Exclude indices with cache disabled from searchable snapshots stats (#52770)

Searchable snapshots stats only make sense for indices 
with the setting SNAPSHOT_CACHE_ENABLED_SETTING 
enabled. This commit prevents non-cached indices to be 
reported in searchable snapshots stats.

Author: tlrx

x-pack/plugin/searchable-snapshots/src/main/java/org/elasticsearch/xpack/searchablesnapshots/action/SearchableSnapshotsStatsResponse.java

@@ -47,6 +47,7 @@ protected void addCustomXContentFields(XContentBuilder builder, Params params) t
             .map(SearchableSnapshotShardStats::getShardRouting)
             .map(ShardRouting::index)
             .sorted(Comparator.comparing(Index::getName))
+            .distinct()
             .collect(toList());
 
         builder.startObject("indices");

x-pack/plugin/searchable-snapshots/src/main/java/org/elasticsearch/xpack/searchablesnapshots/action/TransportSearchableSnapshotsStatsAction.java

@@ -41,6 +41,7 @@
 import java.util.stream.Collectors;
 
 import static org.elasticsearch.index.IndexModule.INDEX_STORE_TYPE_SETTING;
+import static org.elasticsearch.xpack.searchablesnapshots.SearchableSnapshotRepository.SNAPSHOT_CACHE_ENABLED_SETTING;
 import static org.elasticsearch.xpack.searchablesnapshots.SearchableSnapshotRepository.SNAPSHOT_DIRECTORY_FACTORY_KEY;
 
 public class TransportSearchableSnapshotsStatsAction extends TransportBroadcastByNodeAction<SearchableSnapshotsStatsRequest,
@@ -94,7 +95,9 @@ protected ShardsIterator shards(ClusterState state, SearchableSnapshotsStatsRequ
             if (indexMetaData != null) {
                 Settings indexSettings = indexMetaData.getSettings();
                 if (INDEX_STORE_TYPE_SETTING.get(indexSettings).equals(SNAPSHOT_DIRECTORY_FACTORY_KEY)) {
-                    searchableSnapshotIndices.add(concreteIndex);
+                    if (SNAPSHOT_CACHE_ENABLED_SETTING.get(indexSettings)) {
+                        searchableSnapshotIndices.add(concreteIndex);
+                    }
                 }
             }
         }

x-pack/plugin/searchable-snapshots/src/test/java/org/elasticsearch/xpack/searchablesnapshots/AbstractSearchableSnapshotsRestTestCase.java

@@ -6,6 +6,7 @@
 package org.elasticsearch.xpack.searchablesnapshots;
 
 import org.apache.http.client.methods.HttpDelete;
+import org.apache.http.client.methods.HttpGet;
 import org.apache.http.client.methods.HttpPost;
 import org.apache.http.client.methods.HttpPut;
 import org.elasticsearch.action.admin.cluster.repositories.put.PutRepositoryRequest;
@@ -15,6 +16,8 @@
 import org.elasticsearch.client.ResponseException;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
 import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.bytes.BytesReference;
+import org.elasticsearch.common.io.Streams;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.XContentHelper;
 import org.elasticsearch.common.xcontent.XContentType;
@@ -54,9 +57,11 @@ public void testSearchableSnapshots() throws Exception {
             Settings.builder().put("delegate_type", repositoryType).put("readonly", true).put(repositorySettings).build());
 
         final String indexName = randomAlphaOfLength(10).toLowerCase(Locale.ROOT);
+        final int numberOfShards = randomIntBetween(1, 5);
+
         logger.info("creating index [{}]", indexName);
         createIndex(indexName, Settings.builder()
-            .put(IndexMetaData.SETTING_NUMBER_OF_SHARDS, randomIntBetween(1, 5))
+            .put(IndexMetaData.SETTING_NUMBER_OF_SHARDS, numberOfShards)
             .put(IndexMetaData.SETTING_NUMBER_OF_REPLICAS, 0)
             .build());
         ensureGreen(indexName);
@@ -130,6 +135,10 @@ public void testSearchableSnapshots() throws Exception {
 
         logger.info("deleting snapshot [{}]", snapshot);
         deleteSnapshot(repository, snapshot, false);
+
+        final Map<String, Object> searchableSnapshotStats = searchableSnapshotStats(restoredIndexName);
+        assertThat("Expected searchable snapshots stats for " + numberOfShards + " shards but got " + searchableSnapshotStats,
+            searchableSnapshotStats.size(), equalTo(numberOfShards));
     }
 
     protected static void registerRepository(String repository, String type, boolean verify, Settings settings) throws IOException {
@@ -210,11 +219,27 @@ protected static Map<String, Object> search(String index, QueryBuilder query) th
         return responseAsMap;
     }
 
+    protected static Map<String, Object> searchableSnapshotStats(String index) throws IOException {
+        final Response response = client().performRequest(new Request(HttpGet.METHOD_NAME, '/' + index + "/_searchable_snapshots/stats"));
+        assertThat("Failed to retrieve searchable snapshots stats for on index [" + index + "]: " + response,
+            response.getStatusLine().getStatusCode(), equalTo(RestStatus.OK.getStatus()));
+
+        final Map<String, Object> responseAsMap = responseAsMap(response);
+        assertThat("Shard failures when retrieving searchable snapshots stats for index [" + index + "]: " + response,
+            extractValue(responseAsMap, "_shards.failed"), equalTo(0));
+        return extractValue(responseAsMap, "indices." + index + ".shards");
+    }
+
     protected static Map<String, Object> responseAsMap(Response response) throws IOException {
         final XContentType xContentType = XContentType.fromMediaTypeOrFormat(response.getEntity().getContentType().getValue());
         assertThat("Unknown XContentType", xContentType, notNullValue());
-        try (InputStream responseBody = response.getEntity().getContent()) {
+
+        BytesReference bytesReference = Streams.readFully(response.getEntity().getContent());
+
+        try (InputStream responseBody = bytesReference.streamInput()) {
             return XContentHelper.convertToMap(xContentType.xContent(), responseBody, true);
+        } catch (Exception e) {
+            throw new IOException(bytesReference.utf8ToString(), e);
         }
     }
 

x-pack/plugin/searchable-snapshots/src/test/java/org/elasticsearch/xpack/searchablesnapshots/SearchableSnapshotsIntegTests.java

@@ -6,6 +6,8 @@
 package org.elasticsearch.xpack.searchablesnapshots;
 
 import org.apache.lucene.search.TotalHits;
+import org.elasticsearch.ResourceNotFoundException;
+import org.elasticsearch.action.ActionFuture;
 import org.elasticsearch.action.admin.cluster.snapshots.create.CreateSnapshotResponse;
 import org.elasticsearch.action.admin.cluster.snapshots.restore.RestoreSnapshotResponse;
 import org.elasticsearch.action.admin.indices.recovery.RecoveryResponse;
@@ -23,6 +25,10 @@
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.snapshots.SnapshotInfo;
 import org.elasticsearch.test.ESIntegTestCase;
+import org.elasticsearch.xpack.core.searchablesnapshots.SearchableSnapshotShardStats;
+import org.elasticsearch.xpack.searchablesnapshots.action.SearchableSnapshotsStatsAction;
+import org.elasticsearch.xpack.searchablesnapshots.action.SearchableSnapshotsStatsRequest;
+import org.elasticsearch.xpack.searchablesnapshots.action.SearchableSnapshotsStatsResponse;
 import org.elasticsearch.xpack.searchablesnapshots.cache.CacheService;
 
 import java.nio.file.Path;
@@ -39,6 +45,7 @@
 import static org.elasticsearch.xpack.searchablesnapshots.SearchableSnapshotRepository.SNAPSHOT_DIRECTORY_FACTORY_KEY;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.greaterThan;
+import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.lessThanOrEqualTo;
 
 public class SearchableSnapshotsIntegTests extends ESIntegTestCase {
@@ -117,12 +124,15 @@ public void testCreateAndRestoreSearchableSnapshot() throws Exception {
                 .put("location", repo)
                 .put("chunk_size", randomIntBetween(100, 1000), ByteSizeUnit.BYTES)));
 
+        final boolean cacheEnabled = randomBoolean();
+        logger.info("--> restoring index [{}] with cache [{}]", restoredIndexName, cacheEnabled ? "enabled" : "disabled");
+
         final RestoreSnapshotResponse restoreSnapshotResponse = client().admin().cluster()
             .prepareRestoreSnapshot(searchableRepoName, snapshotName).setIndices(indexName)
             .setRenamePattern(indexName)
             .setRenameReplacement(restoredIndexName)
             .setIndexSettings(Settings.builder()
-                .put(SearchableSnapshotRepository.SNAPSHOT_CACHE_ENABLED_SETTING.getKey(), randomBoolean())
+                .put(SearchableSnapshotRepository.SNAPSHOT_CACHE_ENABLED_SETTING.getKey(), cacheEnabled)
                 .put(IndexSettings.INDEX_CHECK_ON_STARTUP.getKey(), Boolean.FALSE.toString())
                 .build())
             .setWaitForCompletion(true).get();
@@ -139,6 +149,19 @@ public void testCreateAndRestoreSearchableSnapshot() throws Exception {
 
         assertRecovered(restoredIndexName, originalAllHits, originalBarHits);
 
+        final SearchableSnapshotsStatsRequest request = new SearchableSnapshotsStatsRequest(restoredIndexName);
+        final ActionFuture<SearchableSnapshotsStatsResponse> future =  client().execute(SearchableSnapshotsStatsAction.INSTANCE, request);
+        if (cacheEnabled) {
+            final SearchableSnapshotsStatsResponse statsResponse = future.actionGet();
+            assertThat(statsResponse.getStats(), hasSize(getNumShards(restoredIndexName).totalNumShards));
+            for (SearchableSnapshotShardStats stats : statsResponse.getStats()) {
+                assertThat(stats.getShardRouting().getIndexName(), equalTo(restoredIndexName));
+                assertThat(stats.getStats().size(), greaterThan(0));
+            }
+        } else {
+            expectThrows(ResourceNotFoundException.class, future::actionGet);
+        }
+
         internalCluster().fullRestart();
         assertRecovered(restoredIndexName, originalAllHits, originalBarHits);