Cancel sub stages in FLUSHING state

presto-main/src/main/java/io/prestosql/execution/scheduler/SqlQueryScheduler.java

@@ -421,7 +421,7 @@ else if (partitioningHandle.equals(SCALED_WRITER_DISTRIBUTION)) {
         }
         Set<SqlStageExecution> childStages = childStagesBuilder.build();
         stage.addStateChangeListener(newState -> {
-            if (newState.isDone()) {
+            if (newState == FLUSHING || newState.isDone()) {
                 childStages.forEach(SqlStageExecution::cancel);
             }
         });

presto-main/src/main/java/io/prestosql/server/testing/TestingPrestoServer.java

@@ -364,6 +364,11 @@ public Plan getQueryPlan(QueryId queryId)
         return queryManager.getQueryPlan(queryId);
     }
 
+    public QueryInfo getFullQueryInfo(QueryId queryId)
+    {
+        return queryManager.getFullQueryInfo(queryId);
+    }
+
     public void addFinalQueryInfoListener(QueryId queryId, StateChangeListener<QueryInfo> stateChangeListener)
     {
         queryManager.addFinalQueryInfoListener(queryId, stateChangeListener);

presto-tests/src/test/java/io/prestosql/execution/TestFlushingStageState.java

@@ -0,0 +1,78 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.prestosql.execution;
+
+import com.google.common.collect.ImmutableMap;
+import io.airlift.units.Duration;
+import io.prestosql.spi.QueryId;
+import io.prestosql.testing.DistributedQueryRunner;
+import io.prestosql.tests.tpch.TpchQueryRunnerBuilder;
+import org.testng.annotations.AfterClass;
+import org.testng.annotations.BeforeClass;
+import org.testng.annotations.Test;
+
+import static io.prestosql.SessionTestUtils.TEST_SESSION;
+import static io.prestosql.execution.QueryState.RUNNING;
+import static io.prestosql.execution.StageState.CANCELED;
+import static io.prestosql.execution.StageState.FLUSHING;
+import static io.prestosql.execution.TestQueryRunnerUtil.createQuery;
+import static io.prestosql.execution.TestQueryRunnerUtil.waitForQueryState;
+import static io.prestosql.testing.assertions.Assert.assertEventually;
+import static java.util.concurrent.TimeUnit.SECONDS;
+import static org.testng.Assert.assertEquals;
+
+public class TestFlushingStageState
+{
+    private DistributedQueryRunner queryRunner;
+
+    @BeforeClass
+    public void setup()
+            throws Exception
+    {
+        queryRunner = TpchQueryRunnerBuilder.builder().buildWithoutCatalogs();
+        queryRunner.createCatalog("tpch", "tpch", ImmutableMap.of("tpch.splits-per-node", "10000"));
+    }
+
+    @Test(timeOut = 30_000)
+    public void testFlushingState()
+            throws Exception
+    {
+        QueryId queryId = createQuery(queryRunner, TEST_SESSION, "SELECT * FROM tpch.sf1000.lineitem limit 1");
+        waitForQueryState(queryRunner, queryId, RUNNING);
+
+        // wait for the query to finish producing results, but don't poll them
+        assertEventually(
+                new Duration(10, SECONDS),
+                () -> assertEquals(queryRunner.getCoordinator().getFullQueryInfo(queryId).getOutputStage().get().getState(), FLUSHING));
+
+        // wait for the sub stages to go to cancelled state
+        assertEventually(
+                new Duration(10, SECONDS),
+                () -> assertEquals(queryRunner.getCoordinator().getFullQueryInfo(queryId).getOutputStage().get().getSubStages().get(0).getState(), CANCELED));
+
+        QueryInfo queryInfo = queryRunner.getCoordinator().getFullQueryInfo(queryId);
+        assertEquals(queryInfo.getState(), RUNNING);
+        assertEquals(queryInfo.getOutputStage().get().getState(), FLUSHING);
+        assertEquals(queryInfo.getOutputStage().get().getSubStages().size(), 1);
+        assertEquals(queryInfo.getOutputStage().get().getSubStages().get(0).getState(), CANCELED);
+    }
+
+    @AfterClass(alwaysRun = true)
+    public void tearDown()
+    {
+        if (queryRunner != null) {
+            queryRunner.close();
+        }
+    }
+}