestoreRemoteStoreResponse(StreamInput in) throws IOException {
+        super(in);
+        restoreInfo = RestoreInfo.readOptionalRestoreInfo(in);
+    }
+
+    /**
+     * Returns restore information if remote store restore was completed before this method returned, null otherwise
+     *
+     * @return restore information or null
+     */
+    public RestoreInfo getRestoreInfo() {
+        return restoreInfo;
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        out.writeOptionalWriteable(restoreInfo);
+    }
+
+    public RestStatus status() {
+        if (restoreInfo == null) {
+            return RestStatus.ACCEPTED;
+        }
+        return restoreInfo.status();
+    }
+
+    @Override
+    public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+        builder.startObject();
+        if (restoreInfo != null) {
+            builder.field("remote_store");
+            restoreInfo.toXContent(builder, params);
+        } else {
+            builder.field("accepted", true);
+        }
+        builder.endObject();
+        return builder;
+    }
+
+    public static final ConstructingObjectParser<RestoreRemoteStoreResponse, Void> PARSER = new ConstructingObjectParser<>(
+        "restore_remote_store",
+        true,
+        v -> {
+            RestoreInfo restoreInfo = (RestoreInfo) v[0];
+            Boolean accepted = (Boolean) v[1];
+            assert (accepted == null && restoreInfo != null) || (accepted != null && accepted && restoreInfo == null) : "accepted: ["
+                + accepted
+                + "], restoreInfo: ["
+                + restoreInfo
+                + "]";
+            return new RestoreRemoteStoreResponse(restoreInfo);
+        }
+    );
+
+    static {
+        PARSER.declareObject(
+            optionalConstructorArg(),
+            (parser, context) -> RestoreInfo.fromXContent(parser),
+            new ParseField("remote_store")
+        );
+        PARSER.declareBoolean(optionalConstructorArg(), new ParseField("accepted"));
+    }
+
+    public static RestoreRemoteStoreResponse fromXContent(XContentParser parser) throws IOException {
+        return PARSER.parse(parser, null);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        RestoreRemoteStoreResponse that = (RestoreRemoteStoreResponse) o;
+        return Objects.equals(restoreInfo, that.restoreInfo);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(restoreInfo);
+    }
+
+    @Override
+    public String toString() {
+        return "RestoreRemoteStoreResponse{" + "restoreInfo=" + restoreInfo + '}';
+    }
+}

server/src/main/java/org/opensearch/action/admin/cluster/remotestore/restore/TransportRestoreRemoteStoreAction.java

@@ -0,0 +1,103 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.action.admin.cluster.remotestore.restore;
+
+import org.opensearch.action.ActionListener;
+import org.opensearch.action.admin.cluster.snapshots.restore.RestoreClusterStateListener;
+import org.opensearch.action.support.ActionFilters;
+import org.opensearch.action.support.clustermanager.TransportClusterManagerNodeAction;
+import org.opensearch.cluster.ClusterState;
+import org.opensearch.cluster.block.ClusterBlockException;
+import org.opensearch.cluster.block.ClusterBlockLevel;
+import org.opensearch.cluster.metadata.IndexNameExpressionResolver;
+import org.opensearch.cluster.service.ClusterService;
+import org.opensearch.common.inject.Inject;
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.snapshots.RestoreService;
+import org.opensearch.threadpool.ThreadPool;
+import org.opensearch.transport.TransportService;
+
+import java.io.IOException;
+
+/**
+ * Transport action for restore remote store operation
+ *
+ * @opensearch.internal
+ */
+public final class TransportRestoreRemoteStoreAction extends TransportClusterManagerNodeAction<
+    RestoreRemoteStoreRequest,
+    RestoreRemoteStoreResponse> {
+    private final RestoreService restoreService;
+
+    @Inject
+    public TransportRestoreRemoteStoreAction(
+        TransportService transportService,
+        ClusterService clusterService,
+        ThreadPool threadPool,
+        RestoreService restoreService,
+        ActionFilters actionFilters,
+        IndexNameExpressionResolver indexNameExpressionResolver
+    ) {
+        super(
+            RestoreRemoteStoreAction.NAME,
+            transportService,
+            clusterService,
+            threadPool,
+            actionFilters,
+            RestoreRemoteStoreRequest::new,
+            indexNameExpressionResolver
+        );
+        this.restoreService = restoreService;
+    }
+
+    @Override
+    protected String executor() {
+        return ThreadPool.Names.GENERIC;
+    }
+
+    @Override
+    protected RestoreRemoteStoreResponse read(StreamInput in) throws IOException {
+        return new RestoreRemoteStoreResponse(in);
+    }
+
+    @Override
+    protected ClusterBlockException checkBlock(RestoreRemoteStoreRequest request, ClusterState state) {
+        // Restoring a remote store might change the global state and create/change an index,
+        // so we need to check for METADATA_WRITE and WRITE blocks
+        ClusterBlockException blockException = state.blocks().globalBlockedException(ClusterBlockLevel.METADATA_WRITE);
+        if (blockException != null) {
+            return blockException;
+        }
+        return state.blocks().globalBlockedException(ClusterBlockLevel.WRITE);
+
+    }
+
+    @Override
+    protected void clusterManagerOperation(
+        final RestoreRemoteStoreRequest request,
+        final ClusterState state,
+        final ActionListener<RestoreRemoteStoreResponse> listener
+    ) {
+        restoreService.restoreFromRemoteStore(
+            request,
+            ActionListener.delegateFailure(listener, (delegatedListener, restoreCompletionResponse) -> {
+                if (restoreCompletionResponse.getRestoreInfo() == null && request.waitForCompletion()) {
+                    RestoreClusterStateListener.createAndRegisterListener(
+                        clusterService,
+                        restoreCompletionResponse,
+                        delegatedListener,
+                        RestoreRemoteStoreResponse::new
+                    );
+                } else {
+                    delegatedListener.onResponse(new RestoreRemoteStoreResponse(restoreCompletionResponse.getRestoreInfo()));
+                }
+            })
+        );
+    }
+}

server/src/main/java/org/opensearch/action/admin/cluster/remotestore/restore/package-info.java

@@ -6,5 +6,5 @@
  * compatible open source license.
  */
 
-/** Restore Snapshot transport handler. */
+/** Restore remote store transport handler. */
 package org.opensearch.action.admin.cluster.remotestore.restore;