API changes for stream transport and stream based search transport action

CHANGELOG.md

@@ -45,6 +45,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Added approximation support for range queries with now in date field ([#18511](https://github.com/opensearch-project/OpenSearch/pull/18511))
 - Upgrade to protobufs 0.6.0 and clean up deprecated TermQueryProtoUtils code ([#18880](https://github.com/opensearch-project/OpenSearch/pull/18880))
 - Prevent shard initialization failure due to streaming consumer errors ([#18877](https://github.com/opensearch-project/OpenSearch/pull/18877))
+- APIs for stream transport and new stream-based search api action ([#18722](https://github.com/opensearch-project/OpenSearch/pull/18722))
 
 ### Changed
 - Update Subject interface to use CheckedRunnable ([#18570](https://github.com/opensearch-project/OpenSearch/issues/18570))

server/src/main/java/org/opensearch/OpenSearchServerException.java

@@ -23,6 +23,7 @@
 import static org.opensearch.Version.V_2_6_0;
 import static org.opensearch.Version.V_2_7_0;
 import static org.opensearch.Version.V_3_0_0;
+import static org.opensearch.Version.V_3_2_0;
 
 /**
  * Utility class to register server exceptions
@@ -1232,5 +1233,13 @@ public static void registerExceptions() {
                 V_3_0_0
             )
         );
+        registerExceptionHandle(
+            new OpenSearchExceptionHandle(
+                org.opensearch.transport.stream.StreamException.class,
+                org.opensearch.transport.stream.StreamException::new,
+                177,
+                V_3_2_0
+            )
+        );
     }
 }

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

@@ -286,6 +286,8 @@
 import org.opensearch.action.search.PutSearchPipelineTransportAction;
 import org.opensearch.action.search.SearchAction;
 import org.opensearch.action.search.SearchScrollAction;
+import org.opensearch.action.search.StreamSearchAction;
+import org.opensearch.action.search.StreamTransportSearchAction;
 import org.opensearch.action.search.TransportClearScrollAction;
 import org.opensearch.action.search.TransportCreatePitAction;
 import org.opensearch.action.search.TransportDeletePitAction;
@@ -734,6 +736,9 @@ public <Request extends ActionRequest, Response extends ActionResponse> void reg
         actions.register(MultiGetAction.INSTANCE, TransportMultiGetAction.class, TransportShardMultiGetAction.class);
         actions.register(BulkAction.INSTANCE, TransportBulkAction.class, TransportShardBulkAction.class);
         actions.register(SearchAction.INSTANCE, TransportSearchAction.class);
+        if (FeatureFlags.isEnabled(FeatureFlags.STREAM_TRANSPORT)) {
+            actions.register(StreamSearchAction.INSTANCE, StreamTransportSearchAction.class);
+        }
         actions.register(SearchScrollAction.INSTANCE, TransportSearchScrollAction.class);
         actions.register(MultiSearchAction.INSTANCE, TransportMultiSearchAction.class);
         actions.register(ExplainAction.INSTANCE, TransportExplainAction.class);

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

@@ -68,6 +68,10 @@ public SearchRequestBuilder(OpenSearchClient client, SearchAction action) {
         super(client, action, new SearchRequest());
     }
 
+    public SearchRequestBuilder(OpenSearchClient client, StreamSearchAction action) {
+        super(client, action, new SearchRequest());
+    }
+
     /**
      * Sets the indices the search will be executed on.
      */

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

@@ -102,7 +102,7 @@ public class SearchTransportService {
     public static final String UPDATE_READER_CONTEXT_ACTION_NAME = "indices:data/read/search[update_context]";
 
     private final TransportService transportService;
-    private final BiFunction<Transport.Connection, SearchActionListener, ActionListener> responseWrapper;
+    protected final BiFunction<Transport.Connection, SearchActionListener, ActionListener> responseWrapper;
     private final Map<String, Long> clientConnections = ConcurrentCollections.newConcurrentMapWithAggressiveConcurrency();
 
     public SearchTransportService(

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

@@ -0,0 +1,27 @@
+/*
+ * 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.search;
+
+import org.opensearch.action.ActionType;
+
+/**
+ * Transport action for executing a search
+ *
+ * @opensearch.internal
+ */
+public class StreamSearchAction extends ActionType<SearchResponse> {
+
+    public static final StreamSearchAction INSTANCE = new StreamSearchAction();
+    public static final String NAME = "indices:data/read/search/stream";
+
+    private StreamSearchAction() {
+        super(NAME, SearchResponse::new);
+    }
+
+}