fix ingestion pause state initialization on replica promotion (opensearch-project#19212)

Signed-off-by: Varun Bharadwaj <varunbharadwaj1995@gmail.com>

Author: varunbharadwaj

CHANGELOG.md

@@ -33,6 +33,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Grant access to testclusters dir for tests ([#19085](https://github.com/opensearch-project/OpenSearch/issues/19085))
 - Fix assertion error when collapsing search results with concurrent segment search enabled ([#19053](https://github.com/opensearch-project/OpenSearch/pull/19053))
 - Fix skip_unavailable setting changing to default during node drop issue ([#18766](https://github.com/opensearch-project/OpenSearch/pull/18766))
+- Fix pull-based ingestion pause state initialization during replica promotion ([#19212](https://github.com/opensearch-project/OpenSearch/pull/19212))
 
 ### Dependencies
 - Bump `com.netflix.nebula.ospackage-base` from 12.0.0 to 12.1.0 ([#19019](https://github.com/opensearch-project/OpenSearch/pull/19019))

plugins/ingestion-kafka/src/internalClusterTest/java/org/opensearch/plugin/kafka/RemoteStoreKafkaIT.java

@@ -191,11 +191,13 @@ public void testPauseAndResumeIngestion() throws Exception {
         produceData("2", "name2", "20");
         internalCluster().startClusterManagerOnlyNode();
         final String nodeA = internalCluster().startDataOnlyNode();
-        final String nodeB = internalCluster().startDataOnlyNode();
 
         createIndexWithDefaultSettings(1, 1);
+        ensureYellowAndNoInitializingShards(indexName);
+        waitForSearchableDocs(2, Arrays.asList(nodeA));
+        final String nodeB = internalCluster().startDataOnlyNode();
         ensureGreen(indexName);
-        waitForSearchableDocs(2, Arrays.asList(nodeA, nodeB));
+        assertTrue(nodeA.equals(primaryNodeName(indexName)));
 
         // pause ingestion
         PauseIngestionResponse pauseResponse = pauseIngestion(indexName);
@@ -219,12 +221,13 @@ public void testPauseAndResumeIngestion() throws Exception {
         client().admin().cluster().prepareReroute().add(new AllocateReplicaAllocationCommand(indexName, 0, nodeC)).get();
         ensureGreen(indexName);
         assertTrue(nodeC.equals(replicaNodeName(indexName)));
-        assertEquals(2, getSearchableDocCount(nodeB));
         waitForState(() -> {
             GetIngestionStateResponse ingestionState = getIngestionState(indexName);
-            return Arrays.stream(ingestionState.getShardStates())
-                .allMatch(state -> state.isPollerPaused() && state.pollerState().equalsIgnoreCase("paused"));
+            return ingestionState.getFailedShards() == 0
+                && Arrays.stream(ingestionState.getShardStates())
+                    .allMatch(state -> state.isPollerPaused() && state.pollerState().equalsIgnoreCase("paused"));
         });
+        assertEquals(2, getSearchableDocCount(nodeB));
 
         // resume ingestion
         ResumeIngestionResponse resumeResponse = resumeIngestion(indexName);

server/src/main/java/org/opensearch/indices/pollingingest/DefaultStreamPoller.java

@@ -157,6 +157,8 @@ private DefaultStreamPoller(
         this.errorStrategy = errorStrategy;
         this.indexName = indexSettings.getIndex().getName();
 
+        // handle initial poller states
+        this.paused = initialState == State.PAUSED;
     }
 
     @Override