Fix flaky RemoteIndexRecoveryIT testRerouteRecovery test #9580 (#11918)

Signed-off-by: Ashish Singh <ssashish@amazon.com>

Author: ashking94

server/src/internalClusterTest/java/org/opensearch/indices/recovery/IndexRecoveryIT.java

@@ -523,12 +523,12 @@ public void testRerouteRecovery() throws Exception {
 
         logger.info("--> waiting for recovery to start both on source and target");
         final Index index = resolveIndex(INDEX_NAME);
-        assertBusy(() -> {
+        assertBusyWithFixedSleepTime(() -> {
             IndicesService indicesService = internalCluster().getInstance(IndicesService.class, nodeA);
             assertThat(indicesService.indexServiceSafe(index).getShard(0).recoveryStats().currentAsSource(), equalTo(1));
             indicesService = internalCluster().getInstance(IndicesService.class, nodeB);
             assertThat(indicesService.indexServiceSafe(index).getShard(0).recoveryStats().currentAsTarget(), equalTo(1));
-        });
+        }, TimeValue.timeValueSeconds(10), TimeValue.timeValueMillis(500));
 
         logger.info("--> request recoveries");
         RecoveryResponse response = client().admin().indices().prepareRecoveries(INDEX_NAME).execute().actionGet();

server/src/internalClusterTest/java/org/opensearch/remotestore/RemoteIndexRecoveryIT.java

@@ -157,10 +157,4 @@ public void testDisconnectsDuringRecovery() {
     public void testReplicaRecovery() {
 
     }
-
-    @AwaitsFix(bugUrl = "https://github.com/opensearch-project/OpenSearch/issues/9580")
-    public void testRerouteRecovery() {
-
-    }
-
 }

test/framework/src/main/java/org/opensearch/test/OpenSearchTestCase.java

@@ -83,6 +83,7 @@
 import org.opensearch.common.settings.Settings;
 import org.opensearch.common.time.DateUtils;
 import org.opensearch.common.time.FormatNames;
+import org.opensearch.common.unit.TimeValue;
 import org.opensearch.common.util.MockBigArrays;
 import org.opensearch.common.util.MockPageCacheRecycler;
 import org.opensearch.common.util.concurrent.ThreadContext;
@@ -1095,6 +1096,38 @@ public static void assertBusy(CheckedRunnable<Exception> codeBlock, long maxWait
         }
     }
 
+    /**
+     * Runs the code block for the provided max wait time and sleeping for fixed sleep time, waiting for no assertions to trip.
+     */
+    public static void assertBusyWithFixedSleepTime(CheckedRunnable<Exception> codeBlock, TimeValue maxWaitTime, TimeValue sleepTime)
+        throws Exception {
+        long maxTimeInMillis = maxWaitTime.millis();
+        long sleepTimeInMillis = sleepTime.millis();
+        if (sleepTimeInMillis > maxTimeInMillis) {
+            throw new IllegalArgumentException("sleepTime is more than the maxWaitTime");
+        }
+        long sum = 0;
+        List<AssertionError> failures = new ArrayList<>();
+        while (sum <= maxTimeInMillis) {
+            try {
+                codeBlock.run();
+                return;
+            } catch (AssertionError e) {
+                failures.add(e);
+            }
+            sum += sleepTimeInMillis;
+            Thread.sleep(sleepTimeInMillis);
+        }
+        try {
+            codeBlock.run();
+        } catch (AssertionError e) {
+            for (AssertionError failure : failures) {
+                e.addSuppressed(failure);
+            }
+            throw e;
+        }
+    }
+
     /**
      * Periodically execute the supplied function until it returns true, or a timeout
      * is reached. This version uses a timeout of 10 seconds. If at all possible,