Add API for clearing file cache on search nodes

CHANGELOG.md

@@ -83,6 +83,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 ### Added
 - [Extensions] Moving Extensions APIs to protobuf serialization. ([#6960](https:/opensearch-project/OpenSearch/pull/6960))
 - Add descending order search optimization through reverse segment read. ([#7244](https:/opensearch-project/OpenSearch/pull/7244))
+- API to clear filecache on search capable nodes ([#7323](https:/opensearch-project/OpenSearch/pull/7323))
 
 ### Dependencies
 - Bump `jackson` from 2.14.2 to 2.15.0 ([#7286](https:/opensearch-project/OpenSearch/pull/7286)
@@ -99,4 +100,4 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 ### Security
 
 [Unreleased 3.0]: https:/opensearch-project/OpenSearch/compare/2.x...HEAD
-[Unreleased 2.x]: https:/opensearch-project/OpenSearch/compare/2.5...2.x
+[Unreleased 2.x]: https:/opensearch-project/OpenSearch/compare/2.5...2.x

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

@@ -870,6 +870,7 @@ public void testApiNamingConventions() throws Exception {
  "ingest.processor_grok",
  "nodes.info",
  "nodes.stats",
+ "nodes.clear_filecache",
  "nodes.hot_threads",
  "nodes.usage",
  "nodes.reload_secure_settings",

rest-api-spec/src/main/resources/rest-api-spec/api/nodes.clear_filecache.json

@@ -0,0 +1,19 @@
+{
+ "nodes.clear_filecache":{
+ "documentation":{
+ "url": "https://opensearch.org/docs/latest/opensearch/rest-api/filecache#clear",
+ "description":"Clears all file caches for one or more search capable nodes."
+ },
+ "stability":"experimental",
+ "url":{
+ "paths":[
+ {
+ "path":"/_filecache/clear",
+ "methods":[
+ "POST"
+ ]
+ }
+ ]
+ }
+ }
+}

server/src/internalClusterTest/java/org/opensearch/snapshots/SearchableSnapshotIT.java

@@ -7,6 +7,9 @@
 import com.carrotsearch.randomizedtesting.annotations.ThreadLeakFilters;
 import com.carrotsearch.randomizedtesting.generators.RandomPicks;
 import org.hamcrest.MatcherAssert;
+import org.opensearch.action.admin.cluster.node.filecache.clear.ClearNodeFileCacheResponse;
+import org.opensearch.action.admin.cluster.node.filecache.clear.ClearNodesFileCacheRequest;
+import org.opensearch.action.admin.cluster.node.filecache.clear.ClearNodesFileCacheResponse;
 import org.opensearch.action.admin.cluster.node.stats.NodeStats;
 import org.opensearch.action.admin.cluster.node.stats.NodesStatsRequest;
 import org.opensearch.action.admin.cluster.node.stats.NodesStatsResponse;
@@ -664,6 +667,41 @@ public void testCacheIndexFilesClearedOnDelete() throws Exception {
  logger.info("--> validated that the cache file path doesn't exist");
  }
 
+ /**
+ * Test scenario that calls the clear filecache API which prunes the file cache
+ * Ensures that the filecache was pruned on all the search capable nodes.
+ */
+ public void testFileCacheClearAPI() throws Exception {
+ final int numReplicas = randomIntBetween(1, 4);
+ final int numShards = numReplicas + 1;
+ final String indexName = "test-idx";
+ final String restoredIndexName = indexName + "-copy";
+ final String repoName = "test-repo";
+ final String snapshotName = "test-snap";
+ final Client client = client();
+
+ internalCluster().ensureAtLeastNumSearchAndDataNodes(numShards);
+ createIndexWithDocsAndEnsureGreen(numReplicas, 100, indexName);
+ createRepositoryWithSettings(null, repoName);
+ takeSnapshot(client, snapshotName, repoName, indexName);
+ restoreSnapshotAndEnsureGreen(client, snapshotName, repoName);
+ assertDocCount(restoredIndexName, 100L);
+ assertRemoteSnapshotIndexSettings(client, restoredIndexName);
+
+ ClearNodesFileCacheResponse nodesResponse = client.admin().cluster().clearFileCache(new ClearNodesFileCacheRequest()).actionGet();
+ int nodesClearedCount = 0;
+ for (ClearNodeFileCacheResponse nodeResponse : nodesResponse.getNodes()) {
+ if (nodeResponse.getNode().isSearchNode()) {
+ nodesClearedCount++;
+ assertTrue(nodeResponse.isCleared());
+ assertTrue(nodeResponse.getCount() >= 0);
+ }
+ }
+
+ assertEquals(nodesClearedCount, numShards);
+ deleteIndicesAndEnsureGreen(client, restoredIndexName);
+ }
+
  /**
  * Asserts the cache folder count to match the number of shards and the number of indices within the cache folder
  * as provided.

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

@@ -149,6 +149,8 @@
 import org.opensearch.action.admin.indices.delete.TransportDeleteIndexAction;
 import org.opensearch.action.admin.indices.exists.indices.IndicesExistsAction;
 import org.opensearch.action.admin.indices.exists.indices.TransportIndicesExistsAction;
+import org.opensearch.action.admin.cluster.node.filecache.clear.ClearNodesFileCacheAction;
+import org.opensearch.action.admin.cluster.node.filecache.clear.TransportClearNodesFileCacheAction;
 import org.opensearch.action.admin.indices.flush.FlushAction;
 import org.opensearch.action.admin.indices.flush.TransportFlushAction;
 import org.opensearch.action.admin.indices.forcemerge.ForceMergeAction;
@@ -311,6 +313,7 @@
 import org.opensearch.rest.action.admin.cluster.RestAddVotingConfigExclusionAction;
 import org.opensearch.rest.action.admin.cluster.RestCancelTasksAction;
 import org.opensearch.rest.action.admin.cluster.RestCleanupRepositoryAction;
+import org.opensearch.rest.action.admin.cluster.RestClearNodesFileCacheAction;
 import org.opensearch.rest.action.admin.cluster.RestClearVotingConfigExclusionsAction;
 import org.opensearch.rest.action.admin.cluster.RestCloneSnapshotAction;
 import org.opensearch.rest.action.admin.cluster.RestClusterAllocationExplainAction;
@@ -580,6 +583,7 @@ public <Request extends ActionRequest, Response extends ActionResponse> void reg
  actions.register(NodesInfoAction.INSTANCE, TransportNodesInfoAction.class);
  actions.register(RemoteInfoAction.INSTANCE, TransportRemoteInfoAction.class);
  actions.register(NodesStatsAction.INSTANCE, TransportNodesStatsAction.class);
+ actions.register(ClearNodesFileCacheAction.INSTANCE, TransportClearNodesFileCacheAction.class);
  actions.register(NodesUsageAction.INSTANCE, TransportNodesUsageAction.class);
  actions.register(NodesHotThreadsAction.INSTANCE, TransportNodesHotThreadsAction.class);
  actions.register(ListTasksAction.INSTANCE, TransportListTasksAction.class);
@@ -769,6 +773,7 @@ public void initRestHandlers(Supplier<DiscoveryNodes> nodesInCluster) {
  registerHandler.accept(new RestNodesInfoAction(settingsFilter));
  registerHandler.accept(new RestRemoteClusterInfoAction());
  registerHandler.accept(new RestNodesStatsAction());
+ registerHandler.accept(new RestClearNodesFileCacheAction());
  registerHandler.accept(new RestNodesUsageAction());
  registerHandler.accept(new RestNodesHotThreadsAction());
  registerHandler.accept(new RestClusterAllocationExplainAction());

server/src/main/java/org/opensearch/action/admin/cluster/node/filecache/clear/ClearNodeFileCacheResponse.java

@@ -0,0 +1,73 @@
+/*
+ * 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.node.filecache.clear;
+
+import org.opensearch.action.support.nodes.BaseNodeResponse;
+import org.opensearch.cluster.node.DiscoveryNode;
+import org.opensearch.cluster.node.DiscoveryNodeRole;
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+import org.opensearch.core.xcontent.ToXContentFragment;
+import org.opensearch.core.xcontent.XContentBuilder;
+
+import java.io.IOException;
+
+/**
+ * The response of a clear filecache action for a single node.
+ *
+ * @opensearch.internal
+ */
+public class ClearNodeFileCacheResponse extends BaseNodeResponse implements ToXContentFragment {
+
+ boolean cleared;
+
+ long count;
+
+ protected ClearNodeFileCacheResponse(StreamInput in) throws IOException {
+ super(in);
+ cleared = in.readBoolean();
+ count = in.readLong();
+ }
+
+ public ClearNodeFileCacheResponse(DiscoveryNode discoveryNode, boolean cleared, long count) {
+ super(discoveryNode);
+ this.cleared = cleared;
+ this.count = count;
+ }
+
+ public boolean isCleared() {
+ return cleared;
+ }
+
+ public long getCount() {
+ return count;
+ }
+
+ @Override
+ public void writeTo(StreamOutput out) throws IOException {
+ super.writeTo(out);
+ out.writeBoolean(cleared);
+ out.writeLong(count);
+ }
+
+ @Override
+ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+ builder.field("name", getNode().getName());
+
+ builder.startArray("roles");
+ for (DiscoveryNodeRole role : getNode().getRoles()) {
+ builder.value(role.roleName());
+ }
+ builder.endArray();
+
+ builder.field("cleared", cleared);
+ builder.field("item_count", count);
+ return builder;
+ }
+}

server/src/main/java/org/opensearch/action/admin/cluster/node/filecache/clear/ClearNodesFileCacheAction.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.node.filecache.clear;
+
+import org.opensearch.action.ActionType;
+
+/**
+ * Transport action for clearing filecache on nodes
+ *
+ * @opensearch.internal
+ */
+public class ClearNodesFileCacheAction extends ActionType<ClearNodesFileCacheResponse> {
+
+ public static final ClearNodesFileCacheAction INSTANCE = new ClearNodesFileCacheAction();
+ public static final String NAME = "cluster:admin/nodes/filecache/clear";
+
+ private ClearNodesFileCacheAction() {
+ super(NAME, ClearNodesFileCacheResponse::new);
+ }
+}

server/src/main/java/org/opensearch/action/admin/cluster/node/filecache/clear/ClearNodesFileCacheRequest.java

@@ -0,0 +1,36 @@
+/*
+ * 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.node.filecache.clear;
+
+import org.opensearch.action.support.nodes.BaseNodesRequest;
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+
+import java.io.IOException;
+
+/**
+ * Request object for clearing filecache on nodes
+ *
+ * @opensearch.internal
+ */
+public class ClearNodesFileCacheRequest extends BaseNodesRequest<ClearNodesFileCacheRequest> {
+
+ public ClearNodesFileCacheRequest() {
+ super((String[]) null);
+ }
+
+ public ClearNodesFileCacheRequest(StreamInput in) throws IOException {
+ super(in);
+ }
+
+ @Override
+ public void writeTo(StreamOutput out) throws IOException {
+ super.writeTo(out);
+ }
+}

server/src/main/java/org/opensearch/action/admin/cluster/node/filecache/clear/ClearNodesFileCacheResponse.java

@@ -0,0 +1,63 @@
+/*
+ * 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.node.filecache.clear;
+
+import org.opensearch.action.FailedNodeException;
+import org.opensearch.action.support.nodes.BaseNodesResponse;
+import org.opensearch.cluster.ClusterName;
+import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.common.io.stream.StreamOutput;
+import org.opensearch.core.xcontent.ToXContentFragment;
+import org.opensearch.core.xcontent.XContentBuilder;
+
+import java.io.IOException;
+import java.util.List;
+
+/**
+ * The response of a clear filecache action aggregated across nodes.
+ *
+ * @opensearch.internal
+ */
+public class ClearNodesFileCacheResponse extends BaseNodesResponse<ClearNodeFileCacheResponse> implements ToXContentFragment {
+
+ ClearNodesFileCacheResponse(StreamInput in) throws IOException {
+ super(in);
+ }
+
+ ClearNodesFileCacheResponse(
+ ClusterName clusterName,
+ List<ClearNodeFileCacheResponse> clearNodeFileCachResponses,
+ List<FailedNodeException> failures
+ ) {
+ super(clusterName, clearNodeFileCachResponses, failures);
+ }
+
+ @Override
+ protected List<ClearNodeFileCacheResponse> readNodesFrom(StreamInput in) throws IOException {
+ return in.readList(ClearNodeFileCacheResponse::new);
+ }
+
+ @Override
+ protected void writeNodesTo(StreamOutput out, List<ClearNodeFileCacheResponse> clearNodeFileCacheResponse) throws IOException {
+ out.writeList(clearNodeFileCacheResponse);
+ }
+
+ @Override
+ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+ builder.startObject("nodes");
+ for (ClearNodeFileCacheResponse clearNodeFileCacheResponse : getNodes()) {
+ builder.startObject(clearNodeFileCacheResponse.getNode().getId());
+ clearNodeFileCacheResponse.toXContent(builder, params);
+ builder.endObject();
+ }
+ builder.endObject();
+
+ return builder;
+ }
+}