Using generic enumMap for holding phase stats

server/src/internalClusterTest/java/org/opensearch/search/SearchWeightedRoutingIT.java

@@ -189,21 +189,24 @@ public void testSearchWithWRRShardRouting() throws IOException {
 
         for (NodeStats stat : nodeStats.getNodes()) {
             SearchStats.Stats searchStats = stat.getIndices().getSearch().getTotal();
-            if (searchStats.getRequestStatsLongHolder().getSearchPhaseMetricMap().get(SearchPhaseName.QUERY.getName()) > 0) {
+            if (searchStats.getRequestStatsLongHolder()
+                .getRequestStatsHolder()
+                .get(SearchPhaseName.QUERY.getName())
+                .getTimeInMillis() > 0) {
                 assertThat(
-                    searchStats.getRequestStatsLongHolder().getSearchPhaseTotalMap().get(SearchPhaseName.QUERY.getName()).longValue(),
+                    searchStats.getRequestStatsLongHolder().getRequestStatsHolder().get(SearchPhaseName.QUERY.getName()).getTotal(),
                     greaterThan(0L)
                 );
                 assertThat(
-                    searchStats.getRequestStatsLongHolder().getSearchPhaseMetricMap().get(SearchPhaseName.FETCH.getName()).longValue(),
+                    searchStats.getRequestStatsLongHolder().getRequestStatsHolder().get(SearchPhaseName.FETCH.getName()).getTimeInMillis(),
                     greaterThan(0L)
                 );
                 assertThat(
-                    searchStats.getRequestStatsLongHolder().getSearchPhaseTotalMap().get(SearchPhaseName.FETCH.getName()).longValue(),
+                    searchStats.getRequestStatsLongHolder().getRequestStatsHolder().get(SearchPhaseName.FETCH.getName()).getTotal(),
                     greaterThan(0L)
                 );
                 assertThat(
-                    searchStats.getRequestStatsLongHolder().getSearchPhaseTotalMap().get(SearchPhaseName.EXPAND.getName()).longValue(),
+                    searchStats.getRequestStatsLongHolder().getRequestStatsHolder().get(SearchPhaseName.EXPAND.getName()).getTotal(),
                     greaterThan(0L)
                 );
                 coordNumber += 1;

server/src/internalClusterTest/java/org/opensearch/search/stats/SearchStatsIT.java

@@ -199,22 +199,22 @@ public void testSimpleStats() throws Exception {
 
         for (NodeStats stat : nodeStats.getNodes()) {
             Stats total = stat.getIndices().getSearch().getTotal();
-            if (total.getRequestStatsLongHolder().getSearchPhaseMetricMap().get(SearchPhaseName.QUERY.getName()) > 0) {
-                assertEquals(
-                    iters,
-                    total.getRequestStatsLongHolder().getSearchPhaseTotalMap().get(SearchPhaseName.QUERY.getName()).intValue()
-                );
+            if (total.getRequestStatsLongHolder().getRequestStatsHolder().get(SearchPhaseName.QUERY.getName()).getTimeInMillis() > 0) {
                 assertThat(
-                    total.getRequestStatsLongHolder().getSearchPhaseMetricMap().get(SearchPhaseName.FETCH.getName()),
+                    total.getRequestStatsLongHolder().getRequestStatsHolder().get(SearchPhaseName.FETCH.getName()).getTimeInMillis(),
                     greaterThan(0L)
                 );
                 assertEquals(
                     iters,
-                    total.getRequestStatsLongHolder().getSearchPhaseTotalMap().get(SearchPhaseName.FETCH.getName()).intValue()
+                    total.getRequestStatsLongHolder().getRequestStatsHolder().get(SearchPhaseName.FETCH.getName()).getTotal()
+                );
+                assertEquals(
+                    iters,
+                    total.getRequestStatsLongHolder().getRequestStatsHolder().get(SearchPhaseName.EXPAND.getName()).getTotal()
                 );
                 assertEquals(
                     iters,
-                    total.getRequestStatsLongHolder().getSearchPhaseTotalMap().get(SearchPhaseName.EXPAND.getName()).intValue()
+                    total.getRequestStatsLongHolder().getRequestStatsHolder().get(SearchPhaseName.FETCH.getName()).getTotal()
                 );
                 numOfCoordinators += 1;
             }

server/src/main/java/org/opensearch/action/admin/indices/stats/CommonStats.java

@@ -33,7 +33,6 @@
 package org.opensearch.action.admin.indices.stats;
 
 import org.apache.lucene.store.AlreadyClosedException;
-import org.opensearch.action.RequestStats;
 import org.opensearch.common.Nullable;
 import org.opensearch.core.common.io.stream.StreamInput;
 import org.opensearch.core.common.io.stream.StreamOutput;
@@ -285,14 +284,6 @@ public void writeTo(StreamOutput out) throws IOException {
         out.writeOptionalWriteable(recoveryStats);
     }
 
-    // We are adding request stats with a separate setter method since SearchStats was tightly coupled with Shard Search Stats, and all
-    // nodes won't share the same response in requestStats
-    public void addRequestStats(RequestStats requestStats) {
-        if (requestStats.getSearchRequestStats() != null && this.search != null) {
-            search.setSearchRequestStats(requestStats.getSearchRequestStats());
-        }
-    }
-
     public void add(CommonStats stats) {
         if (docs == null) {
             if (stats.getDocs() != null) {

server/src/main/java/org/opensearch/action/search/AbstractSearchAsyncAction.java

@@ -50,7 +50,6 @@
 import org.opensearch.common.util.concurrent.AtomicArray;
 import org.opensearch.core.action.ActionListener;
 import org.opensearch.core.action.ShardOperationFailedException;
-import org.opensearch.core.common.util.CollectionUtils;
 import org.opensearch.core.index.shard.ShardId;
 import org.opensearch.search.SearchPhaseResult;
 import org.opensearch.search.SearchShardTarget;
@@ -66,6 +65,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.Executor;
@@ -120,8 +120,7 @@ abstract class AbstractSearchAsyncAction<Result extends SearchPhaseResult> exten
 
     private final List<Releasable> releasables = new ArrayList<>();
 
-    private SearchRequestOperationsListener searchRequestOperationsListener;
-    private List<SearchRequestOperationsListener> searchListenersList;
+    private Optional<SearchRequestOperationsListener> searchRequestOperationsListener;
 
     AbstractSearchAsyncAction(
         String name,
@@ -141,7 +140,7 @@ abstract class AbstractSearchAsyncAction<Result extends SearchPhaseResult> exten
         SearchPhaseResults<Result> resultConsumer,
         int maxConcurrentRequestsPerNode,
         SearchResponse.Clusters clusters,
-        List<SearchRequestOperationsListener> searchListenersList
+        SearchRequestOperationsListener searchRequestOperationsListener
     ) {
         super(name);
         final List<SearchShardIterator> toSkipIterators = new ArrayList<>();
@@ -177,10 +176,7 @@ abstract class AbstractSearchAsyncAction<Result extends SearchPhaseResult> exten
         this.indexRoutings = indexRoutings;
         this.results = resultConsumer;
         this.clusters = clusters;
-        if (!CollectionUtils.isEmpty(searchListenersList)) {
-            this.searchListenersList = searchListenersList;
-            this.searchRequestOperationsListener = new SearchRequestOperationsListener.CompositeListener(this.searchListenersList, logger);
-        }
+        this.searchRequestOperationsListener = Optional.ofNullable(searchRequestOperationsListener);
     }
 
     @Override
@@ -436,16 +432,12 @@ public final void executeNextPhase(SearchPhase currentPhase, SearchPhase nextPha
     }
 
     private void onPhaseEnd() {
-        if (!CollectionUtils.isEmpty(searchListenersList)) {
-            searchRequestOperationsListener.onPhaseEnd(this);
-        }
+        this.searchRequestOperationsListener.ifPresent(searchRequestOperations -> { searchRequestOperations.onPhaseEnd(this); });
     }
 
     private void onPhaseStart(SearchPhase phase) {
         setCurrentPhase(phase);
-        if (!CollectionUtils.isEmpty(searchListenersList)) {
-            searchRequestOperationsListener.onPhaseStart(this);
-        }
+        this.searchRequestOperationsListener.ifPresent(searchRequestOperations -> { searchRequestOperations.onPhaseStart(this); });
     }
 
     private void executePhase(SearchPhase phase) {
@@ -710,9 +702,7 @@ public void sendSearchResponse(InternalSearchResponse internalSearchResponse, At
 
     @Override
     public final void onPhaseFailure(SearchPhase phase, String msg, Throwable cause) {
-        if (!CollectionUtils.isEmpty(searchListenersList)) {
-            searchRequestOperationsListener.onPhaseFailure(this);
-        }
+        this.searchRequestOperationsListener.ifPresent(searchRequestOperations -> searchRequestOperations.onPhaseFailure(this));
         raisePhaseFailure(new SearchPhaseExecutionException(phase.getName(), msg, cause, buildShardFailures()));
     }
 

server/src/main/java/org/opensearch/action/search/CanMatchPreFilterSearchPhase.java

@@ -91,7 +91,7 @@ final class CanMatchPreFilterSearchPhase extends AbstractSearchAsyncAction<CanMa
         SearchTask task,
         Function<GroupShardsIterator<SearchShardIterator>, SearchPhase> phaseFactory,
         SearchResponse.Clusters clusters,
-        List<SearchRequestOperationsListener> searchListenersList
+        SearchRequestOperationsListener searchRequestOperationsListener
     ) {
         // We set max concurrent shard requests to the number of shards so no throttling happens for can_match requests
         super(
@@ -112,7 +112,7 @@ final class CanMatchPreFilterSearchPhase extends AbstractSearchAsyncAction<CanMa
             new CanMatchSearchPhaseResults(shardsIts.size()),
             shardsIts.size(),
             clusters,
-            searchListenersList
+            searchRequestOperationsListener
         );
         this.phaseFactory = phaseFactory;
         this.shardsIts = shardsIts;

server/src/main/java/org/opensearch/action/search/SearchDfsQueryThenFetchAsyncAction.java

@@ -77,7 +77,7 @@ final class SearchDfsQueryThenFetchAsyncAction extends AbstractSearchAsyncAction
         final ClusterState clusterState,
         final SearchTask task,
         SearchResponse.Clusters clusters,
-        List<SearchRequestOperationsListener> searchListenersList
+        SearchRequestOperationsListener searchRequestOperationsListener
     ) {
         super(
             SearchPhaseName.DFS_PRE_QUERY.getName(),
@@ -97,7 +97,7 @@ final class SearchDfsQueryThenFetchAsyncAction extends AbstractSearchAsyncAction
             new ArraySearchPhaseResults<>(shardsIts.size()),
             request.getMaxConcurrentShardRequests(),
             clusters,
-            searchListenersList
+            searchRequestOperationsListener
         );
         this.queryPhaseResultConsumer = queryPhaseResultConsumer;
         this.searchPhaseController = searchPhaseController;

server/src/main/java/org/opensearch/action/search/SearchPhase.java

@@ -42,7 +42,7 @@
  *
  * @opensearch.internal
  */
-abstract class SearchPhase implements CheckedRunnable<IOException> {
+public abstract class SearchPhase implements CheckedRunnable<IOException> {
     private final String name;
     private long startTimeInNanos;
 

server/src/main/java/org/opensearch/action/search/SearchPhaseName.java

@@ -8,29 +8,18 @@
 
 package org.opensearch.action.search;
 
-import java.util.HashMap;
-import java.util.Map;
-
 /**
  * Enum for different Search Phases in OpenSearch
  * @opensearch.internal
  */
 public enum SearchPhaseName {
-    DFS_PRE_QUERY("dfs"),
+    DFS_PRE_QUERY("dfs_pre_query"),
     QUERY("query"),
     FETCH("fetch"),
     DFS_QUERY("dfs_query"),
     EXPAND("expand"),
     CAN_MATCH("can_match");
 
-    private static final Map<String, SearchPhaseName> STRING_TO_ENUM = new HashMap<>();
-
-    static {
-        for (SearchPhaseName searchPhaseName : values()) {
-            STRING_TO_ENUM.put(searchPhaseName.getName(), searchPhaseName);
-        }
-    }
-
     private final String name;
 
     SearchPhaseName(final String name) {
@@ -40,8 +29,4 @@ public enum SearchPhaseName {
     public String getName() {
         return name;
     }
-
-    public static SearchPhaseName getSearchPhaseName(String value) {
-        return STRING_TO_ENUM.get(value);
-    }
 }

server/src/main/java/org/opensearch/action/search/SearchQueryThenFetchAsyncAction.java

@@ -45,7 +45,6 @@
 import org.opensearch.search.query.QuerySearchResult;
 import org.opensearch.transport.Transport;
 
-import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.Executor;
@@ -83,7 +82,7 @@ class SearchQueryThenFetchAsyncAction extends AbstractSearchAsyncAction<SearchPh
         ClusterState clusterState,
         SearchTask task,
         SearchResponse.Clusters clusters,
-        List<SearchRequestOperationsListener> searchListenersList
+        SearchRequestOperationsListener searchRequestOperationsListener
     ) {
         super(
             SearchPhaseName.QUERY.getName(),
@@ -103,7 +102,7 @@ class SearchQueryThenFetchAsyncAction extends AbstractSearchAsyncAction<SearchPh
             resultConsumer,
             request.getMaxConcurrentShardRequests(),
             clusters,
-            searchListenersList
+            searchRequestOperationsListener
         );
         this.topDocsSize = SearchPhaseController.getTopDocsSize(request);
         this.trackTotalHitsUpTo = request.resolveTrackTotalHitsUpTo();