[ML][Data Frame] only complete task after state persistence (#43230)

* [ML][Data Frame] only complete task after state persistence

There is a race condition where the task could be completed, but there
is still a pending document write. This change moves
the task cancellation into the actionlistener of the state persistence.

intermediate commit

intermediate commit

* removing unused import

* removing unused const

* refreshing internal index after waiting for task to complete

* adjusting test data generation

x-pack/plugin/data-frame/qa/multi-node-tests/src/test/java/org/elasticsearch/xpack/dataframe/integration/DataFrameIntegTestCase.java

@@ -65,8 +65,6 @@ import static org.hamcrest.core.Is.is;
 
 abstract class DataFrameIntegTestCase extends ESRestTestCase {
 
-    protected static final String REVIEWS_INDEX_NAME = "data_frame_reviews";
-
     private Map<String, DataFrameTransformConfig> transformConfigs = new HashMap<>();
 
     protected void cleanUp() throws IOException {
@@ -213,8 +211,7 @@ abstract class DataFrameIntegTestCase extends ESRestTestCase {
             .build();
     }
 
-    protected void createReviewsIndex() throws Exception {
-        final int numDocs = 1000;
+    protected void createReviewsIndex(String indexName, int numDocs) throws Exception {
         RestHighLevelClient restClient = new TestRestHighLevelClient();
 
         // create mapping
@@ -241,12 +238,12 @@ abstract class DataFrameIntegTestCase extends ESRestTestCase {
             }
             builder.endObject();
             CreateIndexResponse response =
-                restClient.indices().create(new CreateIndexRequest(REVIEWS_INDEX_NAME).mapping(builder), RequestOptions.DEFAULT);
+                restClient.indices().create(new CreateIndexRequest(indexName).mapping(builder), RequestOptions.DEFAULT);
             assertThat(response.isAcknowledged(), is(true));
         }
 
         // create index
-        BulkRequest bulk = new BulkRequest(REVIEWS_INDEX_NAME);
+        BulkRequest bulk = new BulkRequest(indexName);
         int day = 10;
         for (int i = 0; i < numDocs; i++) {
             long user = i % 28;
@@ -256,7 +253,7 @@ abstract class DataFrameIntegTestCase extends ESRestTestCase {
             int min = 10 + (i % 49);
             int sec = 10 + (i % 49);
 
-            String date_string = "2017-01-" + day + "T" + hour + ":" + min + ":" + sec + "Z";
+            String date_string = "2017-01-" + (day < 10 ? "0" + day : day) + "T" + hour + ":" + min + ":" + sec + "Z";
 
             StringBuilder sourceBuilder = new StringBuilder();
             sourceBuilder.append("{\"user_id\":\"")
@@ -277,13 +274,13 @@ abstract class DataFrameIntegTestCase extends ESRestTestCase {
             if (i % 50 == 0) {
                 BulkResponse response = restClient.bulk(bulk, RequestOptions.DEFAULT);
                 assertThat(response.buildFailureMessage(), response.hasFailures(), is(false));
-                bulk = new BulkRequest(REVIEWS_INDEX_NAME);
-                day += 1;
+                bulk = new BulkRequest(indexName);
+                day = (day + 1) % 28;
             }
         }
         BulkResponse response = restClient.bulk(bulk, RequestOptions.DEFAULT);
         assertThat(response.buildFailureMessage(), response.hasFailures(), is(false));
-        restClient.indices().refresh(new RefreshRequest(REVIEWS_INDEX_NAME), RequestOptions.DEFAULT);
+        restClient.indices().refresh(new RefreshRequest(indexName), RequestOptions.DEFAULT);
     }
 
     protected Map<String, Object> toLazy(ToXContent parsedObject) throws Exception {

x-pack/plugin/data-frame/qa/multi-node-tests/src/test/java/org/elasticsearch/xpack/dataframe/integration/DataFrameTransformIT.java

@@ -30,7 +30,8 @@ public class DataFrameTransformIT extends DataFrameIntegTestCase {
     }
 
     public void testDataFrameTransformCrud() throws Exception {
-        createReviewsIndex();
+        String indexName = "basic-crud-reviews";
+        createReviewsIndex(indexName, 100);
 
         Map<String, SingleGroupSource> groups = new HashMap<>();
         groups.put("by-day", createDateHistogramGroupSourceWithCalendarInterval("timestamp", DateHistogramInterval.DAY, null, null));
@@ -45,7 +46,7 @@ public class DataFrameTransformIT extends DataFrameIntegTestCase {
             groups,
             aggs,
             "reviews-by-user-business-day",
-            REVIEWS_INDEX_NAME);
+            indexName);
 
         assertTrue(putDataFrameTransform(config, RequestOptions.DEFAULT).isAcknowledged());
         assertTrue(startDataFrameTransform(config.getId(), RequestOptions.DEFAULT).isAcknowledged());
@@ -56,7 +57,8 @@ public class DataFrameTransformIT extends DataFrameIntegTestCase {
         assertBusy(() ->
             assertThat(getDataFrameTransformStats(config.getId()).getTransformsStateAndStats().get(0).getTransformState().getIndexerState(),
                 equalTo(IndexerState.STOPPED)));
+        stopDataFrameTransform(config.getId());
+        deleteDataFrameTransform(config.getId());
     }
 
-
 }

x-pack/plugin/data-frame/src/main/java/org/elasticsearch/xpack/dataframe/action/TransportStopDataFrameTransformAction.java

@@ -5,6 +5,8 @@
  */
 package org.elasticsearch.xpack.dataframe.action;
 
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.elasticsearch.ElasticsearchStatusException;
 import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.action.ActionListenerResponseHandler;
@@ -12,6 +14,7 @@ import org.elasticsearch.action.FailedNodeException;
 import org.elasticsearch.action.TaskOperationFailure;
 import org.elasticsearch.action.support.ActionFilters;
 import org.elasticsearch.action.support.tasks.TransportTasksAction;
+import org.elasticsearch.client.Client;
 import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.cluster.node.DiscoveryNodes;
 import org.elasticsearch.cluster.service.ClusterService;
@@ -26,6 +29,7 @@ import org.elasticsearch.transport.TransportService;
 import org.elasticsearch.xpack.core.action.util.PageParams;
 import org.elasticsearch.xpack.core.dataframe.action.StopDataFrameTransformAction;
 import org.elasticsearch.xpack.core.dataframe.transforms.DataFrameTransformTaskState;
+import org.elasticsearch.xpack.dataframe.persistence.DataFrameInternalIndex;
 import org.elasticsearch.xpack.dataframe.persistence.DataFrameTransformsConfigManager;
 import org.elasticsearch.xpack.dataframe.transforms.DataFrameTransformTask;
 
@@ -38,20 +42,25 @@ public class TransportStopDataFrameTransformAction extends
         TransportTasksAction<DataFrameTransformTask, StopDataFrameTransformAction.Request,
         StopDataFrameTransformAction.Response, StopDataFrameTransformAction.Response> {
 
+    private static final Logger logger = LogManager.getLogger(TransportStopDataFrameTransformAction.class);
+
     private final ThreadPool threadPool;
     private final DataFrameTransformsConfigManager dataFrameTransformsConfigManager;
     private final PersistentTasksService persistentTasksService;
+    private final Client client;
 
     @Inject
     public TransportStopDataFrameTransformAction(TransportService transportService, ActionFilters actionFilters,
                                                  ClusterService clusterService, ThreadPool threadPool,
                                                  PersistentTasksService persistentTasksService,
-                                                 DataFrameTransformsConfigManager dataFrameTransformsConfigManager) {
+                                                 DataFrameTransformsConfigManager dataFrameTransformsConfigManager,
+                                                 Client client) {
         super(StopDataFrameTransformAction.NAME, clusterService, transportService, actionFilters, StopDataFrameTransformAction.Request::new,
                 StopDataFrameTransformAction.Response::new, StopDataFrameTransformAction.Response::new, ThreadPool.Names.SAME);
         this.threadPool = threadPool;
         this.dataFrameTransformsConfigManager = dataFrameTransformsConfigManager;
         this.persistentTasksService = persistentTasksService;
+        this.client = client;
     }
 
     @Override
@@ -132,12 +141,26 @@ public class TransportStopDataFrameTransformAction extends
     waitForStopListener(StopDataFrameTransformAction.Request request,
                         ActionListener<StopDataFrameTransformAction.Response> listener) {
 
+        ActionListener<StopDataFrameTransformAction.Response> onStopListener = ActionListener.wrap(
+            waitResponse ->
+                client.admin()
+                    .indices()
+                    .prepareRefresh(DataFrameInternalIndex.INDEX_NAME)
+                    .execute(ActionListener.wrap(
+                        r -> listener.onResponse(waitResponse),
+                        e -> {
+                            logger.info("Failed to refresh internal index after delete", e);
+                            listener.onResponse(waitResponse);
+                        })
+                    ),
+            listener::onFailure
+        );
         return ActionListener.wrap(
                 response -> {
                     // Wait until the persistent task is stopped
                     // Switch over to Generic threadpool so we don't block the network thread
                     threadPool.generic().execute(() ->
-                        waitForDataFrameStopped(request.getExpandedIds(), request.getTimeout(), listener));
+                        waitForDataFrameStopped(request.getExpandedIds(), request.getTimeout(), onStopListener));
                 },
                 listener::onFailure
         );

x-pack/plugin/data-frame/src/main/java/org/elasticsearch/xpack/dataframe/transforms/DataFrameTransformTask.java

@@ -248,7 +248,7 @@ public class DataFrameTransformTask extends AllocatedPersistentTask implements S
 
         IndexerState state = getIndexer().stop();
         if (state == IndexerState.STOPPED) {
-            //doSaveState calls `onStop` when the task state is `STOPPED`
+            getIndexer().onStop();
             getIndexer().doSaveState(state, getIndexer().getPosition(), () -> {});
         }
     }
@@ -610,7 +610,7 @@ public class DataFrameTransformTask extends AllocatedPersistentTask implements S
                             r -> {
                                 // for auto stop shutdown the task
                                 if (state.getTaskState().equals(DataFrameTransformTaskState.STOPPED)) {
-                                    onStop();
+                                    transformTask.shutdown();
                                 }
                                 next.run();
                             },
@@ -620,7 +620,7 @@ public class DataFrameTransformTask extends AllocatedPersistentTask implements S
                                     "Failure updating stats of transform: " + statsExc.getMessage());
                                 // for auto stop shutdown the task
                                 if (state.getTaskState().equals(DataFrameTransformTaskState.STOPPED)) {
-                                    onStop();
+                                    transformTask.shutdown();
                                 }
                                 next.run();
                             }
@@ -666,7 +666,6 @@ public class DataFrameTransformTask extends AllocatedPersistentTask implements S
         protected void onStop() {
             auditor.info(transformConfig.getId(), "Data frame transform has stopped.");
             logger.info("Data frame transform [{}] indexer has stopped", transformConfig.getId());
-            transformTask.shutdown();
         }
 
         @Override