[Backport 2.x] [Search Pipeline]Handled default search pipeline for multiple indices

CHANGELOG.md

@@ -32,6 +32,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Batch mode for async fetching shard information in GatewayAllocator for unassigned shards ([#8746](https://github.com/opensearch-project/OpenSearch/pull/8746))
 - [Remote Store] Add settings for remote path type and hash algorithm ([#13225](https://github.com/opensearch-project/OpenSearch/pull/13225))
 - [Remote Store] Upload remote paths during remote enabled index creation ([#13386](https://github.com/opensearch-project/OpenSearch/pull/13386))
+- [Search Pipeline] Handle default pipeline for multiple indices ([#13276](https://github.com/opensearch-project/OpenSearch/pull/13276))
 
 ### Dependencies
 - Bump `org.apache.commons:commons-configuration2` from 2.10.0 to 2.10.1 ([#12896](https://github.com/opensearch-project/OpenSearch/pull/12896))

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

@@ -457,7 +457,7 @@ private void executeRequest(
             PipelinedRequest searchRequest;
             ActionListener<SearchResponse> listener;
             try {
-                searchRequest = searchPipelineService.resolvePipeline(originalSearchRequest);
+                searchRequest = searchPipelineService.resolvePipeline(originalSearchRequest, indexNameExpressionResolver);
                 listener = searchRequest.transformResponseListener(updatedListener);
             } catch (Exception e) {
                 updatedListener.onFailure(e);

server/src/main/java/org/opensearch/search/pipeline/SearchPipelineService.java

@@ -23,6 +23,7 @@
 import org.opensearch.cluster.ClusterState;
 import org.opensearch.cluster.ClusterStateApplier;
 import org.opensearch.cluster.metadata.IndexMetadata;
+import org.opensearch.cluster.metadata.IndexNameExpressionResolver;
 import org.opensearch.cluster.metadata.Metadata;
 import org.opensearch.cluster.node.DiscoveryNode;
 import org.opensearch.cluster.service.ClusterManagerTaskKeys;
@@ -35,10 +36,12 @@
 import org.opensearch.common.xcontent.XContentHelper;
 import org.opensearch.core.action.ActionListener;
 import org.opensearch.core.common.io.stream.NamedWriteableRegistry;
+import org.opensearch.core.index.Index;
 import org.opensearch.core.service.ReportingService;
 import org.opensearch.core.xcontent.NamedXContentRegistry;
 import org.opensearch.env.Environment;
 import org.opensearch.gateway.GatewayService;
+import org.opensearch.index.IndexNotFoundException;
 import org.opensearch.index.IndexSettings;
 import org.opensearch.index.analysis.AnalysisRegistry;
 import org.opensearch.ingest.ConfigurationUtils;
@@ -62,6 +65,8 @@
 /**
  * The main entry point for search pipelines. Handles CRUD operations and exposes the API to execute search pipelines
  * against requests and responses.
+ *
+ * @opensearch.internal
  */
 public class SearchPipelineService implements ClusterStateApplier, ReportingService<SearchPipelineInfo> {
 
@@ -360,7 +365,7 @@ static ClusterState innerDelete(DeleteSearchPipelineRequest request, ClusterStat
         return newState.build();
     }
 
-    public PipelinedRequest resolvePipeline(SearchRequest searchRequest) {
+    public PipelinedRequest resolvePipeline(SearchRequest searchRequest, IndexNameExpressionResolver indexNameExpressionResolver) {
         Pipeline pipeline = Pipeline.NO_OP_PIPELINE;
 
         if (searchRequest.source() != null && searchRequest.source().searchPipelineSource() != null) {
@@ -390,14 +395,27 @@ public PipelinedRequest resolvePipeline(SearchRequest searchRequest) {
             if (searchRequest.pipeline() != null) {
                 // Named pipeline specified for the request
                 pipelineId = searchRequest.pipeline();
-            } else if (state != null && searchRequest.indices() != null && searchRequest.indices().length == 1) {
-                // Check for index default pipeline
-                IndexMetadata indexMetadata = state.metadata().index(searchRequest.indices()[0]);
-                if (indexMetadata != null) {
-                    Settings indexSettings = indexMetadata.getSettings();
-                    if (IndexSettings.DEFAULT_SEARCH_PIPELINE.exists(indexSettings)) {
-                        pipelineId = IndexSettings.DEFAULT_SEARCH_PIPELINE.get(indexSettings);
+            } else if (state != null && searchRequest.indices() != null && searchRequest.indices().length != 0) {
+                try {
+                    // Check for index default pipeline
+                    Index[] concreteIndices = indexNameExpressionResolver.concreteIndices(state, searchRequest);
+                    for (Index index : concreteIndices) {
+                        IndexMetadata indexMetadata = state.metadata().index(index);
+                        if (indexMetadata != null) {
+                            Settings indexSettings = indexMetadata.getSettings();
+                            if (IndexSettings.DEFAULT_SEARCH_PIPELINE.exists(indexSettings)) {
+                                String currentPipelineId = IndexSettings.DEFAULT_SEARCH_PIPELINE.get(indexSettings);
+                                if (NOOP_PIPELINE_ID.equals(pipelineId)) {
+                                    pipelineId = currentPipelineId;
+                                } else if (!pipelineId.equals(currentPipelineId)) {
+                                    pipelineId = NOOP_PIPELINE_ID;
+                                    break;
+                                }
+                            }
+                        }
                     }
+                } catch (IndexNotFoundException e) {
+                    logger.debug("Default pipeline not applied for {}", (Object) searchRequest.indices());
                 }
             }
             if (NOOP_PIPELINE_ID.equals(pipelineId) == false) {