Fix race in testCreateIndexWaitsForAllActiveShards

When index creation is not acknowledged (due to a very low request timeout) it is possible that the index is still created.
If a subsequent index-exists request completes before the cluster state of the index creation has been fully applied, it
might miss the newly created index.

core/src/test/java/org/elasticsearch/action/support/ActiveShardsObserverIT.java

@@ -35,7 +35,6 @@ import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAcke
 public class ActiveShardsObserverIT extends ESIntegTestCase {
 
     public void testCreateIndexNoActiveShardsTimesOut() throws Exception {
-        final String indexName = "test-idx";
         Settings.Builder settingsBuilder = Settings.builder()
                                                .put(indexSettings())
                                                .put(INDEX_NUMBER_OF_SHARDS_SETTING.getKey(), randomIntBetween(1, 5))
@@ -45,7 +44,7 @@ public class ActiveShardsObserverIT extends ESIntegTestCase {
             settingsBuilder.put("index.routing.allocation.exclude._name", exclude);
         }
         Settings settings = settingsBuilder.build();
-        assertFalse(prepareCreate(indexName)
+        assertFalse(prepareCreate("test-idx")
                        .setSettings(settings)
                        .setWaitForActiveShards(randomBoolean() ? ActiveShardCount.from(1) : ActiveShardCount.ALL)
                        .setTimeout("100ms")
@@ -54,7 +53,6 @@ public class ActiveShardsObserverIT extends ESIntegTestCase {
     }
 
     public void testCreateIndexNoActiveShardsNoWaiting() throws Exception {
-        final String indexName = "test-idx";
         Settings.Builder settingsBuilder = Settings.builder()
                                                .put(indexSettings())
                                                .put(INDEX_NUMBER_OF_SHARDS_SETTING.getKey(), randomIntBetween(1, 5))
@@ -64,7 +62,7 @@ public class ActiveShardsObserverIT extends ESIntegTestCase {
             settingsBuilder.put("index.routing.allocation.exclude._name", exclude);
         }
         Settings settings = settingsBuilder.build();
-        CreateIndexResponse response = prepareCreate(indexName)
+        CreateIndexResponse response = prepareCreate("test-idx")
                                            .setSettings(settings)
                                            .setWaitForActiveShards(ActiveShardCount.from(0))
                                            .get();
@@ -72,7 +70,6 @@ public class ActiveShardsObserverIT extends ESIntegTestCase {
     }
 
     public void testCreateIndexNotEnoughActiveShardsTimesOut() throws Exception {
-        final String indexName = "test-idx";
         final int numDataNodes = internalCluster().numDataNodes();
         final int numReplicas = numDataNodes + randomInt(4);
         Settings settings = Settings.builder()
@@ -80,7 +77,7 @@ public class ActiveShardsObserverIT extends ESIntegTestCase {
                                 .put(INDEX_NUMBER_OF_SHARDS_SETTING.getKey(), randomIntBetween(1, 7))
                                 .put(INDEX_NUMBER_OF_REPLICAS_SETTING.getKey(), numReplicas)
                                 .build();
-        assertFalse(prepareCreate(indexName)
+        assertFalse(prepareCreate("test-idx")
                        .setSettings(settings)
                        .setWaitForActiveShards(ActiveShardCount.from(randomIntBetween(numDataNodes + 1, numReplicas + 1)))
                        .setTimeout("100ms")
@@ -100,7 +97,6 @@ public class ActiveShardsObserverIT extends ESIntegTestCase {
     }
 
     public void testCreateIndexWaitsForAllActiveShards() throws Exception {
-        final String indexName = "test-idx";
         // not enough data nodes, index creation times out
         final int numReplicas = internalCluster().numDataNodes() + randomInt(4);
         Settings settings = Settings.builder()
@@ -108,23 +104,20 @@ public class ActiveShardsObserverIT extends ESIntegTestCase {
                                 .put(INDEX_NUMBER_OF_SHARDS_SETTING.getKey(), randomIntBetween(1, 5))
                                 .put(INDEX_NUMBER_OF_REPLICAS_SETTING.getKey(), numReplicas)
                                 .build();
-        assertFalse(prepareCreate(indexName)
+        assertFalse(prepareCreate("test-idx1")
                        .setSettings(settings)
                        .setWaitForActiveShards(ActiveShardCount.ALL)
                        .setTimeout("100ms")
                        .get()
                        .isShardsAcked());
-        if (client().admin().indices().prepareExists(indexName).get().isExists()) {
-            assertAcked(client().admin().indices().prepareDelete(indexName));
-        }
 
         // enough data nodes, all shards are active
-         settings = Settings.builder()
+        settings = Settings.builder()
                         .put(indexSettings())
                         .put(INDEX_NUMBER_OF_SHARDS_SETTING.getKey(), randomIntBetween(1, 7))
                         .put(INDEX_NUMBER_OF_REPLICAS_SETTING.getKey(), internalCluster().numDataNodes() - 1)
                         .build();
-        assertAcked(prepareCreate(indexName).setSettings(settings).setWaitForActiveShards(ActiveShardCount.ALL).get());
+        assertAcked(prepareCreate("test-idx2").setSettings(settings).setWaitForActiveShards(ActiveShardCount.ALL).get());
     }
 
     public void testCreateIndexStopsWaitingWhenIndexDeleted() throws Exception {