Return 404 for missing indices in cluster health API instead of RED with timeout

Author: Prakash Bhardwaj

server/src/internalClusterTest/java/org/opensearch/cluster/ClusterHealthIT.java

@@ -46,6 +46,7 @@
 import org.opensearch.common.action.ActionFuture;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.common.unit.TimeValue;
+import org.opensearch.index.IndexNotFoundException;
 import org.opensearch.test.InternalTestCluster;
 import org.opensearch.test.OpenSearchIntegTestCase;
 
@@ -83,19 +84,17 @@ public void testSimpleLocalHealth() {
 
     public void testHealth() {
         logger.info("--> running cluster health on an index that does not exists");
-        ClusterHealthResponse healthResponse = client().admin()
-            .cluster()
-            .prepareHealth("test1")
-            .setWaitForYellowStatus()
-            .setTimeout("1s")
-            .execute()
-            .actionGet();
-        assertThat(healthResponse.isTimedOut(), equalTo(true));
-        assertThat(healthResponse.getStatus(), equalTo(ClusterHealthStatus.RED));
-        assertThat(healthResponse.getIndices().isEmpty(), equalTo(true));
-
+        expectThrows(IndexNotFoundException.class,()->{
+            client().admin()
+                .cluster()
+                .prepareHealth("test1")
+                .setWaitForYellowStatus()
+                .setTimeout("1s")
+                .execute()
+                .actionGet();
+        });
         logger.info("--> running cluster wide health");
-        healthResponse = client().admin().cluster().prepareHealth().setWaitForGreenStatus().setTimeout("10s").execute().actionGet();
+        ClusterHealthResponse healthResponse = client().admin().cluster().prepareHealth().setWaitForGreenStatus().setTimeout("10s").execute().actionGet();
         assertThat(healthResponse.isTimedOut(), equalTo(false));
         assertThat(healthResponse.getStatus(), equalTo(ClusterHealthStatus.GREEN));
         assertThat(healthResponse.getIndices().isEmpty(), equalTo(true));
@@ -302,6 +301,7 @@ public void run() {
     }
 
     public void testWaitForEventsRetriesIfOtherConditionsNotMet() {
+        createIndex("index");
         final ActionFuture<ClusterHealthResponse> healthResponseFuture = client().admin()
             .cluster()
             .prepareHealth("index")
@@ -338,7 +338,6 @@ public void clusterStateProcessed(String source, ClusterState oldState, ClusterS
         });
 
         try {
-            createIndex("index");
             assertFalse(client().admin().cluster().prepareHealth("index").setWaitForGreenStatus().get().isTimedOut());
 
             // at this point the original health response should not have returned: there was never a point where the index was green AND

server/src/main/java/org/opensearch/action/admin/cluster/health/TransportClusterHealthAction.java

@@ -419,13 +419,9 @@ static int prepareResponse(
             }
         }
         if (CollectionUtils.isEmpty(request.indices()) == false) {
-            try {
-                indexNameExpressionResolver.concreteIndexNames(clusterState, IndicesOptions.strictExpand(), request);
-                waitForCounter++;
-            } catch (IndexNotFoundException e) {
-                response.setStatus(ClusterHealthStatus.RED); // no indices, make sure its RED
-                // missing indices, wait a bit more...
-            }
+            indexNameExpressionResolver.concreteIndexNames(clusterState, IndicesOptions.strictExpand(), request);
+            waitForCounter++;
+
         }
         if (!request.waitForNodes().isEmpty()) {
             if (request.waitForNodes().startsWith(">=")) {